Chemistry GRE Study – Flashcards
298 test answers
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| parent nucleus |
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| nucleus prior to nuclear decay |
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| daughter nucleus |
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| nucleus formed as result of nuclear decay |
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| alpha decay |
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| daughter has mass number 4 less than parent, atomic number 2 less than parent |
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| beta decay |
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| daughter will always be a different element but will have the same mass number as parent |
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| gamma decay |
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| daughter is identical to parent, except it has less energy |
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| first-order decay |
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| probability that a nucleus will decay in a given time is constant and independent of the surrounding of the nucleus |
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| nuclear fission |
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| when an accelerated particle such as a process when a neutron strikes a target nuclei, the nucleus can split into two or more fragments |
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| nuclear fusion |
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| pricess when an accelerated particle is captured by a target nucleus to produce a larger nucleus |
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| radius of a nucleus |
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| (1.33?10^(-13) )??A cm |
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| Bohr atom |
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| an atom with only one electron |
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| energy shells |
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| certain distances away from the nucleus |
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| number of electrons |
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| 2n^2 |
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| ground state |
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| configuration in which the electrons are in the lowest available energy levels |
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| excited state |
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| configuration in which the electron is not in the lowest available energy level |
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| valence electrons |
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| electrons with the largest value of n |
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| principle quantum number |
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| n, energy level, ?1 |
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| secondary quantum number |
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| l, angular momentum, 0-n |
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| degenerate |
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| quantum states or configurations that have identical energies |
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| magnetic quantum number |
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| m_l, -l to +l including 0 |
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| s |
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| 1 orbital |
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| p |
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| 3 orbitals |
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| d |
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| 5 orbitals |
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| f |
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| 7 orbitals |
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| spin quantum number |
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| m_s, +1/2 and -1/2 |
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| Pauli exclusion principle |
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| no two electrons in the same atom may ever have completely identical quantum numbers (n, l, m_l, m_s) |
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| Aufbau principle |
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| to find the correct ground-state electron configuration of an atom, always completely fill all lower-energy orbitals before filling any higher-energy orbitals |
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| Hund's rule |
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| when partially filling degenerate orbitals of p, d, and f subshells, always put one electron in each orbital before pairing them up. Also orient unpaired electrons so that their magnetic spins are all aligned in the same direction |
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| atomic size trend |
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| increases as one moves down or the left in the periodic table |
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| atomic and ionic radii |
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| cation < neutral atom < anion |
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| isoelectronic species |
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| two atoms or ions that have the same number of electrons |
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| ionization |
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| removal of an electron from a neutral atom |
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| endergonic process |
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| requires input of energy |
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| first ionization energy |
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| energy that is required to remove a single electron from an isolated gas-phase atom |
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| second ionization energy |
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| energy required to remove a second electron from a gas-phase atom |
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| ionization energy |
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| increases as one moves up or to the right of the periodic table |
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| electron affinity |
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| amount of energy involved in adding a single electron to an isolated gas-phase atom, more negative as you move across a row or up a column |
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| exergonic |
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| liberates energy |
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| electronegativity |
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| ability of an atom in a molecule to polarize bonding electrons toward itself, increases as one moves up or to the right within the periodic table |
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| acidity |
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| increases as one moves down or to the right in the periodic table |
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| basicity |
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| increases as one moves up or to the left in the periodic table |
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| octet |
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| the eight-electron arrangement in the outer electron shell of the noble-gas atoms |
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| cations |
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| positively charged ion |
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| anions |
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| negatively charged ion |
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| metalloid elements |
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| elements that lie right along the delineation staircase line between metals and non metals |
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| Valence Shell Electron Pair Repulsion (VSEPR) |
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| electron pairs, whether bonding or nonbonding, attempt to move as far apart as possible |
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| nonpolar bond |
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| covalent bonds that are fatter at one end than at the other |
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| malleability |
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| ability to be hammered into shapes |
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| ductility |
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| ability to be drawn into sheets and wires |
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| band theory |
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| metal is thought of as a giant molecule in which delocalized molecular orbitals cover the entire structure |
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| insulator |
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| solid in which electrons saturate a band and a considerable gap exists between the completely filled band and the next available one |
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| semiconductor |
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| has electrical properties that are intermediate between those of metals and insulators; electrical conductivity increases with incresing temperature |
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| intrinsic semiconductor |
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| solid in which the band gap is so small that some electrons from the valence band will occupy energy levels in the conduction band |
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| extrinsic semiconductor |
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| a substance that is normally an insulator can become semiconducting if small amount of other atoms are introduced intot the lattice, rendering it impure |
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| doping |
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| introduction of an impurity |
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| n-type conductivity |
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| charge carriers are negative electrons |
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| p-type conductivity |
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| charge carriers are positive holes |
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| p-n junction |
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| consists of a p-type semiconductor that's in close contact with an n-type semiconductor |
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| inversely polarized |
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| if the p-zone is connected to the negative pole of a battery and the n-zone to the positive pole, the electrons are attracted to the (+) pole and the holes to the (-) pole, which is opposite to the normal direction of the displacement of electrons and holes at the juntion |
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| directly polarized |
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| if the p-zone is connected to the positive pole, and the n-zone to the negative pole of the battery, the flow of electrons takes place in the normal direction at the junction |
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| coordinate covalent bonds |
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| covalent bond that is formed between a transition metal ion and a polar molecule, formed by the donation of a pair of electrons from a polar molecule |
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| coordination complex |
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| a molecule that consists of a transition metal ion bonded to polar molecules via coordinate covalent bonds |
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| Lewis base |
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| a molecule that donates a pair of electrons to form a covalent bond |
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| Lewis acid |
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| a molecule that accepts a pair of electrons to form a covalent bond |
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| intermolecular forces |
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| forces that exists between two or more molecules |
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| intramolecular forces |
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| forces that hold atoms together to form a molecule |
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| Coulomb's law |
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| F=k (Q_1?Q_2)/R^2 F= force of electrostatic interaction, k= Coulomb's constant= 9.0??10?^9 (Nm^2)/C^2 , Q_1=charge of particle #1 (in coulombs), Q_2= charge of particle #2, R= distance between the charges (m); if +, charges repel if - charges attract |
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| electron cloud repulsion |
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| prevents atoms from passing right through one another, steric hindrance |
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| ionic bond |
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| electrostatic attraction between two ions |
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| polar molecules |
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| have a dipole moment, and an asymmetric distribution of electron density |
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| dipole forces |
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| interactions between the charged portions of polar molecules |
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| hydrogen bond |
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| a strong dipole-dipole interaction involving a H atom covalently bonded to a F, O,or N atom that is attracted to the partial negative charge of another F, O, or N atom |
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| London dispersion forces |
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| arise from a momentary non-homogeneous distribution of electrons in an atom |
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| instantaneous dipole |
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| when an atom has a slightly positive side and a slightly negative side |
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| dispersion force |
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| the attraction between two adjacent, instantaneous, oppositely charged dipoles |
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| covalent compound |
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| when the electronegativities of a compound's constituent elements differ by no more than about 1.5 units |
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| ionic compound |
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| when the electronegativities of a compound's constituent elements differ by more than about 1.5 units |
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| crystal lattice |
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| ions in an ionic compound are arranged in regular pattern |
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| unit cell |
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| smallest unit that repeats itself indefinitely in three dimensions |
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| crystallorgraphy |
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| branch of chemistry that studies the structure of unit cells |
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| cubic |
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| cell edges: a=b=c, cell angles: ?=?=?=90° |
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| tetragonal |
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| cell edges: a=b?c, cell angles: ?=?=?=90° |
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| hexagonal |
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| cell edges: a=b=c?d, cell angles: ?=?=?=120°, edge d is perpendicular to the plane described by edges a, b, and c |
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| rhombohedral |
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| cell edges: a=b=c, cell angles: ?=?=??90° |
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| orthorhombic |
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| cell edges: a?b?c, cell angles: ?=?=?=90° |
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| monclinic |
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| cell edges: a?b?c, cell angles: ?=?=90° ??90° |
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| triclinic |
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| cell edges: a?b?c, cell angles: ????? |
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| ionic solids |
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| made of + and - ions arranged in regular arrays; each ion is surrounded by ions of the opposite charge; hard, brittle, and have high melting and boiling points, poor conductors of electricity and heat |
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| covalent solids |
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| made of atoms that are held together by very strong covalent bonds; very hard and have high melting points |
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| molecular solids |
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| made of neutral molecules, held together by dipole forces or London dispersion forces; soft and are poor conductors of electricity and heat |
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| metallic solids |
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| made of one closely packed metal element; very good electricity and heat conductors, can be soft or hard and have variable melting points |
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| close-packed structures |
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| substance where atoms pack together as closely as possible |
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| tetrahedral hole |
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| four spheres (3 in first layer, in triangular formation, and 1 above) create a regular tetrahedron about a void |
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| octahedral hole |
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| hole bound by 6 spheres (3 in the first layer, in triangular formation, and 3 in the second layer, above, also in triangular formation, but offset by 60° with respect to the 3 spheres in the first row) |
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| triangular hole |
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| hole between three adjacent speheres in the same layer |
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| coordination number (CN) |
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| number of an atom's or ion's closest neighbors within the lattice |
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| cohesive energy |
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| difference in energy between free ions and ionic solid |
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| lattice energy |
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| sum of the energies of interaction of the ions in a crystal |
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| Madelung constant |
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| the coulombic interaction can be evaluated theoretically using compressibility data, represents the effect on the ion of its neighboring ions |
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| Born-Haber cycle |
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| calculation of the total energy of a crystal determined by considering all of its formation steps and including a lattice energy contribution |
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| K_eq |
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| generic equilibrium constant |
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| dynamic equilibrium |
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| individual molecules continue to react; however, there is no net change in the amount of reactants and products |
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| K_p |
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| gaseous equilibrium constant |
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| K_a |
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| acid equilibrium constant |
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| K_b |
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| base equilibrium constant |
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| K_sp |
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| dissolution equilibrium constant of ionic solutions |
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| Le Chatelier's Principle |
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| chemical systems in dynamic equilibrium will remain in equilibrium indefinitely until acted upon by an outside influence |
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| reaction quotient (Q) |
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| value that is obtained if nonequilibrium numbers are plugged into an equilibrium expression |
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| autoionization |
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| spontaneous dissociation of water, reversible |
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| K_w |
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| dissociation constant for water, 10^-14 M^2 at 25 C |
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| Arrhenius |
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| acids produce H+ (aq); bases produce OH- (aq) |
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| Lowry-Bronsted |
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| acids are proton donors; bases are proton acceptors |
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| amphoteric molecule/ion |
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| can either donate or accept H+ (aq) in response to whatever else is in solution |
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| strong acid/base |
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| completely dissociated acid/base |
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| strong acids |
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| HCl, HBr, HI, HNO_3, H_2SO_4, HClO_4 |
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| strong bases |
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| group I hydroxides |
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| weak acid/base |
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| acids/bases that partially, reversibly dissociate |
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| quadratic equation |
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| (-b±?(b^2-4ac)?^(1/2))/2a |
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| conjugate pair |
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| made up of two molecules that have identical molecular formulas, except that one of them has an additional H+, pk_a+pk_b=14 @ 25C |
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| conjugate rules |
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| 1. the conjugate acid of a strong base is neutral 2. the conjugate base of a strong acid is neutral 3. the conjugate acid of a weak base is an acid 4. the conjugate base of weak acid is a base |
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| buffers |
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| minimize a change in pH when additional acid or base is introduced into solution, must consist of a conjugate pair of a weak acid and weak base |
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| Henderson-Hasselbalch equation |
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| pH=pK_a+log??[A^- ]/[HA] ? |
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| acid-base titration |
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| used to determine: 1. the concentraion of an acid or base 2. whether an unknown acid or base is strong or weak 3. the pK_a of an unknown acid, or pK_b of unknown base |
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| titrant |
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| known strong acid or base that is added to an unknown acid or base solution |
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| equivalence point |
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| inflection or end point, point during a titration where just enough titrant (in moles) has been added to completely neutralize the subject acid or base |
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| half-equivalence point |
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| the point at which enough titrant has been added to neutralize exactly one-half of the original unknown acid or base, point at which equal amounts of the unknown acid or base and its conjugate exist in the solution |
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| acid-base iindicator |
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| the conjugate pair of a weak acid or base where each conjugate is a different color, change color at a pH+/-1 of their pK_a |
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| alkali metals |
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| Group I, highly reducing, soft and silvery white, crystallize in the body-centered cubic crystal structure, salts soluble in water |
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| alkaline-earth metals |
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| Group II, metallic in appearance, crystallize in close-packed, hexagonal close-packed structure, hexagonal and face-centered, face-centered and body-centered structure |
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| Group III |
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| oxidation state +3 |
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| Group IV |
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| oxidation state +4 |
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| Boron |
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| forms simple trihalides, which are Lewis acids, undergo nucleophilic displacement reaction |
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| closoboranes |
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| [B_nH_n]^- |
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| nidoboranes |
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| B_nH_n+4 |
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| arachnoboranes |
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| B_nH_n+6 |
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| saline carbides |
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| largely ionic solids, formed by the elements of Groups I and II and by aluminum |
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| metallic carbides |
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| formed by d and f block elements, electric conductors |
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| metalloid carbides |
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| formed by boron and silicon and are covalent solids |
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| silicates |
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| compounds that contain metals and the tetrahedral SiO_4^2- structure |
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| aluminosilicates |
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| similar to silicates except that aluminum atoms replace some of the silicon atoms |
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| allotrope |
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| different elemental forms |
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| halogens |
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| Group VII, because of high reactivity, are only found as halides in nature, all nonmetals and diatomic |
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| rare gases |
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| least reactive nonmetals |
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| interhalogens |
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| compounds containing a halogen-halogen bond |
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| transition metals |
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| elements found between Group II and III, recovered as ores or salts, have different oxidation states due to electrons being able to be lost from two different valence shells |
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| lanthanides |
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| rare metals, oxidation state generally +3, properties are the result of partially filled f subshells |
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| actinides |
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| radioactive elements |
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| ligands |
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| coordination complexes formed with good Lewis bases |
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| monodentate |
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| ligands that form a single coordination covalent bond |
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| chelates |
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| ligands that form more than one bond |
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| molecular point groups |
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| describe the geometry/symmetry of coordination complexes |
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| crystals field theory |
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| model explaining how the presence of ligands can affect the electron configuration of a the metal atom |
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| 18 electron rule |
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| a way of gauging the relative stability of a complex 1. assign to the metal its number of valence s and outermost d electrons 2. for the ligands, assign electrons as per the following: Ligand Electrons donated to M H, CH3, CH2CH3, CN, OH, CI, NO 1 PR3, NH2, NH3, CO, RCN, ROOR’ 2 Cyclopentadinyl, indenyl 5 Benzene 6 Cyclooctatetraene 8 3.add up both contributions 4.when the organometallic complex has a charge, consider a + charge a - charge as an excess of electrons and add the corresponding number to the total complexes that have 18 electrons counted tend to be more stable than ones that don't |
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| identity (E) |
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| rotation about 360 degrees and yield the same, indistinguishable configuration |
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| center of symmetry (i) |
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| a line that divides a molecule into two identical parts,such that every atom through i meets equivalent atoms at a distance equidistant from i |
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| rotation axis (C_n) |
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| rotation about 360 degrees/n yields the same configuration |
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| mirror plane (?) |
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| reflection through a mirror plane yields the same configuration. |
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| rotation-reflection axis (S_n) |
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| some molecules exist such that rotation about an axis, followed by a reflection through a plane perpendicular to the axis, yields the same configuration |
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| symmetry operations |
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| when reflections are applied to a molecule and result in a representation that's indistinguishable from the starting configuration |
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| molecular point group |
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| the group of all possible symmetry operations that can be performed on molecules of a given configuration |
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| Pt. Group: C_1 |
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| Element: E |
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| Pt. Group: C_2 |
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| E, C_2 |
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| Pt. Group: C_2v |
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| E, C_2, 2? |
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| Pt. Group: D_2h |
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| E, 3C_2, 3?, i |
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| Pt. Group: D_3h |
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| E, 2C_3, 3C_2, 4?, 2S_3 |
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| Pt. Group: D_4h |
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| E, 2C_4, 5C_2, i, 2S_4, 5? |
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| Pt. Group: T_d tetrahedral |
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| E, 3C_4, 8C_3, 6?, 6S_4 |
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| Pt. Group: O_h octahedral |
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| E, 8C_3, 6C_2, 6C_4, 3C_2, i, 6S_4, 8S_6, 9? |
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| pairing energy |
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| energy required to pair up the electrons |
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| high spin |
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| when the strength of the crystal field interaction energy is less than the pairing energy |
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| low spin |
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| when the crystal field interaction energy is greater than the pairing energy |
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| spin-only effective magnetic moment (?_eff) |
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| function of the number of unpaired electrons n, v(n(n+2)) in units of Bohr magnetons |
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| Jahn-Teller effect |
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| octahedral and high-spin transition metal complexes often distort to lower symmetry to remove the electronic degeneracy |
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| formation of a complex |
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| M^(n+)+ L >ML^(n+) K_eq=([ML^(n+)])/([M^(n+) ][L]) |
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| Irving-Williams series |
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| K_eq increases from left to right Ba^2+ < Sr^2+ < Ca^2+ < Mg^2+ < Mn^2+ < Fe^2+ < Co^2+ < Ni^2+ Zn^2+ |
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| spectrochemical series |
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| provides an estimate of the ability of incoming ligands to cause the splitting of d orbitals Br^- < Cl^- < SCN^- < F^- < OH^- < oxalate < H_2O < NH_3 < pyridine < NO_2^- < CN^- < CO |
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| ligand substitution |
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| a coordinated ligand is replaced by another one |
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| redox reactions |
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| electron transfer processes in which the oxidation state of the metal changes |
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| organometallic compound |
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| a substance that contains at least one metal-carbon bond |
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| Grignard reagent |
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| Mg + CH_3Br -> CH_3MgBr |
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| transmetallation |
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| M + M'R -> MR + M', where M is a metal that is more electropositive than M' |
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| hydrometallation |
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| MH + H_2C=CH_2 -> MH_2C-CH_3, in the case of unsymmetrical alkenes, the M group attaches to the less hindered carbon atom, and the smaller H attaches to the most hinder C |
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| hapticity (?) |
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| describes organometallic compounds in the d and f groups, the number of atoms of a ligand that are attached to a metal atom |
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| toxic organometallic compounds |
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| include organomercury, organotin, organolead, organoarsenic, and organosilicon compounds |
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| biomethylation |
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| result of the reaction of methyl carbanions CH_3^- =, from naturally occurring biological agents such as cobalamin, CH_3CoB_12 + Hg^2+ -> CH_3Hg^+ + H_2OCoB_12^+ |
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| catalysis |
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| cyclic process, introduces new reaction mechanisms , which causes the catalyzed reaction to possess a lower Gibbs free energy of activation than a noncatalyzed reaction |
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| catalyst |
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| a substance that increases the rate of a chemical reaction without being consumed |
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| homogenous catalysis |
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| catalyst and reagents are present in the same phase |
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| heterogeneous catalysis |
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| catalyst catalyst is present in a phase different from that of the reactants, most are solids that are easily separated from the products of the reaction |
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| turnover frequency (N) |
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| the ration of the rate of the reaction (v) over the concentration of the catalyst([C] in homogenous catalysis) or the amount of catalyst (in heterogenous catalysis) |
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| solid-state chemistry |
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| branch of chemistry concerned with the synthesis, structure, properties, and applications of solid materials |
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| defect structure |
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| an important field of solid-state chemistry, defect of some sort greatly influence properties such as electrical conductivity, mechanical strength, corrosion, and chem reactivity |
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| point defects |
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| defect at single site |
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| extended defects |
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| defects that occur in 1, 2, or 3 dimensions |
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| intrinsic defects |
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| defects that are present for strictly thermodynamic reasons, Gibbs free energy is usually lowered by the presence of defects |
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| Schottky defect |
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| a point defect in which an ion is missing |
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| Frenkel defect |
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| a point defect in which an atom or ion has been displaced to an interstitial site in the lattice |
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| extrinsic defects |
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| defects that are not determined by thermodynamics and can be controlled by synthetic conditions and purification of the solid |
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| optical properties |
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| ex: color change |
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| nonstoichiometric compounds |
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| substances that have variable composition but constant basic structure, formula deviate from whole number ratios |
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| superconductors |
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| important class of solids that possess the ability to conduct electricity without resistance |
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| bioinorganic chemistry |
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| field of chemistry that studies the function of metals and nonmetals in biological processes |
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| cell membranes |
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| membrane barrier that separates a cells interior and exterior |
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| carriers |
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| alkali cations that carry molecules across the cell membrane |
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| calcium binding proteins |
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| act a receptors for intracellular calcium and structural intermediates for enzyme catalysis |
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| enzyme |
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| biological catalyst |
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| matalloenzyme |
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| important class of enzymes characterized by the presence of a metal ion that is an essential participant in catalyzed reactions |
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| heme proteins |
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| involved in electron transfer reactions, act as oxygen carriers, catalyze a variety of biochemical reactions |
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| heme |
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| consists of folded, linked amino acid chains; a macrocyclic porphyrin ring that contains iron as its central metal and whose chemistry is influenced by ring substituents that differ from one type of protein to another |
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| sublimation |
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| solid to gas phase |
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| ionization |
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| release of an electron |
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| dissociation |
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| diatomic to atomic |
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| electron affinity |
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| addition of an electron (-) |
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| lattice energy |
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| negative for ions coming together |
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| sublimation |
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| solid to gas phase |
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| ionization |
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| release of an electron |
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| dissociation |
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| diatomic to atomic |
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| electron affinity |
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| addition of an electron (-) |
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| lattice energy |
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| negative for ions coming together |
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| organic chemistry |
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| study of carbon, its compounds, and the reactions that they undergo |
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| international Union of Pure and Applied Chemistry (IUPAC) |
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| regulates the systematic nomenclature of all compounds |
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| saturated hydrocarbon |
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| acyclic, unbranched; univalent radicals |
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| enantiomers |
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| nonsuperimposable, chiral mirror images |
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| diastereomers |
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| stereoisomers that are not mirror images of each other |
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| S_N2 reaction |
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| number 2 indicates both the nucleophile and the substrate are involved in the transition state, so process is biomolecular bonds are broken heterolytically |
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| rate of S_N2 reaction for alkyl halides |
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| consider steric hindrance, as the number of substituents increases, the transition state becomes increasingly crowded, and the rate of reaction decreases, order of increasing rate me > 1 > 2 > 3 |
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| S_N1 mechanism for the substitution of alkyl halides |
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| rate determining step is ionization of the tertiary or secondary halide to form a carbocation |
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| S_N1 reactivity |
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| follows order of carbocation stability, order of increasing stability 3 > 2 > 1 > me |
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| E2 mechanism for substitution in alkyl halides |
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| in transition state, the attacking base and the leaving group want to be as far apart as possible (anti positioning). this determines the stereochemistry Saytzeff's rule applies: the more highly substituted alkenes are more stable than less substituted ones |
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| stability of alkenes |
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| depends on the number of substituents on the double bond; most stable is most substituted |
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| Hofmann product |
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| the less substituted alkene will predominate |
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| Diels-Alder reaction |
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| occurs between a conjugated diene and a dienophile, product always contain 1 more ring than was present in the reactants, stereospecific |
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| nucleophilic aromatic substitutions |
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| addition of a nucleophile and formation of a carbanion intermediate, followed by the loss of the halide ion electron-withdrawing ortho- and para- substituents stabilize the carbanion intermediate more than meta- substituents in the absence of electron-withdrawing substituents, this reaction is very rare and proceeds through a benzyne intermdiate |
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| Saytzeff's rule |
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| when more than one beta carbon bears hydrogen atoms, it is the most substituted carbon that undergoes elimination |
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| Friedel-Crafts reaction |
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| example of electrophilic aromatic substitution, in first step a carbocation is generated by reaction of the alkyl halide with aluminum trichloride, the second step is electrophilic attack on benzene to form alkylbenzene |
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| carbocation |
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| a positive ion in which a positive charge resides on a carbon atom |
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| carbanion |
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| formed after heteroltic cleavage of a bond between a carbon and a less electrnegative atom, resulting carbon has one additional electron, and it is therefore negatively charged |
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| free radical |
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| generated by the absorption of light and subsequent homogenous bond dissociation lack an octet of electrons and are exremely reactive as well as electrophilic |
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| carbene intermediate |
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| neutral molecules of general formula R_2C: in which a carbon atom has two sigma bonds and two electrons |
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| stability of free radicals |
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| methyl < primary < secondary < tertiary |
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| propagation step |
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| in the presence of an alkane, the radical formed will break one of the C-H bonds, one electron remains on the alkane which becomes an alkyl radical and the other electron forms the bond inteh newly formed H-X molecule the alkyl radical reacts with a halogen molecule to form the halogenated alkane |
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| Grignard reagent |
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| RX + Mg -> RMgX |
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| synthesis f alkanes |
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| 1. reduction of alkyl halides 2.catalyzed hydrogenation of alkenes and alkynes to produce alkanes 3. Corey-House synthesis |
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| Corey-House synthesis |
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| (a) 2R-Li +CuI -> (under dry ether) R_2CuLi +Li (b) R_2CuLi + R'-X -> R'-R + RCu +LiX |
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| Major reaction of alkanes |
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| 1. thermal dehydrogenation (cracking) 2.combustion 3. halogenation |
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| polymerization |
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| produces polymers which are large molecules made of chain-linked starting molecules called monomers or mers |
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| synthesis of alkenes |
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| 1. dehydrogenation of alkanes 2. dehydration of alcohols (ROH 3. dehyrohalogenation of alyl halides (RX) 4. dehalogenation of vicinal dihalides 5. reduction of alkynes (RC-Cr) |
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| reactions of alkenes |
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| 1. addition of hydrogen halides (HX) across double bonds (Markovnikov addition) 2. hydration of alkenes to produce alcohols (Markovnikov addition) 3. addition of H_2SO_4 to alkenes to produce alcohols (Markovnikov addition) 4. oxymercuration-demercuration of alkenes to produce alcohols 5. catalytic hydrogenation of alkene to produce alkanes 6. cyclopropanation 7. allylic substitution 8. ozonolysis of alkenes to produce carbonyl groups |
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| Markovnikov's rule |
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| addition of a proton to the double bond of an alkene yields a product in which the proton is bonded to the carbon atom that already bears the greater number of hydrogens |
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| preparation of alkynes |
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| 1. dehyrohalogenation of dihalides 2. alkyl substitution |
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| vic-dihalides |
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| halogens on adjacent carbons |
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| gem-dihalide |
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| halogen atoms are bound to the same carbon |
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| diene |
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| alkene that has two C=C bonds in the formula |
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| conjugated |
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| double bonds that are separated by only one single bond, more stable than isolated bonds |
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| isolated |
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| double bonds that are separated by more than one single bond |
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| synthesis of dienes |
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| 1. dehydration of diols 2. dehydrogenation of alkenes 3. dehydrohalogenation of dihalides |
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| reactions of dienes |
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| 1. addition of hydrogen 2. Diels-Alder reaction |
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| use of grignard reagents |
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| 1. formaldehyde to primary alcohol 2. aldehyde to secondary alcohol 3. ketone to tertiary alcohol 4. nitrile to ketone 5. carbon dioxide to carboxylic acid |
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| primary alcohol |
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| -OH group bound to a carbon that's directly bound to only one other carbon |
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| secondary alcohol |
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| -OH group bound to a carbon that's directly bonded to only two other C atoms |
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| tertiary alcohol |
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| -OH group bound to a carbon that's directly bonded to three other C atoms |
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| alkoxide ion |
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| RO- produced when a proton of alcohol is removed by a strong base |
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| reactions of alcohols |
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| 1. oxidation of primary alcohols to carboxylic acids 2. oxidation of primary alcohols to aldehyde 3. oxidation of secondary alcohols to ketones 4. reduction of alcohols to alkanes 5. synthesis of alkyl halides 6. dehydration to alkenes 7. dehydration to ethers 8. tosylation 9. acylation 10. deprotonation to alkoxide |
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| thiols |
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| -SH (sulfhydryl) functional group bound to a carbon |
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| synthesis of esters |
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| 1. Williamson synthesis 2. intermolecular dehydration |
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| benzyne |
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| compounds that are forded as reactive intermediates in the reaction of alkyl halides with strong bases |
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| enols |
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| compounds that exist as an equilibrium mixture of ketone and alcohol tautomers |
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| organometallic compound |
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| consists of a carbon atom covalently bonded to a metal |
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| carbohydrates |
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| C_n(H_2O)_m, synthesized by almost all living organisms as a source of metabolic energy |
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| monosaccharides |
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| saccharides that cannot be hydrolyzed to simpler structures |
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| disaccharide |
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| can be hydrolyzed to yield two monosaccharides |
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| aldoses |
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| contain the aldehyde functional group |
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| ketoses |
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| contain the ketone group |
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| epimer |
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| compounds whose stereochemistry differs at only one carbon |
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| polysaccharides |
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| consist of several monosaccharides linked by glycosidic bonds |
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| oligosaccharides |
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| contain up to ten monosaccharides |
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| ribonucleosides |
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| building blocks of nucleic acids glycosides of ribofuranose |
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| isoelectric point |
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| the pH at which the amino acid exists as an equilibrium mixture of anionic and cationic forms |
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| dalton |
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| unit of mass equal to the mass of one hydrogen atom |
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| simple proteins |
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| polypeptide assemblies that hydrolyze to their constituent amino acid residues |
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| conjugated proteins |
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| incorporate groups such as carbohydrates, lipids, nucleic acids, and various prosthetic groups |
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| prosthetic group |
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| active groups often the site of the main biochemical activity of the protein |
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| primary structure of proteins |
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| covalent assembly amino acid sequence and the presence of disulfide bridges |
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| secondary structure of proteins |
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| arragnements adopted by the amino acid sequence alpha-helix, beta-pleted sheet, random coil can coexists in the same protein |
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| alpha-helix |
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| a polypedtide arrangement in which the carbonyl groups on one turn of the helix hydrogen bond to the hydrogens of the peptide N-H bond of the next turn |
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| beta-pleated sheet |
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| a polypeptide arrangement in which the chains line up side by side with the carbonyl groups of one chain hydrogen bonded to the hydrogens of the N-H bond of the adjacent chain |
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| random coil |
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| any nonhelical or nonpleated sheet polypeptide arrangement |
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| tertiary structure of proteins |
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| the complete three-dimensional conformation of the protein and the folding pattern of its secondary structure |
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| quaternary structure of proteins |
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| the "sum total" of the protein assembly, including complexations with ligands, inhibitors, etc |
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| physical chemistry |
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| the study of changes is the study of changes in energy and entropy and the rate of change of nonequilibrated systems |
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| thermodynamics |
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| study of transformations of various kinds of energies and the exchange of energy between systems and their surroundings |
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| system |
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| any part of the universe, any object, and any quality of matter |
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| state properties |
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| measurable variables |
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| surroundings |
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| includes everything around the system |
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| boundary |
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| encloses a system, setting it apart from its surroundings imaginary construct which serves either to (a) completely isolate the system from its surroundings or (b) allow interactions between the system and its surroundings |
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