Descriptive Inorganic Chemistry Final – Flashcards
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Finding Bond Order
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1/2(# of e- in bonding orbitals- 3 e- in antibonding orbitals)
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diamagnetic
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all spins are paired, weakly repelled by magnetic field
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paramagnetic
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one or more e- unpaired to give total spin of >0, attracted to magnetic field
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ferromagnetic
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spins align with those in neighboring regions leading to larger regions with very high spin. All of the domains align with an external magnetic field. These are strongly attracted to a magnetic field
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antiferromagnetic
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spins align opposite of neighbors, bulk material w/ little or no spin, weakly attracted to magnetic field
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ferrimagnetic
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number of opposing spins is not balanced, spins do not completely cancel each other out. weakly attracted to magnetic field
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principle quantum number
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n, size and energy of oribital, layer, 1-infinit
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angular momentum quantum number
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l, shape of orbital, 0 - n-1, spdf (0123)
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magnetic quantum number
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ml, orientation of orbital in space, -l - +l (including 0)
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spin quantum number
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ms, allows for 2 e- in an orbital, +1/2, -1/2
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the point where a ferromagnetic material begins to act like a paramagnetic material
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Curie point
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What are two requirements that species must meet in order to form solid solutions with one another
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Similar packing structures and radius sizes
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finding radius of atom with primitive cubic unit cell given the density
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convert molar mass to mass per atom, convert to mass per unit cell, use density to calculate volume of cell, take cube root to get the cell edge, divide by 2 to get r, convert to pm
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_____ defines which element it is
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protons
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What makes a pi orbital different from a sigma orbital
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sigma- electron density and orbitals lie along the bonding axis, pi- electron density is above and below each atom
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what is ionization energy
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the amount of energy required to remove an electron from an atom in the gas phase
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how does IE vary across the periodic table?
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IE increases from left to right and decreases from top to bottom
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what unit cell structure results from cubic close-packing
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face-centered unit cell, 2r x (squareroot)2 for cell edge
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What is a spherical node
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the spherical area around a nucleus where no electrons appear
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which elements exist as gases at SATP
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H, N, O, F, Cl, noble gases
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why does Zinc only adopt one charge (2+)
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it loses its valence e- first (the 4s e-). It doesn't lose any d-orbital e- because it has a full set of d-orbitals, which is a stable configuration
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When the average electronegativity is high and the difference in electronegativity is low, ________ bonding results
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covalent
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When the difference in electronegativity is very low and the average electronegativity is low, ________ bonding results
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metallic
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When the difference in electronegativity is very high and the average electronegativity is intermediate, ________ bonding results
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ionic
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.uniqueness principle
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the chemistry of the second period elements is often quite different from other elements in their group
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inert pair effect
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when the e- are more difficult to remove than expected, leading to a charge 2 less than expected for an ion. In+ instead of In3+
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How do Latimer diagrams work
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if the reduction potential for a species is more positive than that for the previous step, the species in the middle is unstable. It will dispropotionate to make the two species on either side of it in the diagram
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DH, DS, DGhigh, DGlow
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-+-- +-++ ++-+ --+-
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define lattice energy
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The energy change upon formation of 1 mole of an ionic solid from its constituent ions in the gas phase
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As you move down a group, the melting and boiling points of metals generally ______ and their reactivity ________.
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derease, increase
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Why are cations smaller than their neutral counterparts
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They are losing electrons but increasing in effective nuclear charge, so their electron cloud is drawn in tighter
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why does graphite not spontaneously burst into flame at room temperature if the Gibbs free energy for its reaction with oxygen is -390kJ/mol
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activation energy for combustion of graphite is very high, so the reaction will take a great deal of time to occur
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oxyacids with (more/less) oxygen are more acidic due to extra electronegativity pulling e- away from H, making it easier to be pulled off
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more
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What are the three types of holes in an ionic lattice and what are the coordination numbers of ions resulting in each of the types of holes?
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cubic -8, octahedral - 6, tetrahedral - 4
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two "real world" uses of CaCl2
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drying agent, salting sidewalks, keep dust down
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dissolution of a salt can often lead to a decrease in the entropy of the system, why?
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When this happens, the water will form hydrate rings around the ions, the more orderly formation leads to a lower entropy.
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what is the most corrosive material known
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LIQUID Lithium
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two industrial methods used for the preparation of H2
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Catalytic Hydrocarbon-steam reforming, Carbon-Steam reaction C3H8(g) + 3 H2O(g) =(Ni, change) 3CO(g) + 7H2(g) C(s,coal) + H2O(g) =(change, Fe or Ru) CO(g) + H2(g)
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What is a metallic hydride
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type of compound produced when a hydrideand d-block or f-block atom combine. The hydrogen in the formula is often not a whole number.
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Downs Process
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a central graphite anode and a cylindrical steel cathode. Cl2 bubbles out at the graphite anode, and the low density Na metal, which would normally float to the top of the cell and react with the liberated Cl2, is kept seperate and pumped out through a different pathway. Used to isolate sodium from NaCl and Mg from MgCl2
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Why did Radium become too expensive for Marie Curie to buy herself?
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The new element became so popular in revigorators and watches that its value sky rocketed and became much more expensive
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What type of compounds are the alkaline earth metals able to make with nitrogen that make them unique among the elements?
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Nitrides 3Ca(g) + N2(g) = Ca3N2(s)
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Reactions with oxygen
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4Li + O2 = 2Li2O 2Na + O2 = Na2O2 K + O2 = KO2
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What interesting property does potassium superoxide have that makes it useful for applications in submarines and space capsules
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KO2 is able to scrub out CO2 while producing O2 at the same time, the potassium carbonate fromed can then be reacted with water and more CO2 to scrub out even more CO2
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How to name crown ethers
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# of total atoms in the backbone - crown - # of O atoms in molecule
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How is tritium formed in the natural environment?
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Neutrons in cosmic rays interact with the nitrogen in the atmosphere, creating a nuclear transmutation reaction where the nitrogen becomes carbon, giving off tritium. 14/7N + 1/0n = 12/6C + 3/1H
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How is tritium prepared synthetically
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6/3Li + 1/0n = 4/2He + 3/1H
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___________ comprise the largest group of covalent hydrides
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hydrocarbons
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What is the desired end product of the Solvay process?
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Sodium Carbonate
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What is heavy water?
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Deuterium oxide, D2O
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What is one "real world" use of D?
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used as a solvent when using nmr analysis
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what are the two ways heavy water is produced?
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It can be isolated by performing electrolysis on water, because deuterium moves slower due to its higher density, which means protonium will be electrolyzed first, and the bonds of deuterium are slightly stronger, so it is harder to be seperated by electrolysis. Electrolysis can be stopped when only deuterium is left. It is isolated naturally in natural bodies of water with no inlets or outlets, such as the Dead Sea. This is because the protonium is more easily evaporated, leaving behind bodies full of deuterium.
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What is one "real world" use of BaSO4?
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Imaging agent for X-ray imaging of the digestive tract.
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Describe two consequences of the weak metallic bonding in the alkali metals (in terms of their observed properties).
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They are easy to cut with a knife, and also have relatively low melting/boiling points.
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Describe the industrial process used for the production of NaOH.
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prepared by electrolysis of brine, synthesized in a diaphragm cell in which the cathode and the anode compartents are separated by a diaphragm of teflon with pores large enough to allow the brine to pass through. Cl- is oxidized to Cl2 gas at the andoe, and water is reduced to H2 gas and OH- at the cathode. The cathode is removed, which contains about 11% NaOH and 16% NaCl. It is evaporated, and the less soluble NaCl precipitates out, leaving a solution that is 50% NaOH and 1% NaCl. Pure enough.
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Who was the scientist who postulated that particles might have wavelike properties?
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De Broglie
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Pauli Exclusion Principle
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only two electrons can be placed into any orbital
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Aufbau principle
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put electrons in order of increasing energy
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Hunds rule of maximum multiplicity
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the ground state electron configuration has the maximum number of unpaired electrons, when filling orbitals of the same energy, enter them into the orbitals singly before pairing them
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Name of group 15, group 16, and group 17
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pnictogens, chalcogens, halogens
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Which two periodic trends allow you to explain most or all of the others?
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atomic radius (increasing from right to left, top to bottom) and effective nuclear charge (increasing from left to right, bottom to top)
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What is the difference between a covalent radius and a van der Waal's radius?
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covalent radius is 1/2 the distance between the two nuclei of an atom bonded to another atom of the same species, van der waals is 1/2 the distance between the two nuclei of an independent atom pushed as close as possible to another independent atom of the same species
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what is the one truly defining property of a metal
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conductor of electricity in all 3 dimensions, with conductivity decreasing as T increases
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What is the band theory of bonding for metals?
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Metal atoms bond with molecular orbitals, and as more atoms are introduced, more molecular orbitals are introduced. The orbitals get closer and closer and closer to each other in energy until the graphs of the molecular orbitals looks like a band of filled orbitals and a bond of unfilled orbitals.
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How does the band theory account for the property of luster in metals?
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Since the orbitals are essentially continuous, they can absorb and then reemit any wavelength/energy of light, accounting for the luster of metals
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What is a catalyst and how does it function?
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A catalyst is a substance that changes the path from product to reactants, the path it changes to has a lower activation energy, so less energy and usually less time is necessary to make the reaction happen.
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What is the standard enthalpy of formation?
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The standard enthalpy of formation is the amount of energy required to form a compound from its constituent elements in their standard state under standard conditions, 298K and 1 atm
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Why is the "change of H final" for a pure element in its standard state equal to 0 kJ/mol
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An element in its standard state is in the same form it would be under standard condistions, no change occurs
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Why is AlF3's melting point so much higher than AlI3's?
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I- is much larger and more polarizable than F-. This makes AlI3 have a lot of covalent character, making it have a lower melting point.
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What is the Bronsted-Lowry concept of acids and bases?
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Acid is a proton donor, base is a proton acceptor
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What is the difference between dissociation and ionization
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dissociation is when an ionic compound serparates into its ions in a solvent. Ionization is when a covalent compound, such as an acid, separates into its ions in a solvent
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If the pKa of H3PO3 is 1.80, what is the pKa of H2PO3-?
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6.80 (add 5)
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If the pKa of H3PO3 is 1.80, what is the pKb of H2PO3-?
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12.2 (pKa+pKb=14)
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What is a stronger base, NH3 or NF3?
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NH3, F is more electronegative, drawing the electrons closer to itself and making it harder for N to bond to a proton (Bronsted-Lowry) or donate its electrons (Lewis)
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Will HgF2 + BeI2 = HgI2 + BeF2 take place?
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Hg and I are soft, and Be and F are hard, the products should be favored in reaction.
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What is an example for H being placed in the alkali metals group and an example for being placed in the halogens group?
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has a 1+ charge, forms diatomic molecules with itself
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Which elements form the ionic hydrides?
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alkali/alkali earth metals from Calcium down
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Which elements form the covalent hydrides?
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all of the nonmetals except noble gases, and also with some of the less electropositive p-block metals such as Al, Ga, Sn, and Pb
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Which elements form the metallic hydrides?
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d-block and f-block metals, usually don't have whole number ratios of the elements in the compounds
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What are the three isotopes of hydrogen?
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protium, deuterium, tritium
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What is a clathrate
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when a molecule or atom is trapped within the crystal lattice of another molecular species
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What is the importance of methane clathrates?
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Huge deposits of CH4 clathrates exist on the ocean floor in the deep ocean. Also in the permafrost in Canada and Russia. 1 mL of the clathrate contains 175 mL of methane gas. Some concern about the warming of the oceans and permafrost could result in the destabilization of the clathrates, releasing huge amounts of methane and causing rapid global warming
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What are two pieces of experimental evidence that show that the ionic hydrides do, in fact, contain the H- ion.
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1. Molten hydrides conduct electricity 2. during electrolysis H2 forms at the anode 3. xray studies shows >80.7% of e- density transferred from Li to H in LiH
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What are two uses for heavy water?
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controlling neutrons in fission reactors, and as an nmr solvent
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What is historically important about the nuclear chemistry of Be?
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When bombarded with alpha particles, it produced a neutron. When this experiment was done for the first time, no one knew neutrons existed, and it produced the first observed neutron.
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What property does Be have that makes it useful in nuclear weapons and nuclear power plants?
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It reflects rather than absorbs neutrons, allowing the process to create the neutron flux necessary for the desired reaction to occur
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Describe the Dow Chemical extraction process for the production of Mg
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Ca(OH)2 is added to sea water, and the less soluble Mg(OH)2 precipitates out. The Mg(OH)2 is then reacted with HCl to create MgCl2. MgCl2 under goes electrolysis using a Downs cell, which produces isolated magnesium, as well as HCl which can be used in the previous step to make MgCl2 from Mg(OH)2.
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What is a Grignard reagent?
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It is the compound formed when Mg metal reacts with alkyl halides in ether to generate a species in which the Mg inserts itself into the bond between C and the halide, typically Br. They are often used for reaction with carbonyl-containing organic molecules to form new C-C bonds
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Describe three ways in which the thermoluminescence of CaO has been used
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It can be used to create bright lights for lighthouses, surveryor lamps, and stage lights.
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How is CaO produced?
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CaCO3 is burned at high temperatures to release CO2, resulting in CaO.
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What does CaC2 do upon reaction with water that made it particularly useful substance in the past?
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It creates acetylene and Ca(OH)2, the acetylene could be used as a fuel for lamps, and can also be burnt in pure oxygen to create extremely hot flames used in welding
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What is the overall reaction that takes place in the Solvay process?
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2NaCl + CaCO3 = (NH3(aq)) Na2CO3 + CaCl2
