Definitions and History of Atom from Test 1 – Flashcards
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Unlock answersMass |
A measure of amount of matter. |
Matter |
Anything having mass and volume. |
Element |
Pure substance of one type of atom. Example: diamond, O2
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Compund |
anything made of multiple elements bonded together. Ex: H2O, CO2 |
Extensive Properties(btw will be on CFA's) |
Change according to the amount of matter.; Examples: weight, mass, volume, surface area. |
Intensive Properties(on CFA's too) |
Do not rely or change as the amount of matter changes. Examples: luster, boiling point, melting point, color, taste, density. |
Physical Properties |
Something observed without changing identity. Examples: 5 states of matter(gas, liquid, solid, plasma), freezing/melting point, temperature, dissolving, shredding, cutting down a tree, solubility, density. |
Chemical Properties |
Substances ability to undergo change into a new substance. Examples: oxidizing(rusting), burning, cooking is always a chem reaction, rotting/decomposing. |
Mixtures |
blend of 2 or more kinds of matter which retains their original properties/identity.
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Homogenous |
"uniform in composition," evenly mixed a.k.a. solution. Examples: sugar water, salt water, mayo, coke, birdseed, italien dressing (only if it is physically seperated into being homogeneous!!!!) |
Heterogeneous |
"not uniform in composition." Can physically seperate to become homogeneous! Examples: salde, water and oil, italien dressing (note from homogeneous!) |
Pure Substance |
fixed composition, different from mixtures: 1. all samples have identical properties (behaves same) 2. all samples have identical compositions (same chemical makeup) note: cannot vary at all |
Units |
length-meters mass-kilograms time-seconds amount of substance-moles(n) temperature- Kelvin (K) |
Prefixes |
kilo-kg-10^3 1000g=1kg deci-dg-10^-1 10dg=1g centi-cg-10^-2 100cg=1g milli-mg-10^-3 1000mg=1g micro-ug-10^-6 100000ug=1g nano-ng10^-9 1000000000ng=1g |
Qualitative and Quantitative |
Qualitative: descriptive Quantitative: numerical |
Accuracy |
how close are we to the actual number |
Precise |
the grouping of data |
Percent Error and Percent Yield |
PE= absolute value of TY(theoretical yield) - AY(actual) over TY multiplied by 100 PY= AY over TY times 100 |
Democritus(minor) |
coined the term "atomus" meaning indivisible. Said if you cut something over and over and over at some point you cant make it any smaller. |
John Dalton (major) |
1st Atomic Theory combined of 5 postulates and 3 laws: -Law one: law of conservation of mass. Mass cannot be created or destryed. -Law two: law of definite proportions. If you break a chemical apart it will be the exact same pieces combined in the exact same way. Law three: law of multiple proportions. Having no half atoms, must have whole number ratio's. 5 postulates: 1. all matter is made of tiny particles called atoms. 2. atoms of a single element are identical in size, mass, and properties; atoms of different elements difeer in size, mass, and properties. 3. atoms cannot be subdivided or destroyed. 4. atoms of different elements combine in whole number ratios 5. chemical reactions= atoms are combined, seperated, or rearranged. ; NOTE:one of the postulates that is not considered true today is that atoms are indivisible ; He said that all atoms of a given element are alike. This is not true due to the existence of isotopes. Isotopes are atoms of the same element that have ; different masses because they have different ; numbers of neutrons. During a chemical reaction, atoms can change their identities |
JJ Thomson (support) |
uses cathode ray to discover negative parts of the atom. Plum Pudding Model |
Max Planck (minor) |
Quantum=minimum energy required that can be gained or lost by an atom. |
Einstein(minor) |
photon=a particle of electro magnetic radiation that has zero mass and a quantum of energy. |
Millikan(support) |
discovered electron mass to oil change with oil drop experiment. |
Rutherford(major) |
Gold Foil Experiment. Discovered positive nucleus. |
Bohr(support) |
modeled photon absorption and emission with Hydrogen.; |
De Broglie |
electrons have wave-particle duality; electrons are waves in a confined space around the nucleus of an atom (electrons have to be in a certain area). |
Heisenberg(major,support,minor) |
Uncertainty Principle: we can know where an electron is and how fast its going, but we can never know both. |
Schrodinger(MAJOR) |
Quantum Theory: describes mathematically the various properties of electrons. So taking Daltons atomic theory and proving it with numbers. |
Electro Magnetic Radiation |
a form of energy that exhibits wave-like behavior as it travels through space.; ex:gamma rays extremely high, but radio waves are low. Frequancy is the amount of ways in a certain time. ; |
Light equations |
C=;;; C=speed of light (3.00x10^8 m),;;=wavelength measured in nm,;;=frequency E=h;; E=energy, h= Plancks Constant (6.626x10^-34 J/s),;;=frequency ; ; ; ; ; ; |
Ground State and Excited State |
GS= normal, flat energy level; ES= high energy |
Subelevel(orbital) |
3D region around nucleus where an electron probably is found. ; |
Quantum Numbers |
specific properties of orbitals and properties of electrons is orbitals. 1. Principle Quantum #: n, 1 to infinity, main energy level 2. Angular Momentum Quantum #: l;, n-1 to zero, sublevel (s=0, p=1, d=2, f=3) s is 1 orbital, p is 3 orbitals, d is 5 orbitals, f is 7 orbitals (one orbital holds 2 electrons) 3. Magnetic Quantum #:;ml is -l to l 4. Spin Quantum: s +1/2 and -1/2 spin of an electron ; |
Quantum Numbers more |
n=row number l= block type (s=0,p=1,d=2,f=3) ml= column in block (ex -1, 0, 1 for if l=p) (-l or l) s=spin (-1/2 if arrow is down, +1/2 if arrow is up) |
Mole |
the amount of particles required to have 12g of Carbon-12 ; |
Avogadro's Number |
6.02x10^23 parts over 1 mol parts can equal atoms, molecules,or some other tiny particle. |
Molar Mass |
the mass of one mole of a pure substance MM=g/mol periodic table measured in g/mol |