Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
55 Cards in this Set
- Front
- Back
|
Chemistry
|
science of stuff
|
|
|
chemical rxn
|
any process that turns one substance into another
substance A---substance B |
|
|
matter
|
composed of many types of atoms
|
|
|
scientific method
|
observation, hypothesis, experiment
|
|
|
theory
|
tested hypothesis that tells why things happen
serves to explain |
|
|
natural law
|
summary of observed behavior
|
|
|
law of conservation of mass
|
total mass of materials is not affected by a chemical change in those materials
|
|
|
measurement
|
quantitative observation, number and scale
|
|
|
mass
|
measure of resistance of an oject to change its state of motion
force necessary to give object acceleration |
|
|
weight
|
response of mass to gravity
|
|
|
1 liter
1 cm^3 L---cm----ml |
(1 dm)^3
1 mL 1000cm= 1000mL |
|
|
law of conservation of mass
|
(lavoisier)
mass is neither created nor destroyed |
|
|
law of definite proportions
|
(proust)
a given compund contains the same proportion of elements by mass CuCO3 --5.3:4:1 ratio of Cu, O2, and C |
|
|
law of multiple proportions
|
when 2 elements form a series of compounds the ratio of the masses of the 2nd element to 1 gram of the 1st can always be reduced to whole #'s
|
|
|
electrons
|
discovered by J.J. Thompson with a cathode ray
mass: 9.11 10^-31 kg |
|
|
Berzelius
|
said to respresent elements based on alphabetical name
Carbon-C, Calcium-Ca, Iron (ferrum)-Fe |
|
|
scientific law
|
generalization form observations
|
|
|
E=mc^2
|
energy= (associated mass change) x (speed of light)^2
|
|
|
Atom
|
"no cut"
1. smallest entities in a bulk sample that have chem. properties of the sample 2. atoms are identical, in element 3. atoms of different elements differ 4. atoms aren't created or destroyed in chem rxn and their mass doesn't change 5.compounds= joining atoms of the element of which they are composed |
|
|
law of constant composition
|
doesn't matter how, when, where substance is prepared, won't effect elemental composition
|
|
|
mercury
|
as discovered by Torricelli
mercury is both a barometer (measures pressure) and an altimeter (measures height, as the levels of mercury change according to height |
|
|
atmospheric pressure
|
mass of air being pulled toward the center of the earth by gravity--weight of the air
|
|
|
unit conversion of pressure
atm, mmHg, torr, pa |
1 atm= 760 mmHG= 760 torr = 101, 325 Pa
|
|
|
Ideal gas law
|
PV= nRT
|
|
|
Boyle's law
|
P1V1=P2V2
V is proportional to 1/p |
|
|
Charles's law
|
V1/T1=V2/T2
v is directly proportional to T |
|
|
Avogadro's law
|
V1/n1=V2/n2
v is proportional to n at constant temp ad pressure |
|
|
STP
|
standard temperature ad pressure
0C and 1 atm |
|
|
molar mass
|
g/mol
=dRT/P |
|
|
mol
|
m/molar mass
|
|
|
Dalton's Law of partial pressures
|
Ptotal= P1 +P2 +P3
= ntotal (RT/V) |
|
|
mole fraction
|
X1= (n1/ntotal) = (P1/Ptotal)
|
|
|
effusion
|
passage of gas through a tiny hole in an evacuated chamber
|
|
|
diffusion
|
mixing of gases
|
|
|
real gas behavior
|
behave ideally at high temp and low pressure
must consider particle interactions and volumes |
|
|
moles
|
things to remember:
1 mole= atomic mass of element ex. 1 mole of Carbon= 12.01 g 6.022 X10^23 atoms= 1 mole |
|
|
getting molar mass
|
ex. molar mass of CH4
1 x 12.01 g C 4 x 1.008 g H ____________ 16.04 g = 1 mole of CH4 |
|
|
Kinetic theory of gases
|
1. atoms and molecules obey Newton's law of motion
2. gas molecules don't exert forces on each other 3. gas molecules interact w/ container walls only when they hit them 4. collisions are elastic 5. ignore shape and size of gas molecules 6. motion is random |
|
|
Newton's Law of motion
|
1.An object in motion stays in motion (and continues in straight line unless acted on by force), and object at rest stays at rest
2. change in motion, caused by force, happens i the same direction the force is acting and is inversely proportional to the mass of the object 3. every action has an equal and opposite reaction |
|
|
momentum
|
mass x acceleration
|
|
|
KE=
|
2/3 RT
|
|
|
temperature
|
number that scales the KE of motions of molecules in a sample of matter (measuring energy)
|
|
|
energy
|
number you can attribute to physical system that tells you how much work needs to be done in the future
|
|
|
heat capacity
|
amount of energy needed to be put in a system to make substance's temperature rise 1K
|
|
|
mass percent
|
mass of each element in 1 mole of compound compared to total mass of 1 mole of compund
1. obtain molar mass of compound and indiv. elements 2. MM ratio of element versus compound x 100% |
|
|
empirical formula
|
percent to mass
mass to mole divide by small multiply by whole |
|
|
molecular formula (using EF)
|
1.take molar mass of EF
2.divide molecule weight of compound by molar mass of EF 3.multiply resulting whole number to EF |
|
|
molecular formula
|
1. percent to mass
2. mass X molar mass of compound 3. molar mass of element and compound to mol |
|
|
significant figures
|
1. non-zero digits always
2. any zeros between 2 sig. figs 3. a final zero or trailing zeros in the decimal point |
|
|
rounding off
|
1. #<4 ---- drop it
2. #>5 -----increase proceeding # by 1 3. #=5-----make proceeding # even (zero is even) |
|
|
electrolysis
|
coined by Faraday
separating chemically bonded elements and compounds by running electric current through them |
|
|
stoichiometry
|
1. balance equation
2. mass to moles 3. moles of known to unknown substance using mole ratio 4. convert from moles back to grams if necessary |
|
|
limiting reactants
|
1. convert g-->mol (to make sure the moles are in terms of the rest of the substances)
---OR-- 2. mol ratio ( compare moles in equation to moles they give you) |
|
|
percent yield
|
actual yield
_____________ theoretical yield X100% |
|
|
theoretical yield
|
amount product formed when limiting reactant is completely consumed
|
