element
a pure substance made of only one kind of atom, cannot be broken down
compound
a pure substance made of 2 or more kinds of atoms, cannot be broken down
molecule
a group of atoms bonded together
homogenous mixture
a mixture in which the composition is uniform throughout, can be separated
heterogenous
a mixture in which the composition is non-uniform throughout, can be separated
decantation
less dense liquid is poured off from the more dense liquid, therefore separating the liquid and solid
filtration
solids separated from liquids by using filter paper to trap solid component
distillation
using different boiling points of substances to separate homogenous mixtures into their components
intensive property
properties that do NOT depend on the amount of matter present (ex: melting point, conductivity, color)
extensive property
properties that depend on the amount of matter present (ex: volume, mass)
physical property
property used to describe matter without changing the composition of the matter (ex: color, boiling point)
chemical property
substance's ability to change into something new (ex: rusting, cooking, combustion reactions)
solid
definite volume + shape, packed particles, held by strong attractive forces, less energy
liquid
definite volume, indefinite shape, moves faster + slightly higher energy
gas
indefinite volume + shape, weak attraction, moves fastest + high energy
plasma
particles ionize
Law of Conservation of Energy
energy is neither created nor destroyed; only converted into a different form
physical change
change in substance that does not involve a change in composition of substance/change in matter where you don't create anything new (phase changes are all physical changes, physical changes could be reversed)
chemical change
a change in which one or more substances are converted into different substances - chemical changes cannot be reversed (any reaction) - signs: bubbles, production of new odor or vapor
tera-
T, 10^12
giga-
G, 10^9
mega-
M, 10^6
kilo-
k, 10^3
hecto-
h, 10^2
deka-
da, 10^1
deci-
d, 10^-1
centi-
c, 10^-2
milli-
m, 10^-3
micro-
μ, 10^-6
nano-
n, 10^-9
pico-
p, 10^-12
C to F equation
F = 1.8C + 32
K to C equation
C = K - 273
precision
how close a group of measurements are to each other
accuracy
how close a measurement is to the true value
percent error equation
(100)(experimental value-theoretical value)/theoretical value
sig figs
go from the right for decimals, go from the left for non-decimals
John Dalton
atomic theory, discovered initial model of the atom (knew nothing about subatomic particles)
JJ Thomson
discovery of negative subatomic particles, cathode ray experiment (discovered electrons), Plum Pudding Model
Ernest Rutherford
discovered the nucleus through Gold-Foil experiment
Neils Bohr
created Bohr Model (model that organized electrons in energy clouds around the nucleus)
James Chadwick
discovered the neutron
average atomic mass=
(mass isotope 1)(relative abundance) + (mass isotope 2)(relative abundance)
you have to add the charge for ____ when writing them out
transition metals
isotope notation
atomic mass on top, atomic number on bottom, the element to the right
ion
charged atom
ionic compound
nonmetal + metal, lose/gain electrons, strong conductors, high melting + boiling points, forms crystal lattice structure
cations (metals)
positively charged ions
anions (nonmetals)
negatively charged ions
naming ionic compounds
metal anion(ide)
silver (Ag) is always ____ charge
+1
zinc (Zn) is always ____ charge
+2
hydronium
H3O+
cyanide
CN-
oxalate
C2O4 2-
nitrite
NO2-
sulfite
SO3 2-
phosphite
PO3 3-
hypochlorite
ClO-
chlorate
ClO3-
permanganate
MnO4-
chromate
CrO4 2-
dichromate
Cr2O7 2-
ammonium
NH4+
hydroxide
OH-
carbonate
CO3 2-
nitrate
NO3-
sulfate
SO4 2-
phosphate
PO4 3-
chlorite
ClO2-
perchlorate
ClO4-
acetate
C2H3O2-, CH3COO-, CH3CO2-
Avogradro's number
6.02x10^23
covalent compound
nonmetal + nonmetal, shared electrons, strong insulators, do NOT conduct electricity, low melting + boiling point)
tetra
4
penta
5
hexa
6
octa
8
nona
9
deca
10
naming covalent compounds
add prefixes to element 1 (except if it is 1), add prefixes to element 2 (even if it is 1)
percent composition
(100*mass of element)/(total mass of compound)
molecular formula (finding the "magic number)
(molar mass of the compound)/(molar mass of the empirical formula)
synthesis reaction
A+B-->AB
decomposition reaction
AB --> A + B
single replacement reaction
AB + C --> AC + B (metals only switch w/ metals)
double replacement reaction
AB + CD --> AD + CB (metals only switch w/ metals)
combustion reaction
hydrocarbon + O2 --> CO2 + H2O
diatomic elements
H2, N2, O2, F2, Cl2, Br2, I2 (7)
stoichiometry
using coefficients to convert between different types of elements
percent yield
(actual yield*100)/(theoretical yield)
limiting reactant (reagent)
the reactant that is completely consumed when a reaction is run to completion (smallest when you test the reactants on one product)
molarity equation
(moles of solute)/(liters of solution)
concentration
how much "stuff"" is in the solution
solution
homogenous mixture of 2 or more substances in a single phase (aq)
solute
the substance being dissolved (usually smaller)
solvent
the dissolving medium (usually larger)
dissociation
separation of ions in a solution for ionic compounds
ionization
separation of ions in a solution for covalent compounds
electrolytes
a substance that dissolves in water to give a solution that conducts electric current