Question | Answer |
Calculate Oxidation # of an element | Molecule charge = (# of O)(oxygen's oxidation #: -2)+element in questionEX: SO3^2- calculate oxidation # of S-2=3(-2)+S; -2=-6+S; add 6 to both side to cancel; S=4 |
LEO the lion says GER | loose electrons oxidize; gain electrons reduce |
Base | Proton acceptor |
Acid | Proton donor |
Reactions in solutions | Write equation from species present; balance equation; determine moles of reactants; identify limiting reactant; determine moles of products |
To determine molarity of a compound | M=moles of solute/L of solution |
To determine molality | Molal=moles of solute/mass of solvent(kg) |
To determine % yield | %yield=actual yield/theoretical yield x 100 |
To convert mL to L | Multiply by 1000 |
To figure mols/L | L x moles reactant/L |
Oxidation Agent | Species involved in the reduction reaction |
Reduction Agent | Species involved in the oxidation reaction |
Anions | Negative charge; Larger than neutral element because electron cloud is screened by electrons and pull toward nucleus is less |
Cations | positive charge; Smaller than neutral element because more electrons in electron cloud causes nuclear pull to be stronger |
Periodic Trend: Atomic Size | →decreasing↓increasing |
acceleration | the rate of change of velocity; distance/time2 |
Alcohol | a class of organic compounds with the general structure R-OH |
Alkane | a saturated hydrocarbon with the general formula CnH2n + 2 |
Alkene | an unsaturated hydrocarbon that contains a carbon-carbon double bond and has the general formula CnH2n |
ampere (A) | the SI base unit of electric current; 1 A = 1 C/s |
atmosphere (atm) | a non-SI unit of pressure; 1 atm = 1.013250 x 105 Pa |
Avogadro's number (NA) | the number of atoms in exactly 12 grams of carbon-12; NA = 6.0221367 x 1023; the number of things in a mole |
Cation | a positively charged ion |
base SI unit | one of the seven fundamental SI units; the meter (m) for length |
combustion reaction | an exothermic reaction in which a substance is combined with oxygen gas |
density | mass/volume |
dimensional analysis | a method for solving for a quantity by multiplication by conversion factors |
electron | a subatomic particle with a negative charge and a mass of 9.1092897 x 10-31 kg |
exothermic | a process in which energy is given off by a system; q < 0 |
ion | an atom or group of atoms with a net positive or negative charge |
energy | the capacity to do work or transfer heat |
excited state | any energy state of the electron higher than the ground state |
ground state | the lowest available energy state for a given electron |
hydrocarbon | a molecule made up entirely of hydrogen and carbon atoms |
ionic compound | a compound composed of anions and cations |
isomers | compounds with the same molecular formula but with different atomic structures |
isotopes | atoms that have the same number of protons but different numbers of neutrons |
kinetic energy (KE or Ek) | the energy associated with particles in motion; KE = (1/2)mv2 |
linear relationship | a mathematical relationship between two quantities such that as one increases |
mass number | the number of protons and neutrons in the nucleus of a given isotope; the relative atomic mass of a given isotope; the total number of nucleons in an atom |
mole | the amount of substance that contains as many particles as exactly 12 grams of carbon-12; 6.0221367 x 1023 things |
Newton (N) | the SI unit of force; 1 N = 1 kg•m/s2 |
Noble gas | an element from group 18(VIIIA) on the periodic table; an nonreactive element with an entirely filled valence shell |
Oxoacid | an acid that contains oxygen; oxyacid |
pascal (Pa) | the SI unit of pressure; 1 Pa = 1 N/m2 = 9.869233 x 10-6 atm |
HSO3 - | bisulfite |
CO3 2- | carbonate |
C2H3O2 - | acetate |
C2O4 2- | oxalate |
Cr2O7 2- | dichromate |
ClO4 - | perchlorate |
S2O3 2- | thiosulfate |
HClO4 | perchloric acid |
H2SO4 | sulfuric acid |
HSO4 - | bisulfate |
NH4 + | ammonium ion |
CrO4 2- | chromate |
OH- | hydroxide |
O2 2- | peroxide |
HCOO- | formate |
SO4 2- | sulfate |
SO3 2- | sulfite |
CN- | cyanide |
MnO4 - | permanganate |
HNO3 | nitric acid |
HCl | hydrochloric acid |
BaSO4 | barium sulfate – not soluble |
PbSO4 | lead sulfate – not soluble |
CaSO4 | calcium sulfate – not soluble |
Sr(OH)2 | Strontium hydroxide – base - mostly soluble |
Ba(OH)2 | barium hydroxide – base – mostly soluble |
HBr | hydrobromic acid |
HI | hydroiodic acid |
Rb+ | rubidium ion – soluble |
Cs+ | cesium ion – soluble |
K+ | potassium ion – soluble |
Na+ | sodium ion – soluble |
Li+ | lithium ion – soluble |
NO3 - | nitrate – soluble |
HCO3 - | bicarbonate |
SCN - | thiocyanide |
S2O2 2- | thiosulfate |
HgSO4 | mercury sulfate – not soluble |
Pb+ | lead ion – not soluble |
Hg2 2+ | mercury salt – not soluble |
S 2- | Sulfur – slightly soluble |
Ca(OH)2 | calcium hydroxide – strong base – mostly soluble |
PO4 3- | phosphate |
Ideal Gas Law | PV=nRT where P is pressure(atm); V is volume(in L); n is # of moles of gas; R is 0.08206; T is temperature (in K) |
STP | standard temperature and pressure; T is 0°C or 273K; P is 1 atm |
Periodic Trend: electronegativity | →increases ↓decreases |
Periodic Trend: Ionization energy | →increases ↓decreases |
Periodic Trend: electron affinity | →increasingly negative ↓decreasingly negative |
Covalent Bond | when two atoms share electrons |
Ionic bond | when a atom transfers one of it’s electrons to another atom |
Parts per million | mass of solute/total mass of solution x 1 |
Percent by mass | mass of solute/total mass of solution x 100 |
Steps to balance Reduction Oxidation equations in acid | 1.write 2 ½ equations; 2. balance all not O or H; 3. add H20 to balance O; 4. add H+ to balance H in H2O; 5. add electrons to balance charges; 6. balance e- on both sides by multiplying whole ½ equation as needed; 7. Cancel out and re-write. |
Steps to balance Reduction Oxidation equations in base | follow steps for acid and then 1. add OH- to both sides to cancel all H+; 2. combine H+ and OH- to form H2O; 3. add H2O; 4. check atoms and charge for balance. |
Ionization energy | the energy it takes to remove an electron from an atom and make it into an ion. |
Electron affinity | the energy change in an atom when it gains an electron. |
Electronegativity | the ability of an atom to attract an electron of another atom when they are associated through a bond |
Octet rule | states that an atom is more likely to gain electrons the more full it’s valence shell becomes. |
Ionic compounds | high electricity conductors when dissolved in H2O; hard crystals; mostly soluble |
Dissociation | when ionic compounds dissolve into their separate ions in water. |
Sublimation | when a solid is taken into is gaseous form |
Titration | used to find the amount of an unknown substance by adding a known substance to neutralize the unknown. |
Net ionic equation | includes only the species of an equation that is involved in the reaction (reactants → precipitates) |
Enthalpy | E=PV |
Exothermic reaction | when energy is given off by reaction (& heats surroundings) |
Endothermic reaction | when energy is used up by a reaction (& cools surroundings) |