chemistry

concentration volume relation

c1*v1 = c2*v2

ppm

(mass of trace substance*10^6)/mass of sample

ppb

(mass of trace substance*10^9)/mass of sample

calorimetry

Q=m*c* ΔT

pH

pH = -log[H+]

gibbs free energy

ΔG=ΔH-TΔS

ΔG = change in Gibbs free energy (kJ/mol)
→ Tells you whether a reaction is spontaneous.

• ΔH = change in enthalpy (kJ/mol)
  → Heat absorbed or released.

• T = temperature in Kelvin (K)

• ΔS = change in entropy (kJ/mol·K)
  → Measure of disorder/randomness.

Equilibrium Constant and Free Energy

k = e^- ΔG/RT

• K = equilibrium constant

• ΔG° = standard Gibbs free energy change (in J/mol or kJ/mol)

• R = universal gas constant = 8.314 J/mol·K

• T = temperature in Kelvin

• e = Euler’s number (≈ 2.718)

orbitals

1s2

2s2 sp6

3s2 sp6 3d10

4s2 4p6 4d10

ionic bond

complete transfer of one or more valence electrons

polar covalent bond

bonding electrons shared unequally, partial charges on atoms

non polar covalent bond

bonding atoms shared equally between atoms, no charge on atoms

percentage yield

=(actual yield/theoretical yield )*100

atom economy

(mass of atoms in desired product/total mass of reactant atoms)*100

identify limiting reactants

• Convert to moles

• Compare actual mole ratio to the required mole ratio

  • Whichever reactant can produce less product (or runs out first) is limiting

reduction

gains electrons

oxidation

loses electrons

balancing redox equations

1 Ensure each half cell is balanced with respect to elements and charge on each side

2 Combine the reactions, balancing the number of electrons

3 Cancel the electrons out.

balance the reaction MnO4- + H+ + e- = Mn2+ + H2OO

MnO4- + 8H+ + 5e- = Mn2+ + 4H2O

HEAT change

q = m*c*ΔT

ideal gas equation

PV = nRT

van der waals equation

(P+an² / v² ) (V-nb) = nRT

daltons partial pressure laws

pp(gas) = p(tot) * X (gas)

x(gas) = moles of gas/total number of moles

chemical equilibrium constant

K = exp(-ΔG/RT) = exp(-ΔH/RT)* exp(ΔS/R)

le chateliers principle

Kc = ((C)^c *(D)^d)/ ((A)^a *(B)^b

Kc(T)>1000

reaction goes to completion

Kc(T)<0.001

no reaction