AP Chem Bible

Strong acids

HCl, HBr, HI, HNO3, H2SO4, HClO4 — all others are weak

Strong bases

Group I and II hydroxides

How to determine largest dipole moment

Greatest difference in electronegativity OR greatest distance apart on the periodic table

Hybridization: linear

sp

Hybridization: trigonal planar

sp2

Hybridization: tetrahedral

sp3

Hybridization: trigonal bipyramidal

sp3d

Hybridization: octahedral

sp3d2

What determines hybridization?

Electron domains (lone pairs + sigma bonds) — pi bonds do NOT count

Single bond sigma/pi

1 sigma, 0 pi

Double bond sigma/pi

1 sigma, 1 pi

Triple bond sigma/pi

1 sigma, 2 pi

Always soluble in water

All alkali metals, NH4+, NO3-, and acetate (C2H3O2-)

Metal placed in acid produces…

H2 gas + aqueous salt; negative ion is the spectator ion

Groups 1 & 2 metals in water produce…

H2 gas and a base (which usually ionizes)

Carbonate reactions always produce…

CO2 and a metal oxide

Rate constant k units: 0th order

M/s

Rate constant k units: 1st order

s-1

Rate constant k units: 2nd order

M/s-1 (M-1s-1)

Rate constant k units: 3rd order

M2/s-1 (M-2s-1)

Lighter vs heavier atoms at same temperature

Lighter atoms move/effuse faster, but ALL atoms at the same temp have the SAME kinetic energy

Two factors behind periodic trends

Zeff (effective nuclear charge) and energy level

IMFs and physical properties

Stronger IMFs = higher boiling point, freezing point, viscosity, vapor pressure. Key factor: POLARIZABILITY

Covalent network solids

C (diamond) and Si — held by coordinate covalent bonds throughout; very strong

Entropy order

Gases > Liquids > Solids

In Ksp, what is x?

x is the molar solubility

LEO the lion says GER

Loss of Electrons = Oxidation; Gain of Electrons = Reduction

Bond order formula

Bond order = # of bonds / # of bonding sites

When are gases most ideal?

High temperature and low pressure

Enthalpy calculation formula

Products - Reactants (EXCEPT bond energy: use Reactants - Products)

Colors: iodine, MnO4-, Cu2+, transition metals

Iodine = purple, MnO4- = purple, Cu2+ = blue, transition metals = greens/blues

Ionic vs molecular compounds — state of matter

All ionic compounds are solids; molecular compounds are usually liquids or gases

Strong electrolytes

Ionic compounds and strong acids

Weak electrolytes

Weak acids and bases

Non-electrolytes

Molecular compounds

Electrons jumping down energy levels

Emit energy (as light/color)

Electrons jumping up energy levels

Absorb energy

Exothermic vs endothermic feel

Exothermic = releases energy (feels warm); Endothermic = absorbs energy (feels cool)

Why is a molecule polar?

It has a net dipole moment

Geometries that are always polar

Bent and trigonal pyramidal (lone pairs cause asymmetry)

Substitutional vs interstitial alloys

Substitutional = same size; Interstitial = different sizes

Slow step is step 2 in mechanism — rate law?

Cancel the intermediate, combine reactants from both steps

Le Chatelier's Principle

A disruption shifts equilibrium toward the side that relieves the disruption

Temperature unit for gas problems

Always Kelvin (K)

Constant half-life = what reaction order?

First order

Kc vs Kp notation

Kc uses [ ] brackets (concentrations); Kp uses P (partial pressures) — never brackets for Kp

Cations migrate to… Anions migrate to…

Cations → cathode (+); Anions → anode (-)

Cathode vs anode reaction

Cathode = reduction; Anode = oxidation

Acid to water safety rule

Acid to water, you oughta! (Never water to acid)

Temperature increase effect on Kw and pH

Kw increases, pH decreases

Temperature decrease effect on Kw and pH

Kw decreases, pH increases

DG+, Ecell-, K<1 means…

Nonspontaneous reaction

DG-, Ecell+, K>1 means…

Spontaneous reaction

DG=0, Ecell=0, K=1 means…

System at equilibrium

DH(-) DS(+): spontaneity?

Always spontaneous at all temperatures

DH(+) DS(-): spontaneity?

Never spontaneous; reverse reaction always spontaneous

DH(-) DS(-): spontaneity?

Spontaneous at low T; nonspontaneous at high T

DH(+) DS(+): spontaneity?

Nonspontaneous at low T; spontaneous at high T