AP Chem Units 1-5

Properties of Acids

- Tastes Sour

- Conducts an electrical current

- Reacts with Metals to form Gas

- pH of less than 7

- Turns Litmus Red

Properties of Bases

- Tastes Bitter

- Conducts an electrical current

- Feels slimy/slippery

- pH of more than 7

- Turns Litmus Blue

Arrhenius Acid

Produces H+ ions when dissolved in water

Strong Acids

HCl, HBr, HI, HNO3, H2SO4, HClO4

C (CHOOPS)

Carbonates (CO3 2-)

H (CHOOPS)

Hydroxides (OH-)

O1 (CHOOPS)

Oxides (O)

O2 (CHOOPS)

Oxalates (C2O42−)

P (CHOOPS)

Phospates (PO4 3-)

S (CHOOPS)

Sulfides (S)

N (NAAA)

Nitrates (NO3-)

A (NAAA)

Acetates (C2H3O2-)

A2 (NAAA)

Alkali (Li, Na, K, Rb, Cs, Fr)

A3 (NAAA)

Ammoniums (NH4+)

Arrhenius Base

Produces OH- ions when dissolved in water

Monoprotic Acid

acid with 1 acidic proton

Diprotic Acid

acid with 2 acidic protons

Triprotic Acid

acid with 3 acidic protons

Oxoacids

acidic proton is attached to an oxygen atom

Organic Acids

general formula of R-COOH

Bronsted Acid

substance that can donate a proton

Bronsted Base

substance that can accept a proton

Conjugate Acid

the particle formed when a base gains a hydrogen ion

Conjugate Base

the particle that remains when an acid has donated a hydrogen ion

Amphoteric

a substance that can act as both an acid and a base

Ex of Amphoteric

- H2O

- HSO4 -

- HPO4 2-

- H2PO4 -

Binary Acids

composed of hydrogen and a nonmetal

For Binary Acids, the...

greater the anion radius the smaller the attraction force on the H+ Ion (Smaller Radius = Weaker)

Oxoacid

an acid containing hydrogen, oxygen, and another element (HYO)

For Oxoacids, as you increase the electronegativity of Y and the # of Oxygens...

Strength Increases

Why does adding more Oxygens to Oxoacids increase the strength?

the electron gets pulled closer to Y which weakens the OH bond which increases the strength of the acid

Conjugate Base Strength of Binary Acids

a small radius has a greater ability to attract and accept H+ Ions

[H+] = [OH-]

Solution is NEUTRAL

[H+] > [OH-]

Solution is ACIDIC

[H+] < [OH-]

Solution is BASIC

pH =

-log[H+]

Acid Percent Ionization

[H3O+] (eq)/[HA] (initial) x 100

Base Percent Ionization

[OH-] (eq)/[B] (initial) x 100

Generic Acid BCE

HA + H20 --> (or eq) H30+ + A-

Generic Base BCE

B + H20 --> (or eq) OH- + HB+

Common Ion Effect

a decrease in the solubility of an ionic compound caused by the addition of a common ion

2 Ways to make a Buffer

1-mix a weak acid and salt of its conjugate base or weak base and a salt of its conjugate acid (HA + MA)

2-add strong acid and partially neutralize a weak base or add strong base and partially neutralize a weak acid (B + HB)

Weak Base + Strong Acid

Weak Acid + Strong Base

Strong Acid + Strong Base

Buffer Capacity

the amount of acid or base a buffer solution can absorb without a significant change in pH

Buffering

Kinetics

determines how fast a reaction takes place or the rate of reaction

Example of a SLOW Reaction

Cgraphite -> Cdiamond

Example of a MEDIUM Reaction

4Fe + 3O2 -> 2Fe2O3

Example of a FAST Reaction

CH4 + 2O2 -> CO2 + 2H2O

Rate =

Change in an Observable Quantity/ Change in Time

Rate = Change in an Observable Quantity/ Change in Time =

Change in [Products]/Change in Time = - Change in [Reactants]/ Change in Time

Instantaneous Rate

The rate given at a specific time

How to find Instantaneous Rate

Take the slope of the tangent line at time on the graph

Rate laws

how a rate changes as the initial concentration changes

k

Rate constant

[A]

mole per liter

When the exponents or "order" for a reaction is zero...

the concentration of a reactant has no effect on the reaction rate

0th Order Reaction

Rate=k

If [A] doubles in a 0th order, rate...

stays the same

When m=1

the rxn is 1st order with respects to A

If [A] doubles in a 1st order reaction, then rate...

doubles because they are directly related

1st Order Reaction

rate=k[A]

When m=2

the reaction is 2nd order with respects to A

2nd Order Reaction

Rate=k[A]2

Doubling [A] in a 2nd order reaction, the rate increases by...

4x because concentration is exponentially related to reaction rate

First Order Integrated Rate Law

Second Order Integrated Rate Law

Zero Order Integrated Rate Law

The Straightest Line...

Fits the Order

Collision Theory

The rate of the reaction is proportional to the numer of effective collisions

Factors that effect Orientation

Nature of the Reactants - Molecular Orientation

Temperature

Concentration

Catalysts

As temperature goes up, the nature of the reaction...

goes up since the numberof effe tive collisions goes up

How do you say when the number of effective collisions increases so the molecules require less energy to react?

Molecule's energy to overcome the energy barrier increases

Molecular Kinetic Energy Depends on...

Temperature

Potential Energy Diagram - Endothermic

Potential Energy Diagram - Exothermic

Kinetics Diagram

In General a reaction rate...

doubles every 10 degrees celsius

In a Kinetics Heat Diagram the hottest...

Is always the longest

As temperature increases the probability of finding molecules at higher energy...

increases

Concentration of Solids

As area Increases, effective collisions increases, rxn rate increases

Concentration of Gasses

As V decreases or P increases, effective collisions increase, rxn rate increases

Catalysis

lower the Activation Energy Barrier without becoming consumed or changed in the process

Mechanism

the sequence of steps the molecular level that control the speed of a reaction

Rules for Writing Mechanisms

1. The rate law of the slowest step determines the reactions overall rate law

2. The rate law of a step can be determined by looking at the equation

3. All the steps must add together to give the overall rxn (cross out intermediates)

Rates...

Change during the reaction

Rates are given... by the slope of the line

by the slope of the line

The Equation...

gives average rate over a time interval

Dynamic Equilibrium

Both are being made and destroyed at the same rate

When Slope = 0

equilibrium is achieved

Chemical Equilibrium

the state in which the concentrations of the reactant and products become constant over time

K =

Products/Reactants

K>>1

Lots of products

K<<1

Lots of reactants

K=1

equal amounts of reactants and products

Kc

[products]/[reactants]

Kp

pressure

Ksp

solubility product that are slightly soluble (solids excluded)