Chem Acids and bases 14.1-14.3

Write equations for acid- and base-ionization reactions

Generic Acid-Ionization

HA(aq) + H2O(l) ⇌ A-(aq) + H3O+(aq)

NH3 is a weak

Acid, ammonia

NH4Cl is a

Strong acid Ammonium Cloride

Write equations for acid- and base-ionization reactions

Generic Base-Ionization:

B(aq) + H2O(l) ⇌ HB+(aq) + OH-(aq)

What is an amphoteric (amphiprotic) substance?

Substances that can act as either acids (H+ donors) or bases (H+ acceptors)

Calculate [H3O+] and [OH-] using the ion-product constant for water and explain how these concentrations relate to pH, pOH, and characterization of acids & bases

Calculate [H3O+] and [OH-] using the ion-product constant for water and explain how these concentrations relate to pH, pOH, and characterization of acids & bases

a compound that donates a proton (H+) to another

Brønsted-Lowry acid

a compound that accepts a proton (H+) from another

Brønsted-Lowry base

reaction between a Brønsted-Lowry acid and H2O

acid-ionization

reaction between a Brønsted-Lowry base and H2O

base-ionization

describes a substance that can either donate a H+ or accept a H+

amphiprotic

a substance that can acid as either an acid or base

amphoteric

process in which like molecules react to yield ions

autoionization

If [H3O+] > [OH-], the solution is

acidic.

If [H3O+] < [OH-], the solution is

basic

If [H3O+] = [OH-], the solution is

neutral

Recognize strong acids & bases and assess their relative strengths based on their ionization constants

Recognize strong acids & bases and assess their relative strengths based on their ionization constants

Perform equilibrium calculations for weak acid-base systems

Recognize strong acids & bases and assess their relative strengths based on their ionization constants

Strong acids & bases ionize

completely

Weak acids and bases ionize

partially

strong electrolytes ionize

completely in solution

Weak electrolytes ionize

partially in solution

How do we determine how completely an acid or base ionizes?

Based on their equilibrium constants (Ka or Kb)

Remember that for K values, all concentrations are those

at equilibrium

In aqueous solution, the stronger the acid or base

the weaker its conjugate

The strength of an acid or base is determined by how

well the substance ionizes.

The greater the degree of ionization =

stronger acid/base. (Compare Kas and Kbs!)

The stronger the acid, the weaker

its conjugate base;

the weaker the acid, the stronger

its conjugate base

The stronger the base, the weaker

its conjugate acid;

The weaker the base, the stronger

its conjugate acid.

Strong acids HClO4

perchloric acid

Strong acids HCl

hydrochloric acid

Strong acids HBr

hydrobromic acid

Strong acids Hl

Hydroiodic acid

Strong acids HNO3

nitric acid

Strong acids H2SO4

sulfuric acid

Strong bases LiOH

lithium hydroxide

Strong bases NaOH

sodium hydroxide

Strong bases KOH

potassium hydroxide

Strong bases Ca(OH)2

calcium hydroxide

Strong bases Sr(OH)2

strontium hydroxide

Strong bases Ba(OH)2

barium hydroxide

% Ionization for Acids

[H3O+]eq / [HA]0 ×100

What species can act like an acid and base

HCO3- AND H2O

% Ionization of base

[OH-]eq/ [B]0 × 100%

Acid ionization constant Ka

[H30+][A-] // [HA]

Base ionization constant Kb

[HB+][OH-] // [B]

The Ka for a strong acid or base is

high

When Ka increases Kb will

decrease, they are inversley related

Kw constant

1.0 × 10-14