CHAPTER 10: Acids, Bases & Salts

What is an Arrhenius acid?

A substance that contains hydrogen and produces H⁺ in aqueous solution.

What is an Arrhenius base?

A substance that contains OH and produces OH⁻ in aqueous solution.

What is a neutralization reaction (Arrhenius)?

H⁺ + OH⁻ → H₂O

List of strong acids

HCl, HBr, HI, H₂SO₄, HNO₃, HClO₄, HClO₃

List of strong bases

LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)₂, Sr(OH)₂, Ba(OH)₂

Why do we write H₂O⁺?

Free protons don’t exist in water; they attach to water to form the hydronium ion

What is a polyprotic acid?

An acid that can donate more than one H⁺ (example: H₃PO₄).

Where are acidic H atoms located in oxyacids?

Attached to oxygen, not the central atom (e.g., H–O–X bonds).

Brønsted–Lowry acid definition

Proton donor

Brønsted–Lowry base definition

Proton acceptor.

What is a conjugate acid?

Species formed when a base gains a proton.

What is a conjugate base?

Species formed when an acid loses a proton.

Relationship between strength of conjugate pairs?

Strong acid → weak conjugate base
Strong base → weak conjugate acid
Weak acid ↔ weak base pair

What is autoionization of water?

H₂O + H₂O → H₂O⁺ + OH⁻

[H₂O⁺] and [OH⁻] in pure water?

Both = 1.0 × 10⁻⁷ M

What does amphoteric mean?

A species that can act as an acid or a base.

What does amphiprotic mean?

A species that can donate or accept a proton.

Example of amphoteric species from chapter?

HSO₄⁻ can act as an acid or base.

Lewis acid definition

Electron-pair acceptor.

Lewis base definition

Electron-pair donor.

What forms during Lewis neutralization?

A coordinate covalent bond.

Example of a Lewis-acid-only reaction

NaF + BF₃ → Na⁺ + BF₄⁻ (involves no H⁺ transfer).

Why is BF₃ a strong Lewis acid

It has an incomplete octet and can accept an electron pair.

Why can metal ions act as acids in water?

They form hydrated complexes that can release H⁺.

Are metal-hydroxide complexes amphoteric?

Yes, they can act as acids or bases.

What determines strength of binary acids (HX)?

weaker H–X bond → stronger acid.

Trend of binary acids HF → HI

Bond length ↑
Bond strength ↓
Acid strength ↑
Strongest = HI

What determines strength of oxyacids?

Number of oxygen atoms — more oxygen → stronger acid.

Why do more oxygens increase acid strength?

More delocalization of negative charge → more stable conjugate base.

How are binary acids made?

React nonmetals with H₂ (with UV light). Example: H₂ + Cl₂ → 2HCl

How are oxyacids made?

React nonmetal oxides with water. Example: SO₂ + H₂O → H₂SO₃

How are bases made?

React metal oxides with water → metal hydroxides.

What is an acidic salt?

Salt formed when a polyprotic acid is partially neutralized.

Example of acidic salt formation

H₂SO₄ + NaOH → NaHSO₄ + H₂O

What is a basic salt?

Salt formed when a polyhydroxy base is partially neutralized.

Example of basic salt formation

Ba(OH)₂ + HCl → Ba(OH)Cl + H₂O

Strong acid = strong or weak conjugate base?

Weak conjugate base.

Which acid is strongest: HF, HCl, HBr, HI?

HI

What theory defines acids as proton donors?

Brønsted–Lowry.

What theory defines acids as electron-pair acceptors?

Lewis.

What ion exists at 1.0 × 10⁻⁷ M in pure water?

Both H₂O⁺ and OH⁻.