Recently Added Formulas in Chemistry

· Hydrolysis
· Ionization
· pH scale
· Acid-base Reaction
· Strength of Acid and bases

Additional Formulas

· Acid and Base
· Bronsted/Lowry theory
· Strength of Acid and bases
· Acid-base Reaction
· pH scale
· Buffers
· Ionization
· Hydrolysis

Current Location > Formulas in Chemistry > Acid and Bases > Acid and Base

Acid and Base

ACIDS

Definition & Properties:
Acids are the compounds which has
· Sour taste
· Turns litmus blue to red
· Gives hydrogen ion in solution
· Reacts with metals to release flammable gas

Examples: Hydrochloric acid (HCl), Sulphuric acid (H₂SO₄), Acetic acid (CH₃COOH)

Reaction: HCl → H⁺ + Cl^-
H₂SO₄ → 2H⁺ + SO^4-
CH₃COOH → H⁺ + CH₃COO^-

BASES

Definition & Properties:
Bases are the compounds which has
· Bitter taste
· Turns litmus red to blue
· Gives hydroxide ion in solution
· Soapy in nature

Examples: Sodium hydroxide (NaOH), Potassium hydroxide (KOH)

Reaction: NaOH → Na⁺ + OH^-
KOH → K⁺ + OH^-

Theories of Acid and Base

Arrhenius theory:

Arrhenius acid: Substance that produces H⁺ ion in solution
Example: HCl
Arrhenius base: Substance that produces OH^- ion in solution.
Example: NaOH

Limitation:
1. Definition is based on aqueous condition only.
2. Substance should contain H⁺ and OH^- ion. Substances which do not contain H⁺ and OH^- ion can not be explained by Arrhenius theory.
Example: AlCl₃ acts as acid in aqueous solution and NH₃ acts as a base.
3. Theory is unable to explain the acidic and basic characters of substances in nonaqueous condition.
Example: NH₄NO₃ in ammonia

More Examples:
For a chemical reaction:

Where:
A: acid
B: base

To determine the strength of the acid, we use the acid dissociation constant, which is given by:

For a chemical reaction:

Where:
A: acid
B: base

To determine the strength of the base, we use the base dissociation constant, which is given by: