Acids and Bases Classification

Classification of Acids

• Organic Acids: derived from plants, e.g. citric, oxalic, tartaric, acetic acid
• Inorganic Acids: derived from minerals, e.g. HCl, H2SO4, HNO3

Classification of Acids by Molecular Composition

• Hydracids: contain hydrogen and a non-metallic element other than oxygen, e.g. HCl, HBr, HI
• Oxyacids: contain hydrogen, another element, and oxygen, e.g. HNO3, H2SO4

Strength of Acids and Bases

Strength of Acids

• Depends on concentration of hydronium ions (H3O+) in an aqueous solution
• Strong Acid: dissociates almost completely, producing high concentration of hydrogen (H+) ions, e.g. HNO3, H2SO4, HCl
• Weak Acid: dissociates only partially, producing low concentration of hydrogen (H+) ions, e.g. CH3COOH

Strength of Alkalis

• Depends on concentration of hydroxyl ions (OH-) in an aqueous solution
• Strong Alkali: dissociates almost completely, producing high concentration of hydroxyl (OH-) ions, e.g. NaOH, KOH
• Weak Alkali: dissociates only partially, producing low concentration of hydroxyl (OH-) ions, e.g. NH4OH

Concentration of Acids and Bases

Concentrated Acids and Alkalis

• Concentrated Acid: has a relatively high percentage of acid in its aqueous solution
• Concentrated Alkali: has a relatively high percentage of alkali in its aqueous solution

Dilute Acids and Alkalis

• Dilute Acid: has a relatively low percentage of acid in its aqueous solution, concentration less than 1 mol/litre
• Dilute Alkali: has a relatively low percentage of alkali in its aqueous solution, concentration less than 1 mol/litre