Suka Chemistry: SPM Form 4: Acids and Bases (Checklist)

Acid: A chemical substance which ionizes in water to produce hydrogen ions. An acid will only show its acidic properties when it is dissolved in water. E.g. ethanoic acid CH₃COOH only exhibit acidic properties when water is present.
Alkali: A chemical substance which ionizes in water to produce hydroxide ions. An alkali will only show its alkaline properties when it is dissolved in water. E.g. barium hydroxide, Ba(OH)₃only exhibit alkaline properties when water is present.
A strong acid is an acid that is completely dissociated in an aqueous solution. E.g. HCl (hydrochloric acid), H₂SO₄ (sulfuric acid), HNO₃ (nitric acid).
A weak acid is an acid that is partially dissociated in an aqueous solution. E.g. CH₃COOH
A strong base is a base that is completely dissociated in an aqueous solution. E.g. KOH, NaOH
A weak base is a base that is partially dissociated in an aqueous solution. E.g. NH₄OH
Molarity: The number of moles of solute in 1 dm³ solution. When the molarity of an acid increases, its pH value decreases. When the molarity of an alkali increases, its pH value increases.
pH is a measure of hydrogen ion concentration; a measure of the acidity or alkalinity of a solution. Aqueous solutions at 25°C with a pH less than seven are acidic, while those with a pH greater than seven are basic or alkaline. A pH level of is 7.0 at 25°C is defined as 'neutral' because the concentration of H₃O⁺ equals the concentration of OH⁻ in pure water.
The two factors which determine the pH value of an acid or an alkali are degree of ionization and concentration of the acid or alkali.
Neutralization: A reaction between an acid and an alkali or a base to produce salt and water.
Acid-base titration: A quantitative analysis to determine the volume of an acid required to exactly neutralize a fixed volume of an alkali with the help of a suitable indicator.
End-point: A stage achieved in titration where the volume of acid added exactly neutralizes a fixed volume of an alkali.