Question

QUESTION 5 [20] 5.1 What does pH measure? (1) 5.2 Differentiate between an acid and a base in terms of their pH values. (2) 5.3 Identify salts, acids and bases applied in the following: 5.3.1 Used as an electrolyte in lead-car batteries (1) 5.3.2 Used as a cleaning agent (1) 5.3.3 Used in drain and oven cleaners (1) 5.3.4 Used in antacids to relieve indigestion (1) 5.4 Complete the following table for bases and acids by giving the answers for 5.4.1 – 5.4.3: (3) Chemical name Formula 5.4.1 H3PO4 Sodium hydrogen carbonate 5.4.2 5.4.3 CH3COOH 5.5 Complete the following sentences: 5.5.1 A substance that change colour in the presence of an acid or base ___________ (1) 5.5.2 Bromothymol blue turns ___________in acids and turns ___________ in alkalis. (1) 5.5.3 Red litmus paper turns ___________in a basic media. (0.5) 5.5.4 Blue litmus paper turns ___________in an acid media. (0.5) 5.5.5 Rice grows best in ___________ soil. (1) 5.6 What are the products of the following chemical reactions? 5.6.1 NaOH (aq) + H20 (aq) → (2) 5.6.2 HCl (aq) + H20 (aq) → (2) 5.7 Complete the following table for common salts by stating the answers for 5.7.1 and 5.7.1: (2) Formula Common name 5.7.1 Washing soda NaHCO3 5.7.2

Answer 1