Chapter 3: Atoms and Molecules

Q1. Find the molecular mass of H₂SO₄.

Solution

H: 2 × 1 = 2
S: 1 × 32 = 32
O: 4 × 16 = 64
Total = 98 u

Q2. How many molecules are present in 18 g of water?

Solution

Moles = 18/18 = 1 mol
Molecules = 1 × 6.022 × 10²² = 6.022 × 10²² molecules