Question

What is the mass of: [3 MARKS]

1. 0.2 mole of elemental oxygen atom
2. 0.5 mole of water molecules
3. 2 mole of cabon dioxide

Answer 1

Each point: 1 Mark

1. Mass of one mole of elemental oxygen atom = 16 g
Then, mass of 0.2 mole of oxygen atoms = 0.2 x 16g = 3.2 g

2. Mass of one mole of water molecule = (2 x 1 g)+ 16 g =18 g
Then, mass of 0.5 mole of water molecules = 0.5 x 18 g = 9 g

3. Mass of one mole of carbon dioxide molecule = 12 g + (2 x 16 g) = 44 g
Then, mass of two mole of carbon dioxide molecule = 2 x 44 g = 88 g