Question

Convert into mole.

(a) 12 g of oxygen gas

(b) 20 g of water

(c) 22 g of carbon dioxide

Answer 1

The mass of one mole of a substance is equal to that substance's molecular weight. For example, the mean molecular weight of water is 18 atomic mass units (amu), so one mole of water weighs 18grams.

(a) 32 g of oxygen gas = 1 mole

Then, 12 g of oxygen gas == 0.375 mole

(b) 18 g of water = 1 mole

Then, 20 g of water == 1.11 moles (approx)

(c) 44 g of carbon dioxide = 1 mole

Then, 22 g of carbon dioxide == 0.5 mole