Question

5.Convert into mole.(Atomic mass O=16u ; H=1u)


(a) 12 g of oxygen gas

(b) 20 g of water​

Answer 1

Explanation:

(a) Molecular weight of oxygen in grams = 32 g of oxygen= one mole of oxygen gas

Thus, 12 g of oxygen=

32

1

×12=0.375 moles

(b) Molecular weight of water (H

2

O) in grams= 2+ 16=18 g=one mole of water

Thus, 20 g of water=

18

1

×20=1.111 moles

(c) Molecular weight of carbon dioxide (CO

2

) in grams=12+2×16=44 g=one mole of carbon dioxide

Thus, 22 g of carbon dioxide =

44

1

×22=0.5 moles