Question

In the electrolysis of water, 2H2O → 2H2 + O2, if the volume of oxygen produced was 8 mL, what would be the volume of hydrogen produced?
a. 4 mL
b. 8 mL
c. 16 mL
d. 24 mL

Answer 1

Answer:

16ml

Explanation:

2H2O → 2H2 + O2

2mol      2mol     1mol

volume of oxygen produced =8ml

1mole of a gas contains 22.4dm³

8ml will be equal to 8ml/22.4dm³  number of moles of oxygen gas

Using the stoichoimetric co-efficients;2moles of H2 and 1mol of Oxygen were produced

so number of moles of hydrogen will be [(2*8ml)/22.4dm³moles

but 1mol contains 22.4dm³

[(2*8ml)/22.4dm³moles   will contain x

cross multiply;

x= (2*8ml)mol/22.4dm³ *22.4dm³/1mol

x=16ml

simply put ; using the stochoimetric coefficients if 2moles of H2 correspond to 1mol of O2, thus 16ml of H2 will correspod to 8ml of O2.