Question

At constant temperature and pressure when 8 volumes of dihydrogen gas react with 4 volumes of dioxygen, the mass of water vapour produced is ______.

Options

• 72 g

• 162 g

• 144 g

• 36 g

Answer 1

At constant temperature and pressure when 8 volumes of dihydrogen gas react with 4 volumes of dioxygen, the mass of water vapour produced is 144 g.

Explanation:

\[\ce{2H_{2(g)} + O_{2(g)} -> 2H2O_{(g)}}\]

2 mol       1 mol        2 mol

8 mol       4 mol        8 mol

Mass of H₂O_(g) = no. of moles × molar mass

= 8 × 18 = 144 g