What volume of hydrogen is formed by the interaction of 9.2 g of ethanol with metallic sodium, if vx = 90%.

Given:
m (C2H5OH) = 9.2 g
φ out. = 90%
Vm = 22.4 l / mol

To find:
V practical. (H2) -?

Decision:
1) 2C2H5OH + 2Na => 2C2H5ONa + H2 ↑;
2) M (C2H5OH) = Mr (C2H5OH) = Ar (C) * 2 + Ar (H) * 6 + Ar (O) = 12 * 2 + 1 * 6 + 16 = 46 g / mol;
3) n (C2H5OH) = m (C2H5OH) / M (C2H5OH) = 9.2 / 46 = 0.2 mol;
4) n (H2) = n (C2H5OH) / 2 = 0.2 / 2 = 0.1 mol;
5) V theor. (H2) = n (H2) * Vm = 0.1 * 22.4 = 2.24 L;
6) V practical. (H2) = φ out. * V theor. (H2) / 100% = 90% * 2.24 / 100% = 2.02 HP

Answer: The volume of H2 is 2.02 liters.