Question

One mole of Calcium phosphide on reaction with excess water gives:

• A. $1\mathrm{mol}$ Of Phosphine
• B. $2\mathrm{mol}$ Of Phosphine
• C. $2\mathrm{mol}$ Of Phosphoric Acid
• D. $1\mathrm{mol}$ Of Phosphorus Pentaoxide

Answer 1

The correct option is B

$2\mathrm{mol}$ Of Phosphine

Explanation for Correct answer:

Option (B) $2\mathrm{mol}$ Of Phosphine

• One mole of Calcium phosphide on reaction with excess water gives $2\mathrm{mol}$ of Phosphine (${\mathrm{PH}}_3$​) gas and $3\mathrm{mol}$ of Calcium hydroxide ($\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$​).

$\underset{\mathrm{Calcium}\mathrm{phosphide}}{{\mathrm{Ca}}_3{\mathrm{P}}_2\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{6{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Calcium}\mathrm{hydroxide}}{3\mathrm{Ca}{\left(\mathrm{OH}\right)}_2\left(\mathrm{aq}\right)}+\underset{\mathrm{Phosphine}}{2{\mathrm{PH}}_3\left(\mathrm{s}\right)}$

Therefore, one mole of Calcium phosphide on reaction with excess water gives $2\mathrm{mol}$ Of Phosphine, so option (B) is correct.