Chapter 12.2, Problem 18SP

Interpretation Introduction

Interpretation: The liters of phosphine are to be determined.

Concept Introduction: According to the law of conservation of mass, the mass can neither be created nor be destroyed. Every reaction must be balanced. With the help of the balanced equation, the limiting reagent can be found and in accordance with it, the amount of product can be calculated.

Answer to Problem 18SP

The required liters of ${\text{P}}_4$ are 0.07 L.

Explanation of Solution

The reaction is given as follows:

  ${\text{P}}_4\left(s\right)+{\text{6H}}_2\left(g\right)\to 4{\text{PH}}_{\text{3}}\left(g\right)$

According to the balanced equation,

  $\begin{array}{c}\text{6}\text{L}\text{of}{\text{H}}_2\to \text{1}\text{L}\text{of}{\text{P}}_4\\ 1\text{L}\text{of}{\text{H}}_2\to \frac{\text{1}}{6}\text{L}\text{of}{\text{P}}_4\\ 0.42\text{L}\text{of}{\text{H}}_2\to \frac{\text{1}}{6}\times 0.42\text{L}\text{of}{\text{P}}_4\\ \to 0.07\text{L}\text{of}{\text{P}}_4\end{array}$

Hence, the required liters of ${\text{P}}_4$ are 0.07 L.