Question

112 cm³ of nitrogen gas is collected at a pressure of 720mm of mercury. If the temperature remains constant, find its volume when the pressure is 20cm of mercury.

Answer 1

Given: P₁ = 720 P₂ = 20cm = 200mm

V₁ = 112 V₂ = ?

Formula: $\frac{{\mathrm{P}}_1{\mathrm{V}}_1}{{\mathrm{T}}_1}=\frac{{\mathrm{P}}_2{\mathrm{V}}_2}{{\mathrm{T}}_2}$

$$\begin{gathered} \frac{720\times 112}{273}=\frac{200\times {\mathrm{V}}_2}{273} \\ \frac{720\times 112}{200}={\mathrm{V}}_2 \\ \frac{80640}{200}={\mathrm{V}}_2 \\ {\mathrm{V}}_2=403.2{\mathrm{cm}}^3 \end{gathered}$$

The volume is 403.2 cm³.