Question

The mercury manometer shown in the figure (Figure 1) is attached to a gas cell. The mercury height h is 120 mm when the cell is placed in an ice-water mixture. The mercury height drops to 30 mm when the device is carried into an industrial freezer. What is the freezer temperature? The mercury manometer shown in the figure (Figure 1) is attached to a gas cell. The mercury height h is 120 mm when the cell is placed in an ice-water

Answer 1

$P_{1}V_{1}=nRT_{1}$

$P_{2}V_{2}=nRT_{2}$

$\frac{P_{1}}{T_{1}}=\frac{nR}{V_{1}}$

$\frac{P_{2}}{T_{2}}=\frac{nR}{V_{2}}$

$\frac{P_{_{1}}}{T_{1}}=\frac{P_{_{2}}}{T_{2}}$

$T2=T_{1}\frac{P_{2}}{P_{1}}\; \; \; \; \; eqa(1)$

$T2=T_{1}\frac{P_{2}}{P_{1}}$

$T2=T_{1}\frac{P_{bg} + P_{2g}}{P_{bg} + P_{1g}}$

$T2=273.15K\times \frac{760 + 30}{760+ 120}$

$\mathbf{T_{2} = 245.2 \; Kelvin}\; \; \; (Ans)$

$OR \; \; \; \mathbf{T_{2} = -27.9 Celsius}$