Question

The pressure of the gas in a constant volume gas thermometer is $70kPa$ at the ice point. Find the pressure at the steam point.

Answer 1

$P_1=70KPa,P_2=?$

$T_1=273K,T_2=373K$

$T=\frac{P_1}{P_{tr}}\times 273.16$

$\Rightarrow 273=\frac{70\times {10}^3}{P_{tr}}\times 273.16$

$\Rightarrow P_{tr}=\frac{70\times 273.16\times {10}^3}{273}$

$T_2=\frac{P_2}{P_{tr}}\times 273.16$

$\Rightarrow 373=\frac{P_2\times 273}{70\times 273.16\times {10}^3}$

$\Rightarrow P_2=\frac{373\times 70\times {10}^3}{273}=95.6KPa$