Question

The pressure of a gas at -173 degree celsius is one atmosphere.Keeping the volume constant,to what temperature should the gas be heated so that the pressure becomes two atmosphere?

Answer 1

According to Gay Lussac's law, at constant volume, the pressure and the temperature is related as,
$P\alpha T$
that is,
$\frac{P_1}{T_1}=\frac{P_2}{T_2}$
Now as per given data, P₁ = 1 atm, P₂ = 2 atm, T₁ = -173^o C = 273 + (-173^o C) = 100 K and T₂ = ?
On substituting the values in the above equation we get,
$$\begin{gathered} \frac{1atm}{100K}=\frac{2atm}{T_2} \\ \frac{1}{100K}=\frac{2}{T_2} \\ i.e.,T_2=200K \end{gathered}$$