A constant volume and mass of helium gas at 77°C is heated so that the pressure of the gas doubles. What is the new temperature of the gas in Celsius degrees?

427°C .

Explanation:

Step 1:

Data obtained from the question. This include the following:

Initial temperature (T1) = 77°C

Initial pressure (P1) = P

Final pressure (P2) = 2P

Final temperature (T2) =?

Step 2:

Conversion of celsius temperature to Kelvin temperature.

This is illustrated below:

T(K) = T (°C) + 273

Initial temperature (T1) = 77°C

Initial temperature (T1) = 77°C+ 273 = 350K

Step 3:

Determination of the new temperature. The new temperature can be obtained as follow:

P1/T1 = P2/T2

P/350 = 2P/T2

Cross multiply

P x T2 = 350 x 2P

Divide both side by P

T2 = (350 x 2P ) / P

T2 = 700K

Step 4:

Conversion of Kelvin temperature to celsius temperature.

This can be obtained as follow:

T(°C) = T(K) – 273

T(K) = 700K

T(°C) = 700 – 273

T(°C) = 427°C

Therefore, the new temperature of the gas is 427°C