THERMO 2 In order to determine cp for an unknown ideal gas 0

THERMO 2

In order to determine c_p for an unknown ideal gas, 0.1 kg of its mass is deposited into an adiabatic piston–cylinder–weight assembly and electrically heated by a current of 0.26 A at 120V for a duration of 30 seconds. The resultant temperature rise is measured to be 10 ºC. Calculate c_p, assuming it to be constant.

Solution

Equating heat contained = heat supplied

m*cp*(dT/dt) = V*i

cp = V*i*t/(m*deltaT) = 936 J/Kg.K