Question

An insulated tank initially contains 0.25 kg of a gas with an internal energy of 200 kj/kg. Additional gas with an interanl energy of 300 kj/kg and an enthalpy of 400 kj/kg enters the tank until the total mass of gas contained is 1 kg. The final internal energy (in kj/kg) of the gas in the tank is

Answer 1

Given: Quantity of gas = 0.25 kg

Internal energy = 200kg

Additional gas = 300kg

Enthalpy entering the tank = 400kg

To Find: Internal energy of gas in the tank

Solution:

U = u1m1 + ( 1-m1 )h

U = 200 . 0.25 + ( 1 - 0.25) . 400

= 350

U = 350

Answer: The final internal energy is 350 kJ.