What is the change in internal energy if 50 j of heat are released from a system, and the system does 80 j of work on its surroundings?

An insulated 40 ft^3 rigid tank contains air at 50 psia and 120°f. a valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 25 psia. the air temperature during this process is kept constant by an electric resistance heater placed in the tank. determine the electrical work done during this process.

What are the starting materials for nuclear fission? two small nuclei two large nuclei a neutron and a large nucleus a neutron and a small nucleus

Atank is filled with an ideal gas at 400 k and pressure of 1.00 atm . part a the tank is heated until the pressure of the gas in the tank doubles. what is the temperature of the gas?