Some properties of a system are state functions.
What is the difference in internal energy of a system, if 100 kJ of energy is radiated out without doing any work?

Internal energy U of a system may change when

What is meant by a change in Gibbs energy of a system?

Some properties of a system are state functions. q and W are not state functions. But (q+W) is a state function. Why?

Calculate the change in internal energy of a system which absorbs 100 J of heat and does 215 J of work.

Internal energy, enthalpy and entropy are thermodynamics state functions. What is enthalpy of a system?

U_1 , q, w, U_2 are given. U_1 is internal energy, q is absorbed heat, w is work done and U_2 is final energy. a) Derive an equation for DeltaU. b) Give the equation for w. c) Calculate the change in internal energy of a system which absorbs 200 J of heat and 315 J of work is done by the system.

Calculate the change in the internal energy of a system which absorbs '500 J' of heat, and does work equivalent to '200 J' on the surroundigs.