The change in the internal energy of a system that absorbs 2,500 J of heat and that does 7,655 J of work on the surroundings is ________ J.
A)10,155
B)5,155
C)-5,155
D)-10,155
E)1.91 ×

Question

The change in the internal energy of a system that absorbs 2,500 J of heat and that does 7,655 J of work on the surroundings is ________ J.
A)10,155 
B)5,155 
C)-5,155 
D)-10,155 
E)1.91 ×

Quizplus · Accepted Answer

The first law of thermodynamics states that the change in internal energy of a system (ΔU) is equal to the heat absorbed (Q) minus the work done by the system (W): ΔU = Q - W. In this case, ΔU = 2500 J - 7655 J = -5155 J. The negative sign indicates that the internal energy of the system has decreased, meaning that energy has been released from the system (in the form of work done on the surroundings). Therefore, the correct answer is C, -5,155 J.

The Change in the Internal Energy of a System That