A system undergoes a two-step process. In the first step, the internal energy of the system increases by 218 J when 170 J of work is done on the system. In the second step, the internal energy of the system increases by 107 J when 172 J of work is done on the system.

1. For the overall process, find the heat?

2. What type of process is the overall process? Explain.

1) Q total = Q1 + Q2 = 48 J + (-65J) = (-17J)

2) since the total heat exchanged is negative, the overall process is a cooling process

Explanation:

According to the first law of thermodynamics

ΔE = Q - W

where ΔE = change in internal energy, Q = heat and W = work done by the system to the surroundings

in the first step

Q1 = ΔE + W = 218 J + (-170 J) = 48 J

in the second step

Q2 = ΔE + W = 107 J + ( - 172 J) = - 65 J

the total heat is

Q total = Q1 + Q2 = 48 J + (-65J) = (-17J)

since the total heat exchanged is negative, the overall process is a cooling process.