Question

A certain system releases 0.300 kj of heat and has 0.700 kj of work performed on it. What is the value of Δe for the change? Is the overall change exothermic or endothermic?

Answer 1

The change in internal energy (ΔE) of the system is +0.400 kJ, indicating that more energy entered the system than left. The process is therefore endothermic.

Step-by-step explanation:

To determine the change in internal energy (ΔE) of the system given that 0.300 kJ of heat is released (q = -0.300 kJ) and 0.700 kJ of work is performed on it (w = +0.700 kJ), we use the first law of thermodynamics:

ΔE = q + w

Here, a negative value for q indicates heat is released by the system, and a positive value for w indicates work is done on the system. Substituting the given values:

ΔE = (-0.300 kJ) + (+0.700 kJ) = +0.400 kJ

Since the value of ΔE is positive, more energy is entering the system than leaving it, which means the change is endothermic.