(a) Under what condition will the enthalpy change of a process equal the amount of heat transferred into or out of the system? (b) During a constant-pressure process, the system releases heat to the surroundings. Does the enthalpy of the system increase or decrease during the process? (c) In a constant-pressure process, _x001F_H = 0. What can you conclude about _x001F_E, q, and w?

Verified step by step guidance

1. Step 1: Understand the relationship between enthalpy change (ΔH) and heat transfer (q) in thermodynamics. Enthalpy change equals the heat transferred into or out of the system at constant pressure. Therefore, ΔH = q when the process occurs at constant pressure.
2. Step 2: For part (b), consider the scenario where the system releases heat to the surroundings at constant pressure. According to the first law of thermodynamics, if the system releases heat, q is negative. Since ΔH = q at constant pressure, the enthalpy of the system decreases.
3. Step 3: For part (c), analyze the condition where ΔH = 0 in a constant-pressure process. This implies that there is no net heat transfer into or out of the system, meaning q = 0.
4. Step 4: Use the first law of thermodynamics, ΔE = q + w, where ΔE is the change in internal energy and w is the work done on or by the system. Since q = 0, ΔE = w.
5. Step 5: Conclude that if ΔH = 0 and q = 0, then the work done (w) is the only contributor to the change in internal energy (ΔE). Therefore, ΔE = w, indicating that any change in internal energy is due to work done on or by the system.