Question

You are given \(\Delta H\) for a process that occurs at constant pressure. What additional information do you need to determine \(\Delta E\) for the process?

Short answer

To determine the change in internal energy (ΔE) for a process occurring at constant pressure, given the enthalpy change (ΔH), we need to know the constant pressure (P) and the change in volume (ΔV) for the process. We can then use the relationship \(ΔH = ΔE + PΔV\) to calculate ΔE.

Step-by-step solution

Understand the relationship between ΔH, ΔE, pressure, and volume

For a process at constant pressure, we can use the relationship between enthalpy change (ΔH) and internal energy change (ΔE) to find ΔE. The relationship is given by the following formula: \[ΔH = ΔE + PΔV\] Here, P is the constant pressure, and ΔV is the change in volume.

Identify the required additional information

To determine ΔE, we will need to know the values of the following parameters: 1. The constant pressure (P) of the process 2. The change in volume (ΔV) during the process Since we already have been given ΔH, we only lack these two parameters to calculate ΔE using the formula mentioned in Step 1.

Conclusion

In order to determine the change in internal energy (ΔE) for a process occurring at constant pressure, given the enthalpy change (ΔH), we need to know the constant pressure (P) and the change in volume (ΔV) for the process.