Question

Click on the button within the activity and analyze the relationship between the two reactions that are displayed. The reaction that was on the screen when you started and its derivative demonstrate that the reaction enthalpy, ΔH, changes sign when a process is reversed.

Consider the reaction

B(s)+32O2(g)→B2O3(s), ΔH =−1270kJ

What will ΔH be for the reaction if it is reversed?

H Changes sign when a proceSs is reversed