The second reaction is obtained from the first when the first reaction is divided by 2 and reversed. The enthalpy change for the second reaction is -18 kJ.
What is enthalpy?
The term enthalpy is defined as the heat absorbed or evolved in a reaction. It could be positive or negative.
If we look at the two reactions as shown in the question, we can see that the second reaction is obtained from the first when the first reaction is divided by 2 and reversed.
Hence, it the follows that the enthalpy change for the second reaction is -18 kJ.
Learn more about enthalpy: https://brainly.com/question/365923
