Question

Is $∆H$ positive or negative?

Answer 1

The enthalpy change is a measure of the amount of heat absorbed or released during a chemical reaction carried out at a constant pressure. $∆H$ can be negative or positive.

1. $∆H$ is positive: the products have a higher energy level than the reactants and the reaction was endothermic, absorbing net heat.
2. $∆H$ is negative: the products have less energy than the reactants. An exothermic reaction produced net heat.

Hence, $∆H$ is both negative and positive.