Question 9 What do you know about a chemical reaction if the value of Delta H is negative? The reaction is exothermic. The reaction is endothermic. The reaction occurs without the addition of energy. The reaction cannot occur at room temperature. 1 pts

In thermodynamics, the enthalpy change ( ) of a reaction signifies the heat absorbed or released during a chemical reaction at constant pressure. A negative indicates that the reaction releases heat to the surroundings, making it exothermic. This is a key concept distinguishing between exothermic (heat-releasing, negative ) and endothermic (heat-absorbing, positive ) reactions.