Question

What is the meaning of a value of –400 kJ in a reaction? The reaction requires 400 kJ of heat. The reaction releases 400 kJ of heat. The products have 400 kJ of heat energy more than the reactants. The reaction will not occur.

Answer 1

does it mean the reaction was exothermic (I am not too sure but that's what I think)

Answer 2

The reaction releases 400 kJ of heat.

Step-by-step explanation:

Hello,

In this case, the meaning of such -400 kJ in a reaction aims to the released energy once the chemical reaction goes to completion, it means that -400 kJ are realsed in form of heat, therefore, the products have 400 kJ less energy than the rectants, considering the attached picture.

Best regards.