However, the energy change of a reaction can be negative if it is exothermic. Energy change = how much energy is absorbed to break the bonds of the reactants — the amount of energy when the bonds of the products are made. So, if more energy is released than absorbed, then the energy change is negative.
For example, N2 + 3H2 —> 2NH3. This is a reversible reaction, meaning that the products are broken down into the reactants at the same rate that the products is made. Anyway, the forward reaction (making NH3) is exothermic; the energy change is negative as more energy is given out when bonds are made. However, the reverse reaction (making N2 and H2) is endothermic; the energy change is positive as more energy is absorbed to break bonds.
I hope this helps and that it’s clear as I’m typing this out on my phone
by increasing temperature the rate constant or rate of a reaction decreases....in that case they said activation energy is low....then I am not understanding it...can u please explain it.