In presence of a catalyst the heat evolved or absorbed during a reaction-

In the presence of a catalyst, the heat evolved or absorbed during a reaction remains unaffected.

Here's why:

• A catalyst works by providing an alternative reaction pathway with a lower activation energy. This lower activation energy allows the reaction to proceed faster, but it doesn't change the overall energy difference between the reactants and products.
• The heat evolved or absorbed during a reaction (enthalpy change, ΔH) is the difference between the potential energy of the reactants and the potential energy of the products. This difference remains constant regardless of the reaction pathway.