Answer:
Reaction is endothermic
Explanation:
The given reaction is :
A + B → C + D
The enthalpy change of a reaction (ΔH) is given by the difference between the enthalpy of the products and that of the reactants.
ΔH = H(products) - H(reactants) ------(1)
Now, enthalpy is a form of chemical energy which is essentially a measure of the heat content of the system. It is given that:
Chemical energy of reactants (A+B) = 248 kJ
Chemical energy of products (C+D) = 841 kJ
Based on equation (1) we have:
ΔH = H(C+D) - H(A+B) = 841-248 = +593 kJ
Since, the enthalpy change is positive, this implies that the reaction is endothermic i.e. energy is absorbed or required to carry out the reaction.