MCQ
Whether a reaction is endothermic or exothermic can be indicated by:
  • A
    Enthalpy change.
  • B
    Entropy change.
  • C
    Activation energy.
  • D
    Specific heat capacity.

Answer

  1. Enthalpy change.

Explanation:

Whether a reaction is endothermic or exothermic can be indicated by enthalpy change.

Enthalpy change is the difference in the enthalpy of products and the enthalpy of reactants.

A positive value of enthalpy change indicates endothermic reaction as the enthalpy of products is more than the enthalpy of reactants.

A negative value of enthalpy change indicates exothermic reaction as the enthalpy of products is less than the enthalpy of reactants.

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