In which of the following reactions, the enthalpy is the least ?

For which of the following reaction, change of enthalpy equals the change in internal energy ?

Which of the following has least bond enthalpy ?

Some reactions are given which of the following reaction refers enthalpy of hydration.

For which one of the following reaction does not the enthalpy change of a reaction corresponds to Lattice energy of KBr ?

Heat of which of the following reaction gives enthalpy of formation directly?

Heat of which of the following reaction gives enthalpy of formation directly?

Enthalpy of which of the following reactions does not represent the standard enthalpy of formation?