The reaction which shows heat of formation of water correctly is

The reaction which shows standard heat of formation of water correctly is

The heat of formation of water is given by :

In which of the following reaction does the heat change represent the heat of formation of water ?

In which one of the following reactions does the heat change represent the heat of formation of water?

Given the following standard heats of reactions: (a) heat of formation of water = -68.3 kcal , (b) heat of combustion of C_(2)H_(2) =- 310.6 kcal , (c ) heat of combustion of ethylene =- 337.2 kcal . Calculate the heat of reaction for the hydrogenation of acetylene at constant volume and at 25^(@)C .

Given the following standard heats of reactions: (a) heat of formation of water = -68.3 kcal , (b) heat of combustion of C_(2)H_(2) =- 310.6 kcal , (c ) heat of combustion of ethylene =- 337.2 kcal . Calculate the heat of reaction for the hydrogenation of acetylene at constant volume and at 25^(@)C .