Bond dissociation enthalpy of `H_(2)` , `Cl_(2)` and `HCl` are `434, 242` and `431KJmol^(-1)` respectively. Enthalpy of formation of `HCl` isA. `93 kJ mol^(-1)`B. `-245 kJ mol^(-1)`C. `-93 kJ mol^(-1)`D. `+245 kJ mol^(-1)`

Bond dissociation enthalpy of `H_(2)` , `Cl_(2)` and `HCl` are `434, 2

1.	Bond dissociation enthalpy of `H_(2)` , `Cl_(2)` and `HCl` are `434, 242` and `431KJmol^(-1)` respectively. Enthalpy of formation of `HCl` isA. `93 kJ mol^(-1)`B. `-245 kJ mol^(-1)`C. `-93 kJ mol^(-1)`D. `+245 kJ mol^(-1)`
Answer» Correct Answer - C `(1)/(2)H_(2)(g)+(1)/(2)Cl_(2)(g)toHCl(g)`, `DeltaH^(@)=?` `Delta_(r )H^(@)=(1)/(2)BE(H_(2))+(1)/(2)BE(Cl_(2))-BE(HCl)` `=(1)(2)(434)+(1)/(2)(242)-431` `=217+121-431=-93 kJ mol^(-1)`

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Bond dissociation enthalpy of `H_(2)` , `Cl_(2)` and `HCl` are `434, 242` and `431KJmol^(-1)` respectively. Enthalpy of formation of `HCl` isA. `93 kJ mol^(-1)`B. `-245 kJ mol^(-1)`C. `-93 kJ mol^(-1)`D. `+245 kJ mol^(-1)`

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