Calculate `DeltaH_r^theta` for reaction `H_2(g)+Br_2(g)rarr2HBr(g)` given that the bond energies of H-H, Br-Br and H-Br are 435, 192 and 364 kJ`mol^-1` respectively.

Calculate free energy change at 27^(@)C for the reaction H _(2) + Cl _(2) to 2 HCl Given bond enthalpies of H_(2), Cl_(2) and HCl are 435, 240 and 430 kJ mol^(-1) respectively and entropies of H_(2), Cl_(2) and HCl are 131,223 and 187 JK^(-1) respectively

Calculate the standard enthalpy change for the reaction CH_4(g) +2O_2(g) rarr CO_2(g)+2H_2O(l) Given that the standard enthalpies of formation of CH_4(g),CO_2(g), and H_2O(l) are -74.8 kJ mol^-1, -393.5 kJ mol^-1 and -285.8 kJ mol^-1 respectively.

Assertion :The molecularity of the reaction H_(2) + Br_(2) rarr 2 HBr is 2. Reason: The order of the reaction is 3/2.

a) The enthalpy of combustion of CH_(4(g)), C_(graphite) and H_(2(g)) at 298 K are - 890.3 kJ mol^-1 , - 393.5 kJ mol^-1 and -285.8 kJ mol^-1 respectively. Calculate the enthalpy of formation of CH_(4(g)).

For the reaction N_{2}(g) + 3H_{2}(g)rarr2NH_{3}(g) , how are the rate of reaction expressions -d[H_{2}]/dt and d[NH_{3}]/dt interrelated?