The enthalpies of combustion of 'CH_4' and 'C_6 H_6' are '-890.3' and '-1559.7 kJmol^(-1)' respectively. Which of the two has greater efficiency of fuel per gram 2 .

The enthalpies of combustion of S, SO_(2) and H_(2) are -298.2, -98.7 and -287.3.kJ mol^(-1) respectively. If enthalpy of the reaction SO _(x (g)) + H _(2) O _((f)) to H _(2 ) SO _(4 (f)) is - 130.2 kJ mol ^(-1), the enthalpy of formation of H_(2)SO_(4) is

If the dissociation energies of 'CH_4' and 'C_2 H_6' are 360 and '620 kcal/ mol' respectively, then the bond energy of 'C -C' bond is

Critical temperature for CO_2 and CH_4 are 30.98^@C and -81.9^@C respectively. Which of these has stronger intermolecular forces. Why?

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)).

Delta H_("combustion") of C _(6) H _(6) (l) . C(s) and H _(2) (g) are - 3000 kJ ,-390KJ mol^(-1) and - 290 kJ mol ^(-1) respectively. Hence heat of formation of benzene, is

The standard enthalpies of formation of H_(2)O(l) and CO_(2)(g) are respectively -286" kJ mol"^(-1) and -394" kJ mol"^(-1) . If the standard heat of combustion of CH_(4)(g)" is "-891" kJ mol"^(-1) , then the standard enthalpy of formation of CH_(4)(g) is