If the combustion of 1 g of graph produces 20.7 kJ of heat, what will be molar enthalpy change ? Give the significance of sign also.

If the combustion of 1 g of graph produces 20.7 kJ of heat, what will

1.	If the combustion of 1 g of graph produces 20.7 kJ of heat, what will be molar enthalpy change ? Give the significance of sign also.
Answer» Solution :GIVEN that, ENTHALPY of combustion of 1 g graphite = 20.7 kJ Molar enthalpy CHANGE for the combustion of graphite, `Delta H =` enthalpy of combustion of 1 g graphite `XX` molar mass `Delta H = - 207 kJg^(-1)xx 12 g MOL^(-1)` `Delta H = - 2.48 xx 10^(2) kJ mol^(-1)` Negativve sign in the value of `Delta H` indicates that the reaction is exothermic.