If the combustion of1g of graphite produces 20.7 kJ of heat, whatwill be molar enthalpy change ? Give the significance of sign also.

If the combustion of1g of graphite produces 20.7 kJ of heat, whatwill

1.	If the combustion of1g of graphite produces 20.7 kJ of heat, whatwill be molar enthalpy change ? Give the significance of sign also.
Answer» Solution :Molar enthalpy CHANGE of combustion of graphite `=` Enthalpy of combustion of 1 g `xx` Molar mass `= 20.7 kJ MOL^(-1) xx 12 g mol^(-1)` i.e., `DeltaH = - 2.48 xx 10^(2)kJ mol^(-1)` Negative value of `DeltaH` shows that the reaction is exothermic .