Enthalpy of combustion of carbon to `CO_(2)` is `-393.5 kJ mol^(-1)`. Calculate the heat released upon formation of `35.2 g` of `CO_(2)` from carbon and dioxygen gas.

Answer

`-314.8 kJ `

Explanation

Formation of `CO_(2)` from carbon and dioxygen gas can be represented as :
`C_((s))+O_(2(s))rarrCO_(2(s))" " Delta_(f)H=-393.5 kJ "mol"^(-1)` (1 mole =44 g)
Heat released on formation of 44 g `CO_(2)=-393.5 kJ :mol"^(-1)`
`:.` Heat released on formation of `35.2 g CO_(2)`
`= (393.5 kJ "mol"^(-1))/(44g)xx35.2g`
`=-314.8 kJ "mol"^(-1)`