Question

The enthalpy of atomisation for the reaction `CH_(4) (g) rarr C (g) + 4H (g) " is " 1665 kJ mol^(-1)`. What is the bond energy of `C - H` bond ?

Answer 1

In `CH_(4)`, there are four `C - H` bonds. The enthalpy of atomisation of 1 mole of `CH_(4)` means dissociation of four moles of `C - H`bonds.
`:. C - H` bond energy per mol `= (1665 kJ)/(4 mol)`
`= 416.25 kJ mol^(-1)`