Using the data provided, calculate the multiple bond energy ( kJ mol ⁻¹ ) of a C C bond in C ₂ H ₂ . That energy is (take the bond energy of a C - H bond as 350 ~kJ ~mol ⁻¹ ) 2 C ( s )+ H ₂( ~g ) HC = CH ( g ) ; H =225 ~kJ ~mol ⁻¹2 C ( s ) 2 C ( g ) ; H =1410 ~kJ ~mol ⁻¹ H ₂( ~g ) 2 H ( g ) ; H =330 ~kJ ~mol ⁻¹

Step-by-step solution

(i) 2 C ( s )+ H ₂( ~g ) H - C C - H ( g ) H =225 ~kJ ~mol ⁻¹ (ii) 2 C ( s ) 2 C ( g ) H =1410 ~kJ ~mol ⁻¹ (iii) H ₂ (g) 2 H (g) H =330 ~kJ ~mol ⁻¹ From equation (i) : array l 225= [2 H _ C ( s ) C ( g ) +1 BE _ H - H ] - [2 BE _ C - H +1 BE _ C C ] 225=[1410+1 330]- [2 350+1 BE _ C C ] 225=[1410+330]- [700+ BE _ C C ] 225=1740-700- BE _ C C BE _ C C =815 ~kJ ~mol ⁻¹ array