Question

The answer is A I dont understand how. I see 4 hydrogen bonds, 1 triple C bond in the reactants and 6 c-h bonds, and one c-c bond in the products. But I am wrong. pLEASE help with a detailed explanation

1 weakest? culpole-alpole D) ion-dipole E) hydrogen bonding 11. What is the enthalpy change of the following reaction? Creactens H-C C - H + 2 H -H. Average bond energies (kJ/mol) CC single 345 CC double CH 415 HH 615 435 CC triple 835 A) -300 kJ B)-310 kJ C) -50 kJ D) +345 kJ E) +310 kJ 61415) + 615

Answer 1

Equation: CH (8) + 2H2(g) →→ CH (8) Bond energy of C=C bond = 835 kJ/mol Bond energy of C-Cbond = 345 kJ/ mol Bond energy of C-H bond = 415 kJ/mol Bond energy of H-H bond = 435 kJ/mol Number of bonds present in the reactants: 2 C-H,1C-C, and 2 H-H Number of bonds present in the reactants 6 C-H and 1C-C Enthalpy change of the reaction, AHD = Bond energy of rectants – Bond energy of products = [(2(C-H)+1(C=C)+2(H-H))-(6(C-H)+1(C-c))] [[2(415 kJ)+1(835kJ)][6(415 kJ) 11 LL +2(435 kJ)] | +1(345 kJ)]] = - 300 kJ