Given that Δ Hf( H )=218 kJ / mol, express the H - H bond energy in kcal / mol.

Question

Given that Δ Hf( H )=218 kJ / mol, express the H - H bond energy in kcal / mol. (A) 52.15 (B) 911 (C) 104 (D) 52153

Tardigrade Admin · Accepted Answer

Given: Given: Δ H f( H )=218 kJ / mol i.e., (1/2) H2 arrow H: Δ H=218 kJ / mol or H2 arrow 2 H: Δ H=436 kJ / mol =(436/4.18)=104.3 kcal / mol Thus, 104.3 kcal/mol energy is absorbed for breaking one mole of H - H bonds. Hence, H-H bond energy is 104.3 kcal / mol.

Q. Given that ΔHf​(H)=218kJ/mol, express the H−H bond energy in kcal/mol.

52.15

911

104

52153

Given : Given : ΔHf(H)=218kJ/mol i.e., 21​H2​→H:ΔH=218kJ/mol or H2​→2H:ΔH=436kJ/mol =4.18436​=104.3kcal/mol Thus, 104.3kcal/mol energy is absorbed for breaking one mole of H−H bonds. Hence, H−H bond energy is 104.3kcal/mol.

Q. Given that $Δ H_{f} (H) = 218 k J / m o l$ , express the $H - H$ bond energy in $k c a l / m o l$ .