Question

Diketahui energi ikatan rata rata:
C-C =347 C-H=413
C=C =612 C=_ =835(garis- ada 3)
C-Cl =346 H-C =432
perubahan entalpi reaksi propuna dengan gas HCl menjadi 2,2-dikloropropana adalah

Answer 1

CH ≡ C - CH3 + 2 HCl → CH3 - C (Cl) (Cl) - CH3

ΔH = ∑D reaktan - ∑D produk
     = [(4 C-H + C≡C + 2 C-C + 2 H-Cl)] - [(6 C-H + 2 C-C + 2 C-Cl)]
     = [(C≡C + 2 H-Cl)] - [(2 C-H  + 2 C-Cl)]
     = [(835 + (2 × 432)] - [((2 × 413) + (2 × 346)]
     = 181 kJ