Answer:
option d= -440 kj
Explanation:
chemical equation:
CH4 + 4Cl2 → CCl4 + 4HCl
Given data:
Bond broken energies:
C-H = 413 Kj/mol
Cl-Cl =243 Kj/mol
Bond formation energies:
C-Cl = 339 Kj/mol
H-Cl = 427 Kj/mol
Formula:
δh° = ∑n (bonds broken) - ∑m (bonds formation)
Solution:
Total bonds broken energy:
C-H = 413 Kj/mol 4×413 Kj/mol = 1652 Kj/mol
Cl-Cl = 243 Kj/mol 4×243 Kj/mol = 272Kj/mol
total = 2624 Kj/mol
Total bond formation energy:
C-Cl = 339 Kj/mol 4×339 Kj/mol = 1356 Kj/mol
H-Cl = 427 Kj/mol 4×427 Kj/mol = 1708 Kj/mol
total = 3064 Kj/mol
Now we will put the values in formula to calculate the δh° for reaction.
δh° = ∑n (bonds broken) - ∑m (bonds formation)
δh° = (2624) - (3064)
δh° = -440 kj