Question

cl-cl 242
h-h 435
hydrogen and chlorine gases react to produce hydrochloric acid according to the reaction.
h₂ + cl₂ → 2hcl
how much total bond energy, in kj/mol, is in the products of the reaction?
(1 point)
854
677
427
435

Explanation:

Step1: Identify number of H - Cl bonds

The product is 2HCl, so there are 2 H - Cl bonds.

Step2: Use bond - energy value

The bond energy of H - Cl is not given directly, but we are interested in the total bond energy of products. The total bond energy of products is calculated based on the number of bonds in the products. For 2 moles of HCl, if we assume the bond energy of one H - Cl bond is considered (and we know from the reaction stoichiometry), the total bond energy of products is calculated as follows.
The reaction produces 2 moles of HCl. The bond - energy of H - Cl is not given separately here, but we calculate the total bond energy of products using the fact that for the reaction $H_2+Cl_2
ightarrow2HCl$, the total bond energy of products is the sum of the bond energies of the H - Cl bonds in the 2 moles of HCl.
The bond - energy of H - Cl is approximately 431 kJ/mol. The total bond energy of 2 moles of HCl is $2\times431 = 862$ kJ/mol. However, if we assume we are using the values in a different context and calculate based on the idea of bond - making in the products:
The reaction produces 2 moles of HCl. Each HCl has one H - Cl bond.
The total bond energy of products = $2\times427=854$ kJ/mol (assuming a bond - energy value of 427 kJ/mol for H - Cl for the sake of this problem with the given options).

Answer:

854