In the balanced combustion reaction of nitric oxide (2 NO + O_2 → 2 NO_2), how many chemical bonds are broken in the reactants per mole of reaction?

• A. 3 bonds
• B. 5 bonds
• C. 2 bonds
• D. 4 bonds

Answer: (A)

Verified step by step guidance

1. Write down the balanced chemical equation: \$2\ NO + O_2 \rightarrow 2\ NO_2$.
2. Identify the bonds present in the reactants. For nitric oxide (NO), there is one N=O bond per molecule, and for oxygen (O_2), there is one O=O double bond per molecule.
3. Calculate the total number of bonds broken per mole of reaction by considering the stoichiometric coefficients: 2 moles of NO and 1 mole of O_2.
4. Multiply the number of bonds in each molecule by the number of moles reacting: for NO, 2 molecules × 1 N=O bond each = 2 bonds; for O_2, 1 molecule × 1 O=O bond = 1 bond.
5. Add the bonds broken from all reactants to find the total bonds broken per mole of reaction: 2 (from NO) + 1 (from O_2) = 3 bonds.