Bond Energy Practice – 16-Problem Chemistry Set

Students will calculate the enthalpy of reaction (Hrxn) using the bond-energy method: bonds broken minus bonds formed.

Students will apply standard bond-energy values (e.g., C-H, O=O, N-H) to balanced chemical equations.

Students will determine molecular structure from a chemical formula or equation in order to count the bonds broken and formed.

Have students complete the six diagram-based problems first, since the bonds are already identified, before moving to the ten equation-only problems that require structuring the molecule themselves.

Review the worked answer key's substitution step (e.g., 'Hrxn = H-H + O=O − 4(O-H)') with students before they check final answers, since most calculation errors happen at the bond-counting stage rather than the arithmetic.

Since the file is an editable Word document, remove or swap individual reactions to shorten the set or match a specific unit.

Bond-energy calculation — applying Hrxn = bonds broken − bonds formed to balanced chemical equations.

Molecular structure analysis — identifying and counting bond types (single, double, triple) in reactants and products.

Quantitative problem solving — substituting tabulated bond-energy values (kJ/mol) and completing multi-step arithmetic to reach a signed final answer.