The hydrocarbons cyclohexane (C6H12), ΔHf° = -156 kJ/mol, and 1-hexene (C6H12), ΔHf° = -74 kJ/mol, have the same empirical formula. (a) Calculate the standard enthalpy change for the transformation of cyclohexane to 1-hexene. (b) Which has greater enthalpy, cyclohexane or 1-hexene?

Verified step by step guidance

Step 1: Understand the problem by identifying the given data: Cyclohexane (C6H12) has a standard enthalpy of formation (ΔHf°) of -156 kJ/mol, and 1-hexene (C6H12) has a ΔHf° of -74 kJ/mol.

Step 2: To find the standard enthalpy change (ΔH°) for the transformation of cyclohexane to 1-hexene, use the formula: ΔH° = ΔHf°(products) - ΔHf°(reactants).

Step 3: Substitute the given values into the formula: ΔH° = (-74 kJ/mol) - (-156 kJ/mol).

Step 4: Simplify the expression by subtracting the enthalpy of formation of cyclohexane from that of 1-hexene.

Step 5: To determine which compound has greater enthalpy, compare the ΔHf° values: the compound with the less negative (or more positive) ΔHf° has greater enthalpy.

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