MDCAT Chemistry MCQ #503

What is the enthalpy change for the reaction of 1 mole of benzaldehyde with 1 mole of methanol to form benzaldehyde dimethyl acetal, given that the enthalpy of formation of the acetal is -50 kJ/mol and the enthalpy of formation of the aldehyde is -20 kJ/mol?

MDCAT Chemistry MCQ #503

  1. Question 1

    Q1. What is the enthalpy change for the reaction of 1 mole of benzaldehyde with 1 mole of methanol to form benzaldehyde dimethyl acetal, given that the enthalpy of formation of the acetal is -50 kJ/mol and the enthalpy of formation of the aldehyde is -20 kJ/mol?

    • A) -30 kJ/mol
    • B) -40 kJ/mol
    • C) -50 kJ/mol
    • D) -60 kJ/mol

    Answer: -40 kJ/mol

    Explanation: Enthalpy change is calculated from enthalpies of formation of reactants and products.