Molar heat of vaporization is the amount of heat required to convert one mole of:
Correct answer: A. A liquid into its vapours at its boiling point
- A. A liquid into its vapours at its boiling point
- B. Liquids into its vapours
- C. Solids into vapours
- D. Solid into liquid at its melting point
Explanation
Molar heat of vapourization refers to the conversion of one mole of a liquid to its vapors at a constant temperature, which is the boiling point of the liquid. That is why option A is correct.Option B is partially correct because vaporization refers to the conversion of a liquid to gas, however, at a constant temperature. Options C and D are incorrect because vaporization does not involve the conversion of solids to liquids.
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About Thermochemistry and Energetics of Chemical Reactions
Thermochemistry measures energy changes in chemical reactions and distinguishes exothermic from endothermic processes. Work covers systems, surroundings and state functions, internal energy, the first law of thermodynamics, enthalpy and Hess's law, including the sign conventions used when heat enters or leaves a system.
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