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MDCAT
Chemistry
2021

Chemistry · Thermochemistry

Work through this past-paper style MCQ, then read the full explanation. Practice more chemistry questions on mMCQ with adaptive drills and topic analytics.

Question

Law of conservation of energy is actually:

Options
  • A

    Second law of thermodynamics

  • B

    Third law of thermodynamics

  • C

    First law of thermodynamics

  • D

    Zeroth law of thermodynamics

Explanation

The correct answer is the First Law of Thermodynamics, which directly restates the Law of Conservation of Energy. It asserts that energy within a closed system remains constant, though it may change forms. The other options are incorrect as they relate to different aspects of thermodynamic processes: the Second Law addresses entropy, the Third Law pertains to absolute zero conditions, and the Zeroth Law deals with thermal equilibrium.

The Second Law of Thermodynamics deals with the direction of energy transfer and the increase of entropy, not the conservation of energy.

The Third Law of Thermodynamics concerns the behavior of systems as they approach absolute zero, not the conservation of energy.

The First Law of Thermodynamics is synonymous with the Law of Conservation of Energy, stating that energy cannot be created or destroyed, only transformed or transferred. This makes it the correct answer.

The Zeroth Law of Thermodynamics defines thermal equilibrium and is unrelated to the conservation of energy.

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Tagged under Chemistry · Thermochemistry · 2021