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COMEDK2022ChemistryThermodynamics (C)

In which of the following changes, entropy decreases?

Options

  1. ARusting of iron
  2. BMelting of ice
  3. CVaporisation of camphor
  4. DCrystallisation of sucrose from solution

Correct answer

D. Crystallisation of sucrose from solution

Step-by-step solution

Entropy is a measure of the randomness or disorder of a system. A decrease in entropy corresponds to a transition from a more disordered state to a more ordered state. Rusting of iron involves the reaction of iron with oxygen and water to form hydrated iron(III) oxide. This process increases the number of particles and the complexity of the system, leading to an increase in entropy. Melting of ice is a phase transition from solid to liquid. The liquid state has higher molecular mobility and disorder than the solid

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