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MHT CET202617 April 2026Evening ShiftChemistryThermodynamics (C)Actual

Which of the following processes is an endothermic ?

Options

  1. AThe aqueous NaOH and HCl solutions mixed together.
  2. BFormation of ammonia by Haber process.
  3. CIce melts at room temperature.
  4. DThe freezing of liquid water.

Correct answer

C. Ice melts at room temperature.

Step-by-step solution

Mixing of aqueous NaOH and HCl is a neutralization reaction, which is highly exothermic. Formation of ammonia by the Haber process is an exothermic reaction as heat is released. Melting of ice requires the absorption of heat from the surroundings to overcome the intermolecular forces of attraction between water molecules. Thus, it is an endothermic process. Freezing of liquid water releases heat to the surroundings, making it an exothermic process. Answer: Ice melts at room temperature.

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