Zaymiey

⚛️ Physics  ·  Thermal Properties of Matter  ·  NEET & JEE

Steam at 100°C is passed into water to raise its temperature. The large heat released by steam is mainly due to:

Answer: Latent heat of vaporization released during condensation.

  • A The unusually high specific heat capacity of steam compared to water
  • B Latent heat of vaporization released during condensation
  • C The high temperature of the steam by itself, with no phase change
  • D The relatively low density of steam compared to liquid water

Correct answer: B. Latent heat of vaporization released during condensation

Explanation: When steam condenses to water at 100°C, it releases a large amount of latent heat of vaporization (2256 kJ/kg), which is much greater than what sensible heat alone would provide.

Heating Curve: Ice → Water → SteamHeat added (Q)T (°C)ice warms (-ve→0°C)melting (0°C, latent heat)water warms (0→100°C)boiling (100°C, latent heat)FLAT regions = phase change (all heat goes into breaking bonds, NOT raising temperature)

During a phase change (melting or boiling), temperature stays constant while heat is absorbed entirely as latent heat (Q=mL); temperature only rises again once the substance is fully in its new phase.

Concept context

Temperature scales, thermal expansion, calorimetry, and the three modes of heat transfer including radiation laws.

Read the full Thermal Properties of Matter notes →