SSC CHSL 2025 PYQ — Question 86

The correct answer is Option 1: Solidification.
Explanation:
At atmospheric pressure, the transformation of a substance from the liquid state to the solid state is called 'Freezing' or 'Solidification.' This process occurs when the temperature of the liquid drops to its Freezing Point, causing the kinetic energy of its molecules to decrease and leading them to arrange themselves into a fixed solid structure. For example, the conversion of water into ice.
Additional Facts:

• Other important terms related to changes in the states of matter:
• Deposition: When a substance changes directly from the gaseous state to the solid state (e.g., the formation of frost).
• Sublimation: When a solid substance changes directly into a gas without passing through the liquid state (e.g., camphor or iodine).
• Vaporization: The transformation of the liquid state into the gaseous state.
• Melting (or Fusion): The transformation of the solid state into the liquid state.
• Condensation: The transformation of the gaseous state into the liquid state.

Potential Questions for Upcoming Exams:
Question: What is the temperature at which a solid substance begins to change into a liquid called?
Answer: Melting Point.
Question: When camphor is heated, it changes directly into a gas; what is this process called?
Answer: Sublimation.
Question: What is Dry Ice actually?
Answer: Solid Carbon Dioxide (CO₂).