The heating curve for a substance is shown below.The substance initially is a solid.It then becomes a liquid and a gas.Which of the line segments (I-V)represents the solid to liquid phase transition?

Question

Quizplus · Accepted Answer

Line segment II represents the solid to liquid phase transition. This is because during this segment, the substance is increasing in temperature while remaining in the solid phase until it reaches its melting point. Once it reaches its melting point, it begins to absorb heat but remains at the same temperature until all the solid has melted, indicating the phase transition from solid to liquid.

The Heating Curve for a Substance Is Shown Below