Sample Questions on Melting Point

Question 1: What causes phase change?

Answer:

When the temperature or pressure change of a system occurs, the phase changes. Upon increasing the temperature or pressure of the system, the intramolecular forces of attraction increase. Upon decreasing the temperature, the molecules or atoms turn into a rigid structure.

Question 2: Does temperature change during the process of heating ice?

Answer:

As we constantly supply heat energy to transform ice into water, the temperature of the system doesn’t change. The heat energy is absorbed by the ice changing slowing into the liquid state. Both the states of matter coexist together during this process.

Question 3: How does melting occur in the case of amorphous solids?

Answer:

The non-crystalline solids, such as glass or pitch undergo melting by slowly decreasing viscosity with the simultaneous increase in the temperature. However, there is no sharp transformation from solid to liquid state.

Question 4: Define the heat of fusion.

Answer:

The amount of energy required by a pure substance to change from the solid to a liquid state is termed as the enthalpy of fusion (or heat of fusion) of the substance. It is denoted by ΔH_fus.

Question 5: Differentiate between boiling and melting.

Answer:

Boiling is the process of melting of liquid to gas state whereas melting is the transformation of solid to liquid state.

Question 6: How does energy change occur during melting?

Answer:

Heat must be supplied to the enclosed system in order to simulate the melting of the substance. When energy is supplied the atoms composing the substance break away and are pulled apart farther.

Melting point is the temperature at which any solid changes its form from solid to liquid. The melting point of any solid is the temperature at which it changes its temperature from solid to liquid at constant pressure, (generally at constant pressure). At the melting point, the liquid and solid phases of any material exist simultaneously.

In this article, we will learn about melting points and various factors that affect melting points, examples, and others in detail.