Question

Changing from solid to a liquid at or above melting point is _____________.

liquefaction

solidification

vaporization

boiling

Answer 1

Changing from solid to a liquid at the melting point is called liquefaction or melting, while solidification, vaporization, and boiling refer to other phase changes.

Step-by-step explanation:

Changing from solid to a liquid at or above the melting point is known as liquefaction. This process is also commonly referred to as melting. The melting point is the temperature at which the solid and liquid phases of a substance are in equilibrium. In contrast, solidification is the process of a liquid becoming a solid, vaporization (or boiling) is the transition from a liquid to a gas, and boiling is the process that occurs at the boiling point when a liquid turns into a gas.

The melting point is a fundamental physical property and allows us to predict the state of matter of a substance at a given temperature. Understanding these phase changes is crucial for various applications in science and engineering where the physical state of materials matters significantly.

Answer 2

Changing from solid to a liquid at or above the melting point is liquefaction, and the option that best represents this process is: A: liquefaction.

When a solid substance reaches its melting point, it undergoes a phase transition and changes into a liquid state. This process is commonly referred to as melting. The particles in a solid have a fixed arrangement and vibrate in a fixed position. However, as heat is applied, the particles gain energy and their vibrations become more vigorous. At the melting point, the energy provided is sufficient to overcome the forces holding the particles together, causing them to break free from their fixed positions and slide past each other, resulting in a change of state from solid to liquid.

Option B, solidification, refers to the reverse process when a liquid changes into a solid by losing heat and cooling below its freezing point.

Option C, vaporization, is the process in which a liquid changes into a gas. This occurs at or above the boiling point of the substance.

Option D, boiling, specifically refers to the rapid vaporization that occurs throughout the liquid when it reaches its boiling point.

Changing from solid to a liquid at or above the melting point is called melting. The process involves particles gaining energy and breaking free from their fixed positions, resulting in a transition from a solid to a liquid state.

Therefore, the correct option is A: liquefaction.