Which of the following summarizes a change that takes place as a solid turn to a liquid?
A.
Particles have a decrease in mobility.
B.
Particles become less ordered.
C.
Intermolecular forces between particles become stronger.
D.
Particles move closer together.
The correct answer and Explanation is :
The correct answer is B. Particles become less ordered.
Explanation:
When a solid turns into a liquid, the process is called melting, and it involves a fundamental change in the arrangement and movement of particles.
In a solid, the particles (atoms, molecules, or ions) are arranged in a highly ordered structure, typically in a lattice. These particles vibrate around fixed positions but are held together by strong intermolecular forces, which prevent them from moving freely.
As heat is applied to the solid, the particles gain kinetic energy. When the temperature reaches the melting point, the energy supplied is enough to overcome some of the intermolecular forces holding the particles in place. The particles start to break free from their fixed positions and move past one another. As a result, the highly ordered structure of the solid breaks down, and the particles become less ordered, forming a liquid.
In the liquid state, particles have more freedom to move, though they are still close together. However, unlike in a solid, they are not arranged in a regular, repeating pattern. They can move around each other, which gives the liquid its ability to flow and take the shape of its container. Despite this increased mobility, the intermolecular forces in a liquid are still strong enough to keep the particles relatively close together, preventing them from completely dispersing like in a gas.
Why the Other Options Are Incorrect:
- A. Decrease in mobility: This is incorrect because the mobility of particles actually increases as a solid turns into a liquid.
- C. Stronger intermolecular forces: This is incorrect because intermolecular forces become weaker, allowing particles to move more freely.
- D. Particles move closer together: This is incorrect because the particles in a liquid are usually slightly farther apart than in a solid.
Thus, the process of melting is characterized by an increase in particle motion and a decrease in order.