Question 30

Particles within a substance vibrate around fixed positions in a solid state of matter.

In solids, particles are closely packed together and can only vibrate in place, maintaining fixed positions relative to each other. This restricted movement gives solids their definite shape and volume.

A) Plasma

Plasma is a state of matter where particles are highly energized and move freely, resulting in an ionized gas-like state. In this state, particles do not vibrate around fixed positions, making this option incorrect.

B) Liquid

In liquids, particles are close together but can move past one another, allowing liquids to flow and take the shape of their container. This movement means that particles do not vibrate around fixed positions, thus making this option incorrect.

C) Gas

In gases, particles are far apart and move independently at high speeds. They do not vibrate around fixed positions; rather, they fill the available space. Therefore, this option is also incorrect.

D) Solid

In solids, particles are tightly packed and can only vibrate around fixed positions, which is the defining characteristic of this state of matter. This option correctly describes the behavior of particles in solids.

Conclusion

The correct answer is D because it accurately describes the vibrational motion of particles in solids, where they maintain fixed positions. Options A, B, and C do not fit this description, as they pertain to states of matter where particle movement differs significantly from the fixed vibrational motion characteristic of solids.