Question

Which of the following assumptions is/are true according to kinetic theory?

• A. All matter is composed of small particles
• B. The particles of matter are in constant motion
• C. All collisions between the particles of matter are perfectly elastic
• D. All of the above

Answer 1

The correct option is D All of the above

The kinetic theory explains the differences between the three states of matter. It states that all matter is made up of moving particles which are molecules or atoms. In solids, the particles are so tightly bound to each other that they can only vibrate but not move to another location. In liquids, the particles have enough free space to move about, but they still attract one another. In gases, the particles are far apart and can move about freely since there is much free space. Solids change into liquids, and liquids into gases when the particles gain more kinetic energy, like when being heated and are able to move apart from one another. When the molecules vibrate more quickly upon heating, some of them escape from the matter.
So, the kinetic theory states that:

1. All matter is composed of small particles.

2. The particles of matter are in constant motion.

3. All collisions between the particles of matter are perfectly elastic.