Question

Describe how the state of matter changes in terms of the movement of tiny particles.

Answer 1

Interconversion of solid into a liquid

• On increasing the temperature of solids, the kinetic energy (K.E.) of particles increases.
• Due to an increase in K.E., the particles start vibrating with greater speed.
• The energy supplied by heat overcomes the force of attraction between the particles. Then, the particles leave their fixed positions and start moving freely, and thus solid melts.

Interconversion of liquid into the gaseous state

• When heat is supplied to water, particles start moving faster.
• At a certain temperature, a point is reached when the particles have enough energy to break the forces of attraction between the particles.
• At this temperature, the liquid starts changing into gas.