Question

A tube holds a monatomic substance with equal amounts of liquid and gas at equilibrium. A student analyses the problem and says, “According to the Particle Model, the liquid phase has more thermal energy than the gas phase.” Another student digests this and then states, “This is incongruent with the Three Phase Model, which states that a gas has more energy than a liquid.”

Which of the statements is/are true? Which is/are false? Why?

Answer 1

As there are equal amounts of gas and liquid inside the tube, so the number of atoms are also equal of liquid in GAS FORM or LIQUID FORM.

Energy per atom is hgher for a particle in motion. As gaseous state particles are moving more vigorously as compared to liquid phase particles, so the second student's is correct.

Particle theory og matter has following features:

1. Particle in solids is in rigit contact with each other and have fixed shape.

2. Particles of Gases are in constant motion with almost no interaction in between them. Collisons are elastic.

3. Particles of fluid are touching each other but can chage their shape and takes shape of vessel.

4. Due to temperature particle gains vibrationsal kinetic energy. The more the anount of heat, more is the vibration,

5. Due to gaining of Vibrational energy a solid melts, and then evaporates. That is chages its phase.