P6: Molecules And Matter

Question 1

Which state of matter is the least energetic? And why?

Answer 1

Soilds because they are held together in fixed positions

Question 2

When a substance changes state, what happens to its mass?

Answer 2

It stays the same because the number of particles stays the same

Question 3

What happens to a substance when the temperature is increased?

Answer 3

The particles move faster

Question 4

What is the change of state of a solid to a liquid?

Answer 4

Melting

Question 5

What is the change of state of a liquid to a gas?

Answer 5

Evaporation

Question 6

What is the change of state of a liquid to a solid?

Answer 6

Freezing

Question 7

What is the change of state of a gas to a liquid?

Answer 7

Condensing

Question 8

What is the change of state of a soild to a gas?

Answer 8

Sublimation

Question 9

What is the change of state of a gas to a soild?

Answer 9

Desublimation

Question 10

Why is the densiry of a gas much less than a solid or a liquid?

Answer 10

The particles of a substance in its gas state move about at random much faster than they do in a liquid. On average, they are much further apart than the particles than a liquid. Therefore, the density of a gas is much less than the density of a liquid