P3

Question 1

What do we mean by particle

Answer 1

An atom or molecule

Question 2

Describe the particle arrangement in a solid

Answer 2

Particles have a regular arrangement, have a fixed position, touch each other and small spaces

Question 3

Describe the particle arrangement in a liquid

Answer 3

Particles touch each other but have no fixed position and slide past each other. Some small spaces.

Question 4

Describe the particle arrangement in a gas

Answer 4

Particles are separated and move freely. Large spaces.

Question 5

What formula relates density, mass and volume?

Answer 5

Density = Mass / volume

Question 6

Define “physical change”

Answer 6

A change in which intermolecular forces are overcome or enabled but no chemical bonds are broken or made.

Question 7

Give a particle explanation for melting

Answer 7

Particles are given enough energy (through heating) to overcome the intermolecular forces that hold them in a fixed position.

Question 8

Give a particle explanation for freezing

Answer 8

Particles lose kinetic energy and move more slowly, reducing spaces between particles and allowing intermolecular forces to hold particles together

Question 9

What is condensing?

Answer 9

When a gas cools to form a liquid

Question 10

What is boiling?

Answer 10

When a liquid is heated to form a gas