Particle model of matter

Question 1

Density

Answer 1

Density = mass / volume
Rho = m/V

Question 2

Solids

Answer 2

Strong forces of attraction hold the particles close together in a fixed, regular arrangement. The particles don’t have much energy so they vibrate about their fixed positions. The density is the generally highest in this state.

Question 3

Liquids

Answer 3

There are weaker forces of attraction between the particles. The particles are close together but are able to move past each other and form irregular arrangements. They have more energy than particles in a solid and move in random directions at low speeds. Liquids generally are less dense than solids.

Question 4

gases

Answer 4

There are almost o forces of attraction between the particles. The particles have more energy than liquids and solids so are free to move in random directions at high speeds. Gases generally have the lowest densities.

Question 5

Changes of state

Answer 5

When a substance changes state the number of molecules don’t increase so the mass does not change. They are physical changes and can be reversed.
Melting, Boiling, Condensing, Freezing and Sublimation