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Question 1

Describe particles in a solid [1]

Answer 1

Particles only vibrate about fixed positions, regular structure

Question 2

Describe particles in a liquid [1]

Answer 2

Particles can move around each other, collide often

Question 3

Describe particles in a gas [1]

Answer 3

Particles more freely and at random in all directions, collide less often than in a liquid

Question 4

Explain what happens to the temperature during melting [1]

Answer 4

The temperature stays constant as energy is used to weaken the intermolecular forces and change the substance from a solid to a liquid

Question 5

Explain what happens to the temperature during boiling [1]

Answer 5

The temperature stays constant as energy is used to break the intermolecular forces and change the substance from a liquid to a gas

Question 6

Describe an atom [1]

Answer 6

The smallest part of an element

Question 7

Describe a molecule [1]

Answer 7

A group of atoms covalently bonded together (e.g O₂ or H₂O)

Question 8

Describe an ion [1]

Answer 8

A charged particle (e.g Na+ or SO₄²-)

Question 9

Describe diffusion [1]

Answer 9

The process by which different substances mix as a result of the random motions of their particles

Question 10

Explain the factors that effect diffusion [2]

Answer 10

The higher the temperature the faster the rate of diffusion. The greater the molecular mass the slower the rate of diffusion.