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Question 1

What is a particle?

Answer 1

A particle is a tiny bit of matter

Question 2

What are physical changes?

Answer 2

Physical changes are when a substance changes state or shape, or breaks into pieces. No new substances are made.

Question 3

What are chemical changes?

Answer 3

A chemical change is a change that produces one or more new substances. The properties of the new substances are often very different to the properties of the original substances.

Question 4

What’s the average size of an atom

Answer 4

1x10^-10

Question 5

What is a molecule?

Answer 5

A molecule is made from two or more atoms joined together. They are joined by attractive forces called chemical bonds.

Question 6

What is the particle model?

Answer 6

The particle model describes how particles are arranged and how they move in solids,liquids and gases.

Question 7

What is an atom?

Answer 7

The smallest particle of an element that still has its chemical properties

Question 8

What is a molecule?

Answer 8

A molecule is the smallest particle made from two or more atoms joined together. They are joined by attractive forces called chemical bonds.

Question 9

What is inside an atom?

Answer 9

It contains three subatomic particles
-protons
-neutrons
-electrons

Question 10

Protons

Answer 10

Relative mass: 1
Relative charge: +1

Question 11

Neutron

Answer 11

Relative mass: 1
Relative charge: 0

Question 12

Electron

Answer 12

Relative mass: 0.0005
Relative charge: -1

Question 13

What does the atomic number show?

Answer 13

How many protons are in an elements nucleus.

Question 14

What does the mass number show?

Answer 14

The total number of protons and neutrons

Question 15

What are isotopes?

Answer 15

Isotopes of an element are atoms with the same number of protons and electrons but a different number of neutrons.

Question 16

What are ions?

Answer 16

Ions are charged particles. They are formed when atoms, or groups of atoms, lose or gain electrons. This can happen during chemical reactions.

Question 17

How do you calculate the ratio of distance to diameter?

Answer 17

Ratio of distance to diameter =distance between atoms/diameter of atom

Question 18

What are the forces between particles?

Answer 18

Electrostatic forces of attraction between positive and negative charges.
(Strongest in solids, weakest in gases)

Question 19

What are limitations of the particle model?

Answer 19

Doesn’t take into account:
-The forces between particles
-The size of particles
-The space between particles

Question 20

What did dalton do?

Answer 20

Dalton suggested that atoms are smaller balls.
- all atoms of an element are identical
- different elements contain different types of atoms

Question 21

What did Thompson do?

Answer 21

Thompson discovered electrons.
-atoms are neutral overall
-atoms contain electrons
Plum pudding model

Question 22

What did Rutherford do?

Answer 22

Suggested that atoms have a positively charged nucleus containing most of its mass
-electrons orbit like planets in a solar system

Question 23

What did Bohr do?

Answer 23

Suggested that orbiting electrons are attracted to the oppositely charged nucleus and would rapidly spiral inwards.
-electrons occupy fixed energy levels, shells around the nucleus