Exam Revision - Definitions

Question 1

The helium nucleus emitted when an unstable larger nucleus decays

Answer 1

Alpha particle

Question 2

Equal to the number of protons in the nucleus (and is the same for every atom of the same element).

Answer 2

Atomic Number

Question 3

A stream of particles and/or energy from a radioactive source.

Answer 3

Radiation

Question 4

A particle found in the nucleus of an atom that does not have an electrical charge.

Answer 4

Neutron

Question 5

A particle found inside an atom, such as a proton, neutron or an electron.

Answer 5

Subatomic Particles

Question 6

A reaction that is self-sustaining as a result of the one step starting another.

Answer 6

Chain reaction

Question 7

The time it takes for half of an isotope to decay.

Answer 7

Half-life

Question 8

The splitting of a nucleus into two smaller pieces.

Answer 8

Nuclear fission

Question 9

A process where atoms rearrange to form a new substance.

Answer 9

Chemical reaction

Question 10

A written representation of a chemical reaction.

Answer 10

Chemical equation

Question 11

A substance that comes out of (is made from) a chemical reaction.

Answer 11

Product

Question 12

A substance that is put into a chemical reaction.

Answer 12

Reactant

Question 13

A chemical equation that uses the chemical symbols to represent the chemical reaction.

Answer 13

Formula Equation

Question 14

A universal law that states that mass cannot be created or destroyed.

Answer 14

Conservation of mass

Question 15

A chemical reaction that happens without the input of energy.

Answer 15

Spontaneous

Question 16

A chemical equation that does not have the same amount and type of atoms in the reactants and the products.

Answer 16

Unbalanced

Question 17

A substance that changes colour under different acidic/basic conditions.

Answer 17

Indicator

Question 18

A chemical reaction in which a fuel reacts with oxygen and produces heat as one of the products.

Answer 18

Combustion

Question 19

A chemical compound that contains only carbon and hydrogen.

Answer 19

Hydrocarbon

Question 20

A chemical reaction that takes in heat energy.

Answer 20

Endothermic

Question 21

Reaction of a substance with oxygen.

Answer 21

Oxidation

Question 22

The phenomenon whereby gases in the Earth’s atmosphere trap heat energy.

Answer 22

Greenhouse effect.

Question 23

Storing carbon dioxide in geological formations.

Answer 23

Geosequestration

Question 24

A circuit which has multiple loops.

Answer 24

Parallel circuit

Question 25

The device used to measure the difference in potential energy between two points in a circuit.

Answer 25

Voltmeter

Question 26

The unit of resistance.

Answer 26

Ohm

Question 27

An energy source which converts stored chemical potential energy to electrical energy.

Answer 27

Battery

Question 28

The point where the battery connects to the circuit.

Answer 28

Electrode

Question 29

A battery which contains a liquid electrolyte.

Answer 29

Wet cell battery

Question 30

A material which does not allow an electric current s through it.

Answer 30

Insulator

Question 31

A wave where the particles in the medium vibrate at right angles to, the direction the wave is travelling in.

Answer 31

Transverse wave

Question 32

A region which contains no particles.

Answer 32

Vacuum

Question 33

The angle between the reflected ray and the normal.

Answer 33

Angle of reflection

Question 34

An image which is larger than the object.

Answer 34

Enlarged image

Question 35

A curved piece of transparent material which focuses light to produce an image.

Answer 35

Lens

Question 36

Material which light can be transmitted through.

Answer 36

Transparent material.

Question 37

Material in which some light is reflected and some passes through.

Answer 37

Translucent material

Question 38

Material in which no light passes through as it is either absorbed or reflected.

Answer 38

Opaque material.

Question 39

An image which forms when light rays actually cross.

Answer 39

Real image

Question 40

The measure of how easily light travels through different media.

Answer 40

Refractive index

Question 41

A flat mirror.

Answer 41

Plane mirror

Question 42

The number of crests which pass a certain point in one second.

Answer 42

Frequency

Question 43

An image which is smaller than the object.

Answer 43

Diminished image.

Question 44

A lens which curves inwards.

Answer 44

Concave lens

Question 45

A lens which curves outwards.

Answer 45

Convex mirror

Question 46

The angle between the refracted ray and the normal.

Answer 46

Angle of refraction.

Question 47

The angle between the incoming light ray and the normal.

Answer 47

The angle of incidence.

Question 48

The point where parallel light rays converge after going throughout lens.

Answer 48

Focus

Question 49

An image which is right-side up.

Answer 49

Upright image.

Question 50

An image which is upside down.

Answer 50

Inverted image

Question 51

An image which is mirrored.

Answer 51

Laterally inverted image

Question 52

Light which contains all other colours of light.

Answer 52

White light

Question 53

An imaginary line which stands at right angles to the surface of a lens or mirror.

Answer 53

Normal

Question 54

An image which forms when light rays appear to cross but do not actually cross.

Answer 54

Virtual image

Question 55

The distance from one crest to the next.

Answer 55

Wavelength

Question 56

The top of a wave.

Answer 56

Crest

Question 57

The bottom of the wave.

Answer 57

Trough

Question 58

The middle part of a wave.

Answer 58

Equilibrium

Question 59

The distance between the middle of a wave and the top or bottom of the wave.

Answer 59

Amplitude

Question 60

The fundamental particles of matter, made up of protons, neutrons and electrons.

Answer 60

Atom

Question 61

Atoms with the same number of protons but a different number of neutrons.

Answer 61

Isotopes

Question 62

The mass of protons, neutrons and electrons that make up an atom.

Answer 62

Atomic weight.

Question 63

A negatively charged particle in the atom, which moves in space around the nucleus.

Answer 63

Electron

Question 64

A positively charged particle in the nucleus of an atom.

Answer 64

Proton

Question 65

The spontaneous disintegration of certain atomic nuclei accompanied by the emission of alpha particles, beta particles or gamma radiation.

Answer 65

Radioactivity

Question 66

An electron or positron (which has the same mass as an electron but the opposite charge) emitted when an unstable nucleus decays.

Answer 66

Beta particle

Question 67

Why do atoms form ions?

Answer 67

To get full valence shells, which are more stable

Question 68

What is an ion?

Answer 68

An atom with an electrical charge.

Question 69

If there is two electron shells, which of these has the lowest energy.

Answer 69

The shell closest to the nucleus.

Question 70

How do ionic bonds form?

Answer 70

By the transfer of electrons from one atom to another.

Question 71

What is electrostatic attraction?

Answer 71

When opposite electrical charges are attracted to each other.

Question 72

Positively charged ion.

Answer 72

Cation

Question 73

Negatively charged ion.

Answer 73

Anion

Question 74

The unit for voltage.

Answer 74

Volt

Question 75

Opposition to the flow of the current.

Answer 75

Resistance

Question 76

The difference in potential energy between two points in a circuit.

Answer 76

Voltage

Question 77

The unit for current.

Answer 77

Ampere

Question 78

A circuit where all components are on a single loop.

Answer 78

Series circuit

Question 79

The positive electrode.

Answer 79

Cathode

Question 80

The negative electrode.

Answer 80

Anode

Question 81

The device used to measure the strength of a current.

Answer 81

Ammeter

Question 82

A material which allows an electric current to pass through it.

Answer 82

Conductor

Question 83

The flow of charge around a circuit.

Answer 83

Current

Question 84

A solution which conducts electricity.

Answer 84

Electrolyte

Question 85

A loop of wire which connects an energy source to an energy user.

Answer 85

Circuit