Foundation: P4 - Atoms & Radiation

Question 1

Define an atom

Answer 1

Atom: the smallest particle of an element

Question 2

Define atomic number

Answer 2

Atomic number: atomic number is the number of protons in an atom

Question 3

Define mass number

Answer 3

Mass number: mass number is the total number of protons and neutrons in an atom

Question 4

Define an isotope

Answer 4

Isotope: isotopes are atoms which have the same number of protons but a different number of neutrons

Question 5

Define radioactive decay

Answer 5

Radioactive decay: when unstable atoms release radiation

Question 6

Define half-life

Answer 6

Half-life: the time taken for the number of radioactive nuclei in a sample to halve OR the time taken for the activity of a radioactive sample to halve

Question 7

Define ionising radiation

Answer 7

Ionising radiation: radiation that can cause changes in the atoms it passes through

Question 8

Define contamination

Answer 8

Contamination: when a radioactive source is on or in something

Question 9

Define irradiation

Answer 9

Irradiation: exposure to ionising radiation

Question 10

Describe the structure of an atom

Answer 10

Protons and neutrons in the nucleus, electrons on electron shells

Question 11

Name four types of ionising radiation

Answer 11

Alpha, beta, gamma, neutrons

Question 12

State what type of material can block alpha radiation.

Answer 12

Paper can block alpha radiation.

Question 13

State what type of material can block beta radiation.

Answer 13

Aluminium can block beta radiation.

Question 14

State what type of material can block gamma radiation.

Answer 14

Lead can partially block gamma radiation.

Question 15

Rank the radiations from most to least ionising.

Answer 15

(most ionising) alpha, beta, gamma (least ionising)

Question 16

Rank the radiations from greatest to shortest penetration depth.

Answer 16

(greatest penetration depth) gamma, beta, alpa (shortest penetration depth)