Chapter 8: Radioactivity (Key Definitions)

Question 1

What is radioactivity?

Answer 1

Radioactivity is the spontaneous breaking up of unstable nuclei with the emission of one or more types of radiation

Question 2

(____) is the spontaneous breaking up of unstable nuclei with the emission of one or more types of radiation

Answer 2

Radioactivity

Question 3

What is a nuclear reaction?

Answer 3

A nuclear reaction is a process that alters the composition, structure or energy of an atomic nucleus

Question 4

A (___) is a process that alters the composition, structure or energy of an atomic nucleus.

Answer 4

Nuclear reaction

Question 5

What happens when an atom loses an alpha particle?

2

Answer 5

• It changes into an atom of the element two places before it in the Periodic Table
• The mass number of the parent atom decreases by four

Question 6

What has to be lost for an atom to be changed into an atom of the element two places before it in the Periodic Table and for the mass number of the parent atom to decrease by four?

Answer 6

An atom has to lose an alpha particle

Question 7

What happens when an atom loses a beta particle?

2

Answer 7

• the atom changes into an atom of the element one place after it in the Periodic Table
• the mass number of the parent atom stays the same

Question 8

What does an atom have to lose for it to change into an atom of the element one place after it in the Periodic Table and for the mass number of the parent atom to stay the same?

Answer 8

An atom has to lose a beta particle

Question 9

What is a half-life of an element?

Answer 9

The half-life of an element is the time taken for half of the nuclei in any given sample to decay

Question 10

The (___) of an element is the time taken for half of the nuclei in any given sample to decay

Answer 10

Half-life

Question 11

What is a radioisotope?

Answer 11

A radioisotope is a radioactive isotope

Question 12

What is a radioactive isotope called?

Answer 12

A radioisotope

Question 13

What is radiocarbon dating (carbon dating)

2

Answer 13

• radiocarbon dating (carbon dating) is a technique used to determine the age of an object containing carbon
• it is based on the ratio of carbon-14 to carbon-12 in the object

Question 14

(__) is a technique used to determine the age of an object containing carbon and is based on the ratio of carbon-14 to carbon-12 in the object

Answer 14

radiocarbon dating (carbon dating)