beta decay

Question 1

how can an unstable nuclei undergo radioactive decay?

Answer 1

by beta decay.

Question 2

what are the two ways beta decay can take place?

Answer 2

• an electron is emitted.
• a positron is emitted.

Question 3

what happens in beta-minus decay?

Answer 3

a neutron in an unstable nuclei becomes a proton and an electron.

Question 4

what stays in the nucleus? (beta-minus)

Answer 4

proton stays within the nucleus.

Question 5

what is the beta-minus particle?

Answer 5

the electron

Question 6

what is emitted from the nucleus? (beta-minus)

Answer 6

the electron is emitted from the nucleus.

Question 7

what makes the electron a ‘fast-moving electron’?

Answer 7

it being emitted at high speeds.

Question 8

what does and doesn’t change in an element after beta-minus decay?

Answer 8

• the mass number does not change.
• the proton number increases.

Question 9

how much does the proton number increase by?

Answer 9

it increases by 1.

Question 10

what happens in beta-plus decay?

Answer 10

a proton in the nucleus becomes a positron and a neutron.

Question 11

what stays in the nucleus? (beta-plus)

Answer 11

the neutron stays within the nucleus.

Question 12

what is the beta-plus particle?

Answer 12

the positron.

Question 13

what is emitted from the nucleus? (beta-plus)

Answer 13

the positron is emitted.

Question 14

what does the positron take with is when it leaves the nucleus?

Answer 14

• a positive charge
• small amount of nuclear mass

Question 15

what does and doesn’t change in an element after beta-plus decay?

Answer 15

• the mass number does not change
• the proton number decreases

Question 16

how much does the proton number decrease by?

Answer 16

it decreases by 1.

Question 17

what are two uses of beta decay?

Answer 17

• radiocarbon dating (in unstable isotopes)
• PET scans