Changes in the nucleus

Question 1

What did Rutherford’s scattering experiment prove?

Answer 1

Atoms are mostly empty space with a small concentrated positive nucleus in the centre

Question 2

What is an alpha particle made up of

Answer 2

2 protons and 2 neutrons

Question 3

What is an atomic number equal to

Answer 3

The number of protons in the atom

Question 4

What is the mass number of an atom

Answer 4

The number or protons+ the number of neutrons in an atom (Number of neutrons=Mass number-atomic number)

Question 5

Why do radioactive isotopes release energy

Answer 5

So they become more stable

Question 6

Alpha radiation

Answer 6

This occurs when an unstable atom releases an alpha particle

Question 7

Alpha decay

Answer 7

Mass number-Decreases by 4
Atomic number- Decreases by 2

Question 8

Beta particle/radiation

Answer 8

An electron created in and emitted from an unstable nucleus

Question 9

Beta decay

Answer 9

Atomic number-Increases by 1(so it changes to a different element because they are protons)
Atomic mass- Stays the same

Question 10

Gamma radiation

Answer 10

A type of electromagnetic wave that is uncharged with no mass. The atomic number and mass stay the same, so the element stays the same and there is no gamma decay

Question 11

Neutron emission

Answer 11

Neutrons are emitted by some radioactive substances when an alpha particle collides with them. The collision causes the nucleus to become more unstable and emit a neutron. Because the neutron emitted is uncharged, it can pass through substances easier than alpha and beta particles which are affected by the positively charged nucleus.