Atomic structure

1 × 10 to the power of -10 metres is the radius of what?

An atom

Which sub-atomic particle defines an element?

Protons

In a neutral atom, the number of electrons is _____ to the number of protons

Equal

What is the name for a form of an element that has the same number of protons but a different number of neutrons?

An isotope

In an element with fewer protons, it will be stable if it has ___ ___ number of protons and neutrons

The same

In an element with more protons, more ____ are needed to keep the nucleus stable

Neutrons

Nuclei with too many or too few neutrons are ____

Unstable

When a nucleus decays, what does it emit?

Radiation

What type of particle will be emitted if a nucleus has too few neutrons?

An alpha particle

A Helium -4 nucleus is known as an …

Alpha particle

Alpha decay causes the mass number of the nucleus to decrease by …

4

Alpha decay causes the atomic number of the nucleus to decrease by …

2

What is alpha radiation able to penetrate?

Skin/ paper

Alpha radiation has ____ ionising power

High

What is the range in the air of alpha radiation?

<5cm

A beta particle will be emitted if a nucleus has ___ ___ neutrons

Too many

What is the name given to the electron that is emitted when a neutron turns into a proton?

A beta particle

What is the relative mass of a beta particle?

0

Beta radiation causes the atomic number of the nucleus to _____ by one

Increase

True or false: the mass number of the nucleus stays the same after beta radiation

True

Which type of radiation is able to penetrate 3mm of aluminium foil?

Beta radiation

Beta radiation has ___ ionising power

Low

What is the approximate range in the air of a beta particle?

1m

Which type of radiation can penetrate lead/ concrete?

Gamma rays

Gamma rays have a very ____ ionising power

Low

What is the range in the air of a gamma ray?

>1km

Nuclear fission reactions are an example of ____ ____

Neutron emission

What is the full name for the machine that can detect all types of radioactive decay?

A Geiger - Muller tube

What is the term for when a neutron is emitted by radioactive decay?

Neutron emission

True or false: radioactive decay is a random process

True

One definition of a half life is ‘the time it takes for half of the _____ _____ to decay’

Unstable nuclei

One definition of a half life is ‘the time it takes for the ____ ____ to halve’

Count rate

What is the name for the number of decays recorded each second by a detector?

The count rate

If the half life of cobalt-60 is 5 years, and you have 100g of it, how much will be left after 15 years?

12.5

What process is defined as ‘exposing objects to beams of radiation’

Irradiation

What is the name of the process that occurs when an object has had a radioactive material introduced to it?

Contamination

True or false: irradiation does not cause the irradiated object to become radioactive

True

What type of radiation is used to kill cancerous tumours deep inside the body?

Gamma rays

What process is used to help preserve fruit by killing the bacteria, irradiation or contamination?

Irradiation

What process is used to sterilise surgical instruments, irradiation or contamination?

Irradiation

What process is used to make soft tissues show up in an x ray or gamma camera, irradiation or contamination?

Contamination

What process is used to check for leaks in pipes, irradiation or contamination?

Contamination