Whole unit of radioactivity

Where is a proton located ?

in the nucleus

where are neutrons located?

in the nucleus

where are electrons located?

on the shells of the atom

What is the relative mass of a proton?

1

What is the relative charge of an electron?

-1

what is the relative charge of a neutron?

0

what is the relative mass of a neutron?

1

What is the relative mass of an electron?

0.0005 or 1/1840

what is the relative charge of a proton?

+1

What are isotopes?

atoms of the same elements that have same number of protons but different number of neutrons

What happens if an electrons falls to a lower orbit?

the atom emitted EM radiation

What happens if an electron moves to a higher orbit?

The atom has absorbed EM radiation

How does decay happen?

it is a random process

What element is Alpha radiation know as?

Helium

What are properties of alpha radiation?

• highly ionising

• weakly penetrative

Beta minus is often known as what?

electron

What are properties of beta minus?

• medium ionising

• medium penetration

What is beta plus commonly known as?

Positron

What are properties of beta plus?

• medium ionising

• medium penetration

What are characteristics of gamma radiation

• low ionising

• high penetration

What is background radiation?

weak radiation from underground rocks

What are some examples of background radiation?

• cosmic rays

• underground rocks

• medical rays

Name two objects that can detect radioactivity

photographic film and a Geiger-Muller Tube

How does photographic film detect radioactivity?

film goes darker when it absorbs radiation. It is worn as badges for people who work with radiation

How does a GM tube detect radiation?

each time it absorbs radiation, an electrical pulse is sent to the machine which produces a clicking sound. The greater amount of clicks the more radiation is present.

What experiment made people realize that the atom was mostly empty space?

The Rutherford experiment with gold foil

What can’t Alpha particles goo through?

paper

What can’t beta particles pass through

5mm of aluminum

what can’t gamma particle pass through?

thick sheet of lead or meters of concrete

What is activity?

number of decays per second

What is the units for activity?

Becquerel (bq)

What is the half life?

The time taken for a radioactive nuclei in a sample to decay

Can the half life be predicted?

no it is a random process

What safety measures must be taken when handling with something radioactive?

• glove

• correct PPE

• mask

• keep as much distance as possible

• use a utensil to touch it

What is contamination?

The source of radiation is transferred to an object

What is irradiation?

The source emits radiation which reaches the object