radioactivity

Question 1

What is an alpha particle?

Answer 1

Two protons and two neutrons (a helium nucleus)

Question 2

What is beta radiation?

Answer 2

Consists of fast moving electrons or positrons

Question 3

What is gamma radiation?

Answer 3

Consists of high energy photons with wavelengths less than 10^-13m. They travel at the speed of light and carry no charge

Question 4

Why is radioactive decay described as random?

Answer 4

We cannot predict when a particle nucleus in a sample will decay or which one will decay next
Each nucleus within a sample has the same chance of decaying per unit time

Question 5

Why is radioactive decay described as spontaneous?

Answer 5

Because the decay of nuclei is not affected by the presence of nuclei or other external factors such as pressure

Question 6

What is the half life of an isotope?

Answer 6

the average time it takes for half the number of active nuclei in the sample to decay

Question 7

When transferring radioactive sources how should you minimise danger?

Answer 7

Carry with a pair of tongs with long handles to keep the source as far from your body as possible
never handle a radioactive source with bare hands bitch

Question 8

What is activity? and what is its unit?

Answer 8

The rate at which nuclei decay in a radioactive source, measured in becquerels (Bq)

Question 9

define the decay constant

Answer 9

the probability of decay of an individual nucleus per unit time