isotopes and nuclear radiation

Question 1

all atoms of same element

Answer 1

have same number of protons = AN
mn is protons + neutrons in nucleus

Question 2

What are isotopes

Answer 2

atoms which are diff form of same element with diff number of neutrons and same number of protons

All elements have diff isotopes, but there are usually one or two stable isotopes

Question 3

What do unstable isotopes do ?

Answer 3

decay into other elements + give out radiation to try to become more stable = this process is called radioactive decay

Question 4

radioactive substances..

Answer 4

split out one or more types of ionising radiation from their nucleus.

Alpha beta and gamma but also neutrons when they decay to rebalance the number of protons and neutrons.

Question 5

What is ionising radiation ?

Answer 5

knocks electrons off atoms creating + ions.
Ionising power of a radioactive source is how easily it can do this

Question 6

alpha particles - same as helium nucleus - emitted from nucleus

Answer 6

two protons and neutrons
don’t penetrate far into materials and stop quickly, few cm in air then absorbed by single sheet of paper
strongly ionising because they are large

Question 7

Beta

Answer 7

fast moving electron released by nucleus
Virtually no mass and charge of -1
moderately ionising, penetrate moderately far into materials before colliding and have a range in air of few metres

For every beta particle, a neutron in nucleus turned into proton

Question 8

Gamma

Answer 8

a type of EM radiation released by nucleus

Penetrate far into materials w/o being stopped and travel along distance through air.

weakly ionising = tend to pass through rather than collide with atoms but eventually hit smth and do damage.

absorbed by thick sheets of leads or metres of concrete