Radioactivity Flashcards
(24 cards)
What did JJ Thompson discover?
Plum Pudding Model
Who did the gold foil experiment
Ernest Rutherford
What did James Chadwick discover
Neutrons are in the nucleus
What did Bohr theorise
Electrons or I tied the nucleus in shells
What stops alpha
Skin or paper e.t.c they are the least penetrating
Which is the biggest radioactive particle
Alpha
What is Beta?
A fast moving electron
What’s Gamma stopped by
Thick lead and thick concrete
What does Gamma move in?
Waves
What is half life
Time taken for the number of radioactive nuclei in an isotope to halve
What is an alpha particle made of
Two protons and two neutrons. Atomic number decreases by 2 and Mass number decreases by 4
What happens in Beta decay
The proton number increases by 1
Why don’t we put Alpha particles inside the body
It is highly ionising and able to cause a lot of damage it also finds it hard to penetrate the skin.
Why don’t we out beta particles inside the body?
Some of the radiation is able to escape
Why do we put Gamma into the body?
It’s the least ionising and the safest of the three to put in.
What is radioactive decay measured in?
Becquerels ( Bq )
Is radioactivity decay predictable?
No its a random process
Where does radioactive substances give their radiation out from?
The nucleus
When does irritation occur
When materials are near a radioactive source.
What’s the plum pudding model?
The atom is a ball of positive charge with electrons scattered within it
What’s an isotope
An element with the same number of protons but a different number of neutrons
What stops Beta?
Aluminium
Which is the most penetrating out of alpha beta and gamma?
Gamma
Why do some isotopes give out radiation
They are unstable and as a result decay
