P7 Radioactivity Flashcards
What did John Colton describe an atom as
Solid sphere
Who made the plum pudding model
JJ Thomson
Describe plum pudding model
Ball of charge with electrons and protons scattered within it
Which experiment did Ernest Rutherford create
Gold foil exsperiment
What did the gold foil exspose
Mass concentrated in centre most of mass is nucleus
Who thought of electrons being in shells
Niels Bohr
Who discovered neutrons
James Chadwick
What’s an isotope
Element with same protons but different neutrons
What happens when an isotope becomes unstable
They decay and give out radiation
What’s ionising radiation
When radiation that can knock electrons off atoms
What’s an alpha particle made out off
2 protons 2 neutrons emmited from nucleus
What are alpha particles stopped by
Thin objectes like skin and paper
What is beta radiation
Fast moving electrons
What can beta particles be stopped by
A piece of aluminium
When is radiation emmited
When an atoms neutron splits into a proton and electron
