Unit 2 Flashcards
Radiation (17 cards)
What is radiation?
Ionise which can ionise molecules in the air
Where does radiation come from?
The nucleus. If there is an excess of either protons or neutrons the atom will try to get rid of them
What makes a nucleus unstable?
If the forces among the particles that make up the nucleus aren’t balanced it can result in excess protons or neutrons it will try to get rid of them
What is an alpha particle?
A helium nucleus. Two protons two neutrons
What bends an alpha particle?
Electric and magnetic fields but not as much as the beta particle as alpha is heavier
Properties of alpha particle?
highly ionizing (attracts electrons)
Stopped by paper (low penetrating power)
heavy and slow
What is a beta particle?
A fast moving electron
Properties of beta particle?
Can be bent by magnetic or electric field, more so than alpha as its lighter
Not as ionising as alpha but more ionising than gamma
What is gamma radiation?
High energy Electromagnetic waves
Properties of gamma rays?
High penetrating power
Weak ionising power (no charge)
not affected by electric/magnetic fields
kills cells
How do electric/magnetic fields affect all types of radiation?
Alpha- Bends
Beta - Bends more than alpha
Gamma- Isn’t affected (no charge)
Half life equation for decay constant?
0.693/decay C
What is half life?
The time it take for half the sample to decay
Describe the process of alpha decay
occurs most often in big nuclei that have too large proton to neutron ratio, it will emit a particle with two neutrons two protons
What happens when a positron collides with an electron?
They form gamma rays
When does electron capture occur?
when a nucleus has too many protons to neutrons
What is electron capture?
when a proton captures an electron and changes it to a neutron
