Stable And Unstable Nuclei Flashcards
There are several different forces acting on the nucleons in a nucleus. What does the electrostatic forces come from
The protons’ electric charges
What does the strong nuclear force do
Binds nucleons together
There are several different forces acting on the nucleons in a nucleons. What is the gravitational forces due to
The masses of the particles
The repulsion from the electrostatic force is much, much …… Than the gravitational attraction
Bigger
If the only forces acting in the nucleus where electrostatic and gravitational, what would happen to the nucleons
They would fly apart
So there must be another attractive force that holds the nucleons together. What is it
The STRONG NUCLEAR FORCE
The strong nuclear force has a very …… Range
Short
Only hold nucleons together when they’re separated by up to a few femtometres
After a few femtometres what happens to the strength of the STRONG NUCLEAR FORCE
Quickly falls
The strong nuclear force works ….. Between all nucleons
Equally
Same size whether it’s proton-proton, neutron-neutron, proton-neutron
At very small separations the strong nuclear force is what
Repulsive
Otherwise nothing stopping it from crushing nucleons to a point
The size of the strong nuclear force varies with nucleon ……
Separation
After what distance does the strong nuclear force become attractive
0.5 fm
After what distance does the attractiveness of the strong nuclear force fall rapidly towards zero
3 fm
The electrostatic repulsion force extends over a much …. Range
Larger
Why does alpha emission only happen in VERY big atoms
The nuclei are TOO BIG for the strong nuclear force to keep them STABLE
What happens to the PROTON and NUCLEON number when an ALPHA particle is emitted
The proton number decreases by 2
The nucleon number decreases by 4
Where does beta-minus emission happen
Neutron-rich nuclei
I.e. Have too many more neutrons than protons in their nucleus
What is emitted in a beta-minus decay
ELECTRON from the nucleus along with an ANTINEUTRINO
What happens to one of the neutrons when a nucleus ejects a beta particle
Changes into a proton
What happens to the PROTON and NUCLEON number when a beta particle is emitted
The proton number increases by 1
The nucleon number stays the same
What does the tiny neutral particle called an ANTINEUTRINO carry away
Some energy and momentum
