Section pc 5

1
Section pc - 5

• Nuclear stuff

2
Some definitions

• Atomic number number of protons
• Can not change (and be the same element)
• Atomic mass number number of particles (can
  change and be the same element)

3
isotopes

• Atoms of an element with different numbers of
  neutrons
• C12 6 neutrons
• C14 8 neutrons
• HYDROGEN H1
• DEUTERIUM H2
• TRITIUM H3
• ISOTOPES ARE OFTEN UNSTABLE (RADIOACTIVE)

4
RADIATION TYPES

• ALPHA PARTICLE LARGE (2p 3n), NOT VERY
  PENETRATING
• BETA PARTICLE SMALLER (1 e), MORE PENETRATING
• GAMMA RAY SMALL (ENERGY) VERY PENETRATING

5
WOOD
PAPER
LEAD
ALPHA
BETA
GAMMA
6
DEFINITIONS

• RADIOACIVE DECAY
• GRADUAL BREAKDOWN OF NULCEI INTO SMALLER ATOMS
• RADIATION
• PARTICLES THAT ESCAPE WHEN AN ATOM DECAYS
• HALF LIFE
• HOW LONG IT TAKES FOR HALF OF A RADIOACTIVE
  SAMPLE TO DECAY

7
MORE

• NUCLEAR FISSION
• A HEAVY NUCLEUS ABSORBS NEUTRONS AND SPLITS
• TMI
• NUCLEAR FUSION
• 2 SMALL ATOMS COMBINE INTO A LARGER NUCLEUS
• FUTURE ENERGY SOURCE?