P4 GCSE Revision

P4 GCSE Revision

1. Atoms and Isotopes

   • When you nock of an electron, you are left with an ion.
   • If an atom becomes an ion it loses of gains 1 electron.
     • If it loses an electron it become 1+
     • If it gains an electron it becomes 1-

2. Half Life

   • Half life is the time taken for the radioactivity of an isotope to fall to half its value.
   • If you start with 400 atoms after 1 half life there would be 200 atoms, after two half lives there would be 100 atoms, after 3 half lifes there would be 50 atoms.

3. Alpha, Beta and Gamma Radiation.

   • Alpha Radiation
     • Least penetrating
     • Positively charged
     • Their path bends in a magnetic field
   • Beta Radiation
     • Leats ionising
     • Negatively charged.
     • Very small mass
     • Their path bends a lot in a magnetic field
   • Gamma Radiation
     • Most penetrating
     • No mass
     • No charge
     • Not affected by a magnetic field.

4. Electromagnetic Radiation