1. Mass to Energy Energy to Mass

2. Mass is usually conserved. Energy is usually conserved
Mass is usually conserved. Energy is usually conserved. Unless there is a nuclear reaction. In a nuclear reaction mass can change into energy and energy can change into mass.

3. To calculate the amount of energy each bit of mass is worth we use the equation E = m c 2 E stands for _______ measured in ______ m stands for _______ measured in ______ c stands for the _______ of _______ measured in ______

4. Sometimes a question might ask about amounts being changed into energy
Sometimes a question might ask about amounts being changed into energy. e.g. How much energy would you get if you converted g (5.586 x 10-4kg) into energy? (this is the mass of about 5 raindrops)

6. Sometimes the mass of atomic particles will be given
Sometimes the mass of atomic particles will be given. Work out the mass you start with and the mass you finish with. The difference is what is changed into energy.

7. The next slides are for year 13 only

8. Binding Energy
The binding energy of a nucleus is the energy required to disassemble the nucleus into the same number of free, unbound neutrons and protons. Essentially this is the amount of energy that holds the nucleus together.

9. Mass Deficit
Energy must come from somewhere. The binding energy of a nucleus is taken from the mass of the protons and neutrons that make up the nucleus. This means a nucleus has less mass than the same number of neutrons and protons. This loss of mass is called the mass deficit.

10. Binding Energy Per Nucleon
A nucleon is anything in the nucleus. This means _______ and _______ are nucleons. To find the binding energy per nucleon we divide the total binding energy by the number of nucleons (protons + neutrons).

11. The more binding energy per nucleon the more stable an atom is
The more binding energy per nucleon the more stable an atom is. Iron-56 is the most stable element because it has the most binding energy per nucleon.