1. Nuclear notation and Binding energy
Contents:
Atomic notation
Isotopes
Whiteboard
Binding Energy
AMU
Making an atom
Calculating binding energy
Whiteboards
The curve of binding energy and the strong nuclear force (or why there is a limit to the periodic table)

2. X C Atomic notation A Z 12 6 X = Symbol (C, Au)
A = Atomic Mass Number = #nucleons
(Protons + Neutrons)
Z = Atomic Number = #protons C 12 6
Carbon A = 12, Z = 6. #neutrons?

3. C C Isotopes 12 6 14 6 Carbon 12 has 6 Neutrons
Carbon 14 is an isotope of Carbon
Chemically the same
Nuclear-lly different (it’s unstable)
C-14, C-12

4. Whiteboards:
Atomic Notation
1 | 2 | 3 | 4 | 5

5. What is the Atomic notation for tritium
What is the Atomic notation for tritium? (tritium is an isotope of Hydrogen with 2 neutrons)
Hydrogen has a Z = 1, A = 1 p + 2 n = 3
3/1 H

6. 10 protons, 12 neutrons. What is its atomic notation?
Z = 10, A = = 22, element 10 is Ne
22/10 Ne

7. How many neutrons in U 235? (235 = A) (1)
U is element 92
= 143 neutrons
143

8. How many neutrons in Pb 208? (208 = A) (1)
Pb is element 82
= 126 neutrons
126

9. How many neutrons in Kr 78? (1)
Kr is element 36
= 42 neutrons 42

10. Binding energy - the energy to take an atom apart
Unified Mass Units: (u)
C 12 (neutral atom) = u (defined)
(so 1 u is 1/12 of C12)
1 u = x kg = MeV
Electron = u (not useful)
Proton = u (not useful)
H (neutral atom) = u (very useful)
Neutron = u (very useful)

11. Put this on the back of your noteguide:
E = mc2
m = 1 u = x kg
c = 2.998x108 m/s
1 eV = 1.602x10-19 J
Let’s show that 1 u turned into pure energy is about MeV
(931.5x106 eV)

12. Binding energy - the energy to take an atom apart
H (neutral atom) = u (very useful)
Neutron = u (very useful)
1 u = MeV
To take an atom apart:
C 14 has a mass of u (p in text)
C 14 can be taken apart into:
6 H atoms: 6( u) (i.e. 6 p + 6 e)
8 Neutrons: 8( u)
Total “taken apart” mass = 6( u) + 8( u)
Total “taken apart” mass = u
Mass “defect” = u u = u
u - Represents energy needed to take atom apart
Binding energy = ( u)(931.5 MeV/u) = MeV

13. Binding energy - the energy to take an atom apart
H (neutral atom) = u
Neutron = u
1 u = MeV
Binding energy in general
Look up neutral atom mass
Break atom into H and n
Subtract neutral atom mass from taken apart mass
Multiply mass defect by Mev/u

14. Whiteboards:
Binding Energy
1 | 2 | 3

15. What is the binding energy for Nitrogen 13? (Z = 7)
N 13 mass = u
H = u
Neutron = u
1 u = MeV
Atom mass =
7H + 6n = 7( u) +6( u) = u
Binding energy = ( )931.5 MeV/u
= MeV
94.11 MeV

16. What is the binding energy for Carbon 12? (Z = 6)
C 12 mass = u (duh?)
H = u
Neutron = u
1 u = MeV
Atom mass =
6H + 6n = 6( u) +6( u) = u
Binding energy = ( – )931.5 MeV/u
= MeV
Binding energy per nucleon:
C 12: 92.16/12 = 7.68 MeV/nucleon
C 14: 105.3/14 = 7.52 MeV/nucleon (less)
92.16 MeV

17. What is the binding energy for Carbon 10? (Z = 6)
C 10 mass = u
H = u
Neutron = u
1 u = MeV
Atom mass =
6H + 4n = 6( u) +4( u) = u
Binding energy = ( )931.5 MeV/u
= MeV (Carbon 10 does not exist)
-139.7