1. Atomic Structure

2. The structure of the atom
The Ancient Greeks used to believe that everything was made up of very small particles. I did some experiments in 1808 that proved this and called these particles ATOMS:
Dalton
ELECTRON – negative, mass nearly nothing
PROTON – positive, same mass as neutron (“1”)
NEUTRON – neutral, same mass as proton (“1”)

3. Mass and atomic number 4 He 2 Particle Relative Mass Relative Charge
Proton 1
Neutron
Electron -1
MASS NUMBER = number of protons + number of neutrons He 2 4
SYMBOL
PROTON NUMBER = number of protons (obviously)

4. The Atom
Electron
Nucleus
Shell or Orbit

5. The Atom Hydrogen Proton Electron
Hydrogen has one proton, one electron and NO neutrons

6. The Atom Helium Proton Electron Neutron
Helium has two electrons, two protons and two neutrons

7. The Atom Helium Proton Electron Neutron
Helium has two electrons, two protons and two neutrons

8. The Atom Lithium
Electrons
Protons
Neutrons

9. The Atom Beryllium Electrons Protons Neutrons
Beryllium has four electrons, four protons and five neutrons.

10. The Atom Boron Electrons Protons Neutrons
Boron has five electrons, five protons and six neutrons.

11. The Atom Carbon Electrons Protons Neutrons
Carbon has six electrons, six protons and six neutrons.

12. The Atom Nitrogen Electrons Protons Neutrons
Nitrogen has seven electrons, seven protons and seven neutrons.

13. The Atom Oxygen Electrons Protons Neutrons
Oxygen has eight electrons, eight protons and eight neutrons.

14. The Atom Fluorine Electrons Protons Neutrons
Fluorine has nine electrons, nine protons and ten neutrons.

15. The Atom Neon Electrons Protons Neutrons
Neon has ten electrons, ten protons and ten neutrons.

16. The Atom Sodium Electrons Protons Neutrons
Sodium has eleven electrons, eleven protons and twelve neutrons.

17. HELIUM ATOM + - + - Shell proton neutron electron
What do these particles consist of?

18. How many protons, neutrons and electrons?1 11 16 H B O 1 5 8 23 35
238 Na Cl U 11 17 92

19. Ionic and Sub Atomic Particles
Ion = atom or group of atoms who gain or lose electron(s)
CATION +1 23
lose 1 electron in its outer shell Na
Number of proton = 11
Number of electron = 11 – 1 = 10 11
Number of neutron = 23 – 11 = 12 +2 24
lose 2 electrons in its outer shell Mg
Number of proton = 12 12
Number of electron = 12 – 2 = 10
Number of neutron = 24 – 12 = 12

20. Ionic and Sub Atomic Particles
ANION -2 16
gain 2 electron in its outer shell O
Number of proton = 8
Number of electron = = 10 8
Number of neutron = 16 – 8 = 8 -1 35
gain 1 electrons in its outer shell Cl
Number of proton = 17 17
Number of electron = = 18
Number of neutron = 35 – 17 = 18

21. ISOTOPES 1 2 3 H H H 1 1 1 Hydrogen Deuterium Tritium p = 1 n = 0
Isotopes = same number of protons different number of neutrons
= same AN; different MN

22. ISOBARS 3 3 H He 1 2 p = 1 n = 2 e = 1 p = 2 n = 1 e = 2
Isobars = same mass number (p + n)

23. ISOTONES 3 4 H He 1 2 p = 1 n = 2 e = 1 p = 2 n = 2 e = 2
Isotones = same number of neutrons

24. Determine these following pairs of atoms as isotope, isobar or isotone!39 39 1. 4. 19 20 K Cl F Ne
and
and 19 17 9 10
isobar
isotone 2. 30 31 5. 10 11 P S B B
and
and 15 16 5 5
isotone
isotope 3. 15 17 6.
105
106 N O Ag Cd
and
and 7 8 47 48
isotone
isotone

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