1. Atomic Structure Periodic Table Electron Configuration

4. ELECTRON – negative, mass nearly nothing PROTON – positive, same mass as neutron (“1”) NEUTRON – neutral, same mass as proton (“1”) 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

5. Nucleus Electron Shell or Orbit

6. Proton Electron Hydrogen has one proton, one electron and NO neutrons

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

8. ParticleRelative MassRelative Charge Proton11 Neutron10 Electron0 MASS NUMBER = number of protons + number of neutrons SYMBOL PROTON NUMBER = number of protons (obviously)

9. Electron Proton Neutron Helium has two electrons, two protons and two neutrons

10. Protons Neutrons Electrons

11. Protons Neutrons Electrons Beryllium has four electrons, four protons and five neutrons.

12. Protons Neutrons Electrons Boron has five electrons, five protons and six neutrons.

13. Protons Neutrons Electrons Carbon has six electrons, six protons and six neutrons.

14. Protons Neutrons Electrons Nitrogen has seven electrons, seven protons and seven neutrons.

15. Protons Neutrons Electrons Oxygen has eight electrons, eight protons and eight neutrons.

16. Protons Neutrons Electrons Fluorine has nine electrons, nine protons and ten neutrons.

17. Protons Neutrons Electrons Neon has ten electrons, ten protons and ten neutrons.

18. Protons Neutrons Electrons Sodium has eleven electrons, eleven protons and twelve neutrons.

19. How many protons, neutrons and electrons?

20. Mendeleev The periodic table arranges all the elements in groups according to their properties. Horizontal rows are called PERIODS Vertical columns are called GROUPS

21. HHe LiBeBCNOFNe Na MgMg AlSiPSClAr KCaFeNi CuCu ZnBrKr AgIXe Pt AuAu HgHg Fact 1: Elements in the same group have the same number of electrons in the outer shell (this correspond to their group number) E.g. all group 1 metals have __ electron in their outer shell These elements have __ electrons in their outer shell These elements have __ electrons in their outer shells

22. HHe LiBeBCNOFNe Na MgMg AlSiPSClAr KCaFeNi CuCu ZnBrKr AgIXe Pt AuAu HgHg Fact 2: As you move down through the periods an extra electron shell is added: E.g. Lithium has 3 electron in the configuration 2,1 Potassium has 19 electrons in the configuration __,__,__ Sodium has 11 electrons in the configuration 2,8,1

23. HHe LiBeBCNOFNe Na MgMg AlSiPSClAr KCaFeNi CuCu ZnBrKr AgIXe Pt AuAu HgHg Fact 3: Most of the elements are metals: These elements are metals This line divides metals from non-metals These elements are non- metals

24. HHe LiBeBCNOFNe Na MgMg AlSiPSClAr KCaFeNi CuCu ZnBrKr AgIXe Pt AuAu HgHg Fact 4: (Most important) All of the elements in the same group have similar PROPERTIES. This is how I thought of the periodic table in the first place. This is called PERIODICITY. E.g. consider the group 1 metals. They all: 1)Are soft 2)Can be easily cut with a knife 3)React with water

25. Li Na K Rb Cs Fr

26. 1) These metals all have ___ electron in their outer shell Some facts… 2) Reactivity increases as you go _______ the group. This is because the electrons are further away from the _______ every time a _____ is added, so they are given up more easily. 3) They all react with water to form an alkali (hence their name) and __________, e.g: Words – down, one, shell, hydrogen, nucleus Potassium + water potassium hydroxide + hydrogen 2K (s) + 2H 2 O (l) 2KOH (aq) + H 2(g)

27. He Ne Ar Kr Xe Rn

28. Some facts… 1) All of the noble gases have a full outer shell, so they are very _____________ 2) They all have low melting and boiling points 3) They exist as single atoms rather then diatomic molecules 4)Helium is lighter then air and is used in balloons and airships (as well as for talking in a silly voice) 5)Argon is used in light bulbs (because it is so unreactive) and argon, krypton and neon are used in fancy lights

29. F Cl Br I At

30. Some facts… 1) Reactivity DECREASES as you go down the group Decreasing reactivity (This is because the electrons are further away from the nucleus and so any extra electrons aren’t attracted as much). 2) They exist as diatomic molecules (so that they both have a full outer shell): Cl 3) Because of this fluorine and chlorine are liquid at room temperature and bromine is a gas

31. 1) Halogen + metal: Na + Cl - Na Cl + 2) Halogen + non-metal: H Cl + H Halogen + metal ionic salt Halogen + non-metal covalent molecule

32.  The first electron shell can only hold a maximum of two electrons.  The second electron shell can hold a maximum of eight electrons.  The third electron shell can also hold a maximum of eight electrons.  The fourth electron shell can also hold eight electrons.

33. Consider an atom of Potassium: Potassium has 19 electrons. These are arranged in shells… Nucleus The inner shell has __ electrons The next shell has __ electrons The next shell has the remaining __ electron Electron structure = 2,8,8,1

34. ElementShell 1Shell 2Shell 3Shell 4 Hydrogen H 1 electron0 electron Helium He 2 electron0 electron

35. ElementShell 1Shell 2Shell 3Shell 4 Lithium Li 2 electron1 electron0 electron Beryllium Be 2 electron 0 electron

36. ElementShell 1Shell 2Shell 3Shell 4 Boron B 2 electron3 electron0 electron Carbon C 2 electron4 electron0 electron

37. ElementShell 1Shell 2Shell 3Shell 4 Nitrogen N 2 electron5 electron0 electron Oxygen O 2 electron6 electron0 electron

38. ElementShell 1Shell 2Shell 3Shell 4 Fluorine F 2 electron7 electron0 electron Neon Ne 2 electron8 electron0 electron

39. ElementShell 1Shell 2Shell 3Shell 4 Sodium Na 2 electron8 electron1 electron0 electron Magnesium Mg 2 electron8 electron2 electron0 electron

40. ElementShell 1Shell 2Shell 3Shell 4 Aluminium Al 2 electron8 electron3 electron0 electron Silicon Si 2 electron8 electron4 electron0 electron

41. ElementShell 1Shell 2Shell 3Shell 4 Phosphorus P 2 electron8 electron5 electron0 electron Sulphur S 2 electron8 electron6 electron0 electron

42. ElementShell 1Shell 2Shell 3Shell 4 Chlorine Cl 2 electron8 electron7 electron0 electron Argon Ar 2 electron8 electron 0 electron

43. ElementShell 1Shell 2Shell 3Shell 4 Potassium2 electron8 electron 1 electron Calcium Ca 2 electron8 electron 2 electron

44.  Hydrogen 1,0,0,0  Helium 2,0,0,0  Lithium 2,1,0,0  Beryllium 2,2,0,0  Boron 2,3,0,0  Carbon 2,4,0,0  Nitrogen 2,5,0,0

45.  Oxygen 2,6,0,0  Fluorine 2,7,0,0  Neon 2,8,0,0  Sodium 2,8,1,0  Magnesium 2,8,2,0  Aluminium 2,8,3,0  Silicon 2,8,4,0

46.  Phosphorus 2,8,5,0  Sulphur 2,8,6,0  Chlorine 2,8,7,0  Argon 2,8,8,0  Potassium 2,8,8,1  Calcium 2,8,8,2

47.  Lithium, Sodium and Potassium have one electron in their outer shell and this is why they are found in group one of the periodic table.

48.  The Nobel gases have full outer shells and they are found in group 0 of the periodic table. Helium, Neon, Argon, Krypton, Xenon and Radon.

49.  Fluorine, Chlorine, Bromine and Iodine are the Halogens and they all have seven electrons in their outer shell. This is why they are found in group 7 of the periodic table.