1. © Boardworks Ltd 2004 IGCSE Chemistry The Periodic Table

2. © Boardworks Ltd 2004 The Periodic Table Contents Elements and atomic number Arranging elements Electronic structure Patterns of behaviour Teacher resources

3. © Boardworks Ltd 2004 What are all substances made of? …to gold, an unreactive metal. From chlorine, a poisonous gas… From sodium, a reactive metal… There are millions of different substances in the world but what are they all made of? Elements the building blocks of all substances. There are about 100 different elements in a variety of forms. …to oxygen, a life-giving gas.

4. © Boardworks Ltd 2004 Properties of elements What is a property of an element? A property is any characteristic of an element. For example, here are some properties of sodium: It would be really useful to be able to predict properties of elements instead of having to remember them! metallic highly reactive solid but melts easily feels light (low density) Are there any patterns in the properties of elements?

5. © Boardworks Ltd 2004 Properties and atomic numberparticlecharge relative mass proton+11 neutron01 electron0.0005 Scientists discovered that the properties of elements seemed to depend on atomic number. What is the atomic number of an element? Atoms contain three types of particles: Where are these particles found in an atom?

6. © Boardworks Ltd 2004 What is atomic number? Atomic number = the number of protons in an atom proton electron neutron helium nucleus What are the particles in this helium atom? What is the atomic number of helium?

7. © Boardworks Ltd 2004 Atomic number and electrons Atoms of elements contain equal numbers of protons and electrons. Atoms of elements have no charge, they are neutral. What is the charge on a fluorine atom? 19F9 How are the number of electrons and atomic number related in a neutral atom? 9 protons 9 electrons 10 neutrons charge = +9 charge = - 9 charge = 0 total charge = 0 They are the same. How does this affect the charge of such atoms?

8. © Boardworks Ltd 2004 The Periodic Table Contents Elements and atomic number Arranging elements Electronic structure Patterns of behaviour Teacher resources

9. © Boardworks Ltd 2004 Atomic number and patterns K H LiNaBe MgAl PNOSClFNeArSiHeBC reactive metals unreactive gases reactive gases When scientists arranged elements in order of increasing atomic number they found patterns in their properties.

10. © Boardworks Ltd 2004 Positions of similar elements How many elements are there from one reactive metal to the next? How many elements are there from one reactive gas to the next? K H LiNaBe MgAl PNOSClFNeArSiHeBC 19 1 3114 1213 157816179101814256 8 8 Compare the positions of similar elements. reactive gasesreactive metals

11. © Boardworks Ltd 2004 Arranging elements Arranging these strips in rows… Divide the elements at set intervals, arrange them according to their properties and what patterns do you see? cut here K H LiNaBe MgAl PNOSClFNeArSiHeBC 19 1 3114 1213 157816179101814256 cut here NaMgAlPSClArSi H He LiBeNOFNeBC K

12. © Boardworks Ltd 2004 Arranging elements K He Al P S SiMg Na ArCl Be NOB CLi Ne F When elements are arranged according to their properties what patterns do you see and what element is missing? reactive metals unreactive gases reactive gases Similar elements go into the same columns. Hydrogen is an exception. This reactive gas is best positioned above the reactive metals. H hydrogen is a special case

13. © Boardworks Ltd 2004 The periodic table Arranging all the elements by atomic number and properties led to the creation of… the periodic table H He FrRa RfDbSgBhHsMt??Ac? KCa GaGeAsSeKrScTiVCrMnFeCoNiCuZnBr CsBa TlPbBiPoRnHfTaWReOsIrAuHgLaPtAt NaMg AlSiPSArCl LiBe BCNONeF RbSr InSnSbTeXeYZrNbMoTcRuPdAgCdRhI

14. © Boardworks Ltd 2004 Columns of elements H Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Ga In Tl Al B Ge Sn Pb Si C Sb Bi P N AsSe Te Po O S He Kr Ne Ar Rn Xe ScTiVCrMnFeCoNiCuZn YZrNbMoTcRuPdAgCdRh HfTaWReOsIrAuHgLaPt RfDbSgBhHsMt??Ac? Br At Cl F I What are columns of elements called? 765432 Groups 10 Group number transition elements

15. © Boardworks Ltd 2004 Rows of elements H He LiBeNOFNeBC NaMgAlPSClArSi KScTiVCrMnFeCoNiCuZnGaGeSeBrCaKrAs RbYZrNbMoTcRuPdAgCdInSnSbSrTeRhIXe CsBaHfTaWReOsIrAuHgTlPbBiPoLaAtPtRn FrRaRfDbSgBhHsMt??Ac? Periods What are rows of elements called? 1234567 Period number

16. © Boardworks Ltd 2004 H He Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeSeBrCaKr YZrNbMoTcRuPdAgCdInSnSbSrTeRh BaHfTaWReOsIrAuHgTlPbBiPoLaAtPt RaRfDbSgBhHsMt??Ac? AlP NO SCl FNe Ar Rn I Si Xe BC As What is the Group and Period of this element? Mg C Group 2 Group 4 Group 7 Cl K Group 1 MgCClK Name the position 765 4 3 21 0 2 3 4 5 6 7 Period 3 Period 2 Period 3 Period 4 1

17. © Boardworks Ltd 2004 H 1 He Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeSeBrCaKr YZrNbMoTcRuPdAgCdInSnSbSrTeRh BaHfTaWReOsIrAuHgTlPbBiPoLaAtPt RaRfDbSgBhHsMt??Ac? AlP NO SCl FNe Ar Rn I Si Xe BC As 3 11 19 37 55 87 4 2122 12 232425 26 27282930313234352036 394041424344464748495051385245 56727374757677798081828384578578 88 104105106107108109111112 89 110 1315 78 1617 910 18 86 53 14 54 2 56 33 Missing elements! In this periodic table the symbols are replaced by atomic numbers. Some of the numbers are missing – where? Two more periods of elements fit here but are only shown on some periodic tables. These are called the lanthanides and actinides.

18. © Boardworks Ltd 2004 The Periodic Table Contents Elements and atomic number Arranging elements Electronic structure Patterns of behaviour Teacher resources

19. © Boardworks Ltd 2004 Patterns 1: Metals and non-metals on the left and centre mostly on the right Where are different types of elements grouped together on the periodic table? metals non-metals in between metals and non-metals metalloids Metalloids aren’t type of rock music fan! Metalloids actually have some properties similar to metals and other properties similar to no-metals. Can you name a metalloid element?

20. © Boardworks Ltd 2004 Metals, non-metals and metalloids

21. © Boardworks Ltd 2004 H Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeSeBrCaKr YZrNbMoTcRuPdAgCdInSnSbSrTeRh BaHfTaWReOsIrAuHgTlPbBiPoLaAtPt RaRfDbSgBhHsMt??Ac? AlP NO SCl FNe Ar Rn I Si Xe He BC As silicon (Si) metalloid francium (Fr) metal scandium (Sc) metal krypton (Kr) non-metal cobalt (Co)metal Is this element a metal, non-metal or metalloid? Kr Sc Fr Si Co Metal, non-metal or metalloid?

22. © Boardworks Ltd 2004 Only two elements are liquids at room temperature. Where are elements of different states grouped together on the periodic table? on the left, in the centre and to the right only two elements are liquid solids liquids mostly on the far right gases mercurybromine Can you name these two elements? Patterns 2: Physical state

23. © Boardworks Ltd 2004 Physical state

24. © Boardworks Ltd 2004 H Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeSeBrCaKr YZrNbMoTcRuPdAgCdInSnSbSrTeRh BaHfTaWReOsIrAuHgTlPbBiPoLaAtPt RaRfDbSgBhHsMt??Ac? AlP NO SCl FNe Ar Rn I Si Xe He BC As krypton (Kr)gas Kr niobium (Nb)solid Nb barium (Ba) Ba solidnitrogen (N) N gasbromine (Br) Br liquid Is this element a solid, liquid or gas at room temperature? Solid, liquid or gas?

25. © Boardworks Ltd 2004 Patterns 3: Reactivity of metals more reactive What happens the reactivity of metals along a period? H Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeCa YZrNbMoTcRuPdAgCdInSnSbSrRh BaHfTaWReOsIrAuHgTlPbBiPoLaPt RaRfDbSgBhHsMt??Ac? Al What happens the reactivity of metals down a group? Which is the most reactive metal?

26. © Boardworks Ltd 2004 potassium (K) or lithium (Li) H Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeCa YZrNbMoTcRuPdAgCdInSnSbSrRh BaHfTaWReOsIrAuHgTlPbBiPoLaPt RaRfDbSgBhHsMt??Ac? Al calcium (Ca) or magnesium (Mg) calcium (Ca) or iron (Fe) copper (Cu) or barium (Ba) From the positions of these metals in the periodic table, which metal in each pair is the more reactive? Which metal is more reactive?

27. © Boardworks Ltd 2004 Patterns 4: Reactivity of non-metals more reactive What are the rules for the reactivity of the non-metals? 1. Group 0 is the most unreactive group of elements. 2. For the remaining non-metals, reactivity increases to the right of a period SeBrKr Te At P NO SCl F Ne Ar Rn I Si Xe He B C As more reactive Which is the most reactive non-metal? unreactiveunreactive and up a group.

28. © Boardworks Ltd 2004 neon (Ne) or iodine (I) Which non-metal is more reactive? SeBrKr Te At P NO SCl F Ne Ar Rn I Si Xe He B C As oxygen (O) or silicon (Si)fluorine (F) or chlorine (Cl) carbon (C) or oxygen (O) From the positions of these non-metals in the periodic table, which non-metal in the pair is the more reactive?

29. © Boardworks Ltd 2004 The Periodic Table Contents Elements and atomic number Arranging elements Electronic structure Patterns of behaviour Teacher resources

30. © Boardworks Ltd 2004 Patterns and atomic number What links atomic number and the properties of elements? The periodic table shows that patterns in the properties of elements are linked to atomic number. electrons H He FrRa RfDbSgBhHsMt??Ac? KCa GaGeAsSeKrScTiVCrMnFeCoNiCuZnBr CsBa TlPbBiPoRnHfTaWReOsIrAuHgLaPtAt NaMg AlSiPSArCl LiBe BCNONeF RbSr InSnSbTeXeYZrNbMoTcRuPdAgCdRhI

31. © Boardworks Ltd 2004 Patterns and electrons atomic number = number of protons atomic number = number of electrons in element’s atoms The properties of elements are hugely influenced by the number and arrangement of electrons in the atom. What links atomic number and the number of electrons? 1H14He27Li310B59Be4 As atomic number increases by one, the number of electrons also increases by one. So the elements in the periodic table are also arranged in order of the number of electrons.

32. © Boardworks Ltd 2004 Patterns and electrons How is layout of the periodic table related to the number and arrangement of electrons in these shells? Electrons are arranged in shells around an atom’s nucleus. cut here The point at which a new period starts is the point at which electrons begin to fill a new shell. How many electrons can the first three electron shells hold? K H LiNaBe MgAl PNOSClFNeArSiHeBC 19 1 3114 1213 157816179101814256

33. © Boardworks Ltd 2004 Rules for electron arrangements 2882,8,82882,8,8 The rules for the maximum number of electrons shells in the first three shells are: Electrons are arranged in shells around an atom’s nucleus. first shell maximum = 2 electrons second shell maximum = 8 electrons third shell maximum = 8 electrons This electron arrangement is written as:

34. © Boardworks Ltd 2004 Elements in Period 1 only have electrons in the first shell. 12 765 43 21 0 1 HHe The first shell can only hold a maximum of two electrons, so Period 1 only includes the elements hydrogen and helium. Why are there only two elements in Period 1? What is special about the outer shell of He? Electrons in Period 1

35. © Boardworks Ltd 2004 Elements in Period 2 all have a complete first shell. 2,12,22,3 2,4 2,5 2,6 2,7 2,8 765 43 21 0 2 LiBe BC NOFNe The second shell is completed one electron at a time going across Period 2 from left to right. What is special about the outer shell of Ne? What happens to electrons in the second shell in Period 2? Electrons in Period 2

36. © Boardworks Ltd 2004 2,8,12,8,22,8,3 2,8,4 2,8,5 2,8,6 2,8,7 2,8,8 Elements in Period 3 have complete first and second shells. 765 43 21 0 3 The third shell is completed one electron at a time going across Period 3 from left to right. What is special about the outer shell of Ar? NaMg AlSi PSClAr What happens to electrons in the third shell in Period 3? Electrons in Period 3

37. © Boardworks Ltd 2004 Patterns of electron arrangements 2,8,8,12,8,8,2 2,8,12,8,2 1 2,12,2 Consider the electron arrangements of the first 20 elements in the periodic table. 765 43 21 0 1 2,32,42,52,6 2,72,8 2,8,32,8,42,8,52,8,6 2,8,72,8,8 2 2 3 4 What is the pattern for the number of outer shell electrons in each group? Why do elements in the same group have similar chemical reactivity?

38. © Boardworks Ltd 2004 Why does reactivity increase going down the group? Going down Group 1 the outer electron becomes further from the nucleus and so is more easily lost in chemical reactions. The Group 1 metals are called the alkali metals. 1 2 3 2,1 Li 2,8,1 Na Group 1 elements have one electron in the outermost shell. Electrons in Group 1

39. © Boardworks Ltd 2004 Group 2 elements have two electrons in the outermost shell. 2,2 Be 2,8,2 Mg 2 2 3 In chemical reactions metals tend to lose their outer electrons to form positive ions. What is the charge on the ions of Group 2 elements? These elements lose the two outer electrons and form ions with a 2+ charge. Electrons in Group 2

40. © Boardworks Ltd 2004 Group 3 elements have three electrons in the outermost shell. 3 2 3 2,3 B 2,8,3 Al Metals lose their outer electrons to form positive ions. What is the charge on the ions of Group 3 elements? These elements lose the three outer electrons and form ions with a 3+ charge. Electrons in Group 3

41. © Boardworks Ltd 2004 Group 4 elements have four electrons in the outermost shell. 4 2 3 2,4 C 2,8,4 Si The elements at the top of Group 4 are non-metals. These elements don’t like to lose their electrons and prefer to share them with other atoms. What type of bonding is this? The elements at the top of Group 4 bond covalently. Electrons in Group 4

42. © Boardworks Ltd 2004 Group 5 elements have five electrons in the outermost shell. 5 2 3 2,5 N 2,8,5 P How many electrons do the elements shown need for a full outer shell? The Group 5 elements shown need three more electrons to achieve a full outer shell. Electrons in Group 5

43. © Boardworks Ltd 2004 Atoms form negative ions by gaining extra electrons. What type of ions will these Group 6 elements form? These Group 6 atoms can gain two extra electrons to complete their outer shell and form negative ions with a 2- charge. 6 2 3 2,6 O 2,8,6 S Group 6 elements have six electrons in the outermost shell. Electrons in Group 6

44. © Boardworks Ltd 2004 Group 7 elements have seven electrons in the outermost shell. 7 2 3 2,7 F 2,8,7 Cl These atoms need one extra electrons for a complete outer shell and form 1- ions. Why does reactivity increase going up Group 7? The incoming electrons are pulled more strongly into shells that are closer to the nucleus. Electrons in Group 7

45. © Boardworks Ltd 2004 Group 0 (or 8) elements all have a complete set of electrons in the outermost shell. 1 2 3 0 2 He 2,8 Ne 2,8,8 Ar Why are these elements so unreactive? The Group 0 atoms do not need to lose or gain any electrons to complete their outer shells which means they are unreactive. The Group 0 elements are called the noble (or inert) gases. Electrons in Group 0

46. © Boardworks Ltd 2004 H He Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeSeBrCaKr YZrNbMoTcRuPdAgCdInSnSbSrTeRh BaHfTaWReOsIrAuHgTlPbBiPoLaAtPt RaRfDbSgBhHsMt??Ac? AlP NO SCl FNe Ar Rn I Si Xe BC As Mg C 2, 8, 2 2, 42, 8, 7 Cl K 2, 8, 8, 1 MgCClK What is the electron arrangement? What is the electron arrangement in this element’s atoms? 765 4 3 21 0 2 3 4 5 6 7 1

47. © Boardworks Ltd 2004 Different types of elements

48. © Boardworks Ltd 2004 Periodic table quiz

49. © Boardworks Ltd 2004 The Periodic Table Contents Elements and atomic number Arranging elements Electronic structure Patterns of behaviour Teacher resources

50. © Boardworks Ltd 2004 H Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeSeBrCaKr YZrNbMoTcRuPdAgCdInSnSbSrTeRh BaHfTaWReOsIrAuHgTlPbBiPoLaAtPt RaRfDbSgBhHsMt??Ac? AlP NO SCl FNe Ar Rn I Si Xe He BC As Periodic table

51. © Boardworks Ltd 2004 H Li Na K Rb Cs Fr Be ScTi Mg VCrMnFeCoNiCuZnGaGeSeBrCaKr YZrNbMoTcRuPdAgCdInSnSbSrTeRh BaHfTaWReOsIrAuHgTlPbBiPoLaAtPt RaRfDbSgBhHsMt??Ac? AlP NO SCl FNe Ar Rn I Si Xe He BC As Periodic table