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© Boardworks Ltd 2004
KS4 Chemistry
The Periodic Table
© Boardworks Ltd 2004
The Periodic Table
Contents
Elements and atomic number
Arranging elements
Electronic structure
Patterns of behaviour
Teacher resources
© 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.
© 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!
metallichighly reactivesolid but melts easilyfeels light (low density)
Are there any patterns in the properties of elements?
© Boardworks Ltd 2004
Properties and atomic number
particleparticle chargecharge relative massrelative mass
proton +1 1
neutron 0 1
electron -1 0.0005
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?
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What is atomic number?
Atomic number = the number of protons in an atom
proton
electron neutron
heliumnucleus
What are the particles in this helium atom?
What is the atomic number of helium?
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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?
1919
FF99
How are the number of electrons and atomic number related in a neutral atom?
9 protons 9 electrons10 neutrons
charge = +9 charge = - 9 charge = 0
total charge = 0
They are the same.
How does this affect the charge of such atoms?
© Boardworks Ltd 2004
The Periodic Table
Contents
Elements and atomic number
Arranging elements
Electronic structure
Patterns of behaviour
Teacher resources
© Boardworks Ltd 2004
Atomic number and patterns
KH Li NaBe Mg Al PN O S ClF Ne ArSiHe B C
reactive metalsunreactive gases
reactive gases
When scientists arranged elements in order of increasing atomic number they found patterns in their properties.
© 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?
KH Li NaBe Mg Al PN O S ClF Ne ArSiHe B C
191 3 114 12 13 157 8 16 179 10 18142 5 6
8
8
Compare the positions of similar elements.
reactive gases reactive metals
© 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
KH Li NaBe Mg Al PN O S ClF Ne ArSiHe B C
191 3 114 12 13 157 8 16 179 10 18142 5 6
cut herecut here
NaMg Al P S Cl ArSi
H He
Li Be N O F NeB C
K
© Boardworks Ltd 2004
Arranging elements
K
He
Al P SSiMgNa ArCl
Be N OB CLi NeF
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.
Hhydrogen is a special case
© 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
Fr Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
K Ca Ga Ge As Se KrSc Ti V Cr Mn Fe Co Ni Cu Zn Br
Cs Ba Tl Pb Bi Po RnHf Ta W Re Os Ir Au HgLa Pt At
Na Mg Al Si P S ArCl
Li Be B C N O NeF
Rb Sr In Sn Sb Te XeY Zr Nb Mo Tc Ru Pd Ag CdRh I
© 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
As Se
Te
Po
O
S
He
Kr
Ne
Ar
Rn
Xe
Sc Ti V Cr Mn Fe Co Ni Cu Zn
Y Zr Nb Mo Tc Ru Pd Ag CdRh
Hf Ta W Re Os Ir Au HgLa Pt
Rf Db Sg Bh Hs Mt ? ?Ac ?
Br
At
Cl
F
I
What are columns of elements called?
765432
GroupsGroups
1 0Group number
transition elements
© Boardworks Ltd 2004
Rows of elements
H He
Li Be N O F NeB C
Na Mg Al P S Cl ArSi
K Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa KrAs
Rb Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh I Xe
Cs Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt Rn
Fr Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
PeriodsPeriodsWhat are rows of elements called?
1
2
3
4
5
6
7
Period number
© Boardworks Ltd 2004
H He
Li
Na
K
Rb
Cs
Fr
Be
Sc Ti
Mg
V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa Kr
Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh
Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt
Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
Al P
N O
S Cl
F Ne
Ar
Rn
I
Si
Xe
B C
As
What is the Group and Period of this element?
Mg
C
Group 2 Group 4Group 7
Cl
K
Group 1MgCClK
Name the position
7654321 0
2
3
4
5
6
7
Period 3Period 2Period 3Period 4
1
© Boardworks Ltd 2004
H1 He
Li
Na
K
Rb
Cs
Fr
Be
Sc Ti
Mg
V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa Kr
Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh
Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt
Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
Al P
N O
S Cl
F Ne
Ar
Rn
I
Si
Xe
B C
As
3
11
19
37
55
87
4
21 22
12
23 24 25 26 27 28 29 30 31 32 34 3520 36
39 40 41 42 43 44 46 47 48 49 50 5138 5245
56 72 73 74 75 76 77 79 80 81 82 83 8457 8578
88 104105106107108109 11111289 110
13 15
7 8
16 17
9 10
18
86
53
14
54
2
5 6
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.
© Boardworks Ltd 2004
The Periodic Table
Contents
Elements and atomic number
Arranging elements
Electronic structure
Patterns of behaviour
Teacher resources
© 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-metalsmetalloids
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?
© Boardworks Ltd 2004
Metals, non-metals and metalloids
© Boardworks Ltd 2004
H
Li
Na
K
Rb
Cs
Fr
Be
Sc Ti
Mg
V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa Kr
Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh
Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt
Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
Al P
N O
S Cl
F Ne
Ar
Rn
I
Si
Xe
He
B C
As
silicon (Si) metalloidfrancium (Fr) metalscandium (Sc) metalkrypton (Kr) non-metalcobalt (Co) metal
Is this element a metal, non-metal or metalloid?
KrSc
Fr
Si
Co
Metal, non-metal or metalloid?
© 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 rightgases
mercury bromine
Can you name these two elements?
Patterns 2: Physical state
© Boardworks Ltd 2004
Physical state
© Boardworks Ltd 2004
H
Li
Na
K
Rb
Cs
Fr
Be
Sc Ti
Mg
V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa Kr
Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh
Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt
Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
Al P
N O
S Cl
F Ne
Ar
Rn
I
Si
Xe
He
B C
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?
© Boardworks Ltd 2004
Patterns 3: Reactivity of metals
more reactive
mo
re reactive
What happens the reactivity of metals along a period?
H
Li
Na
KRbCs
Fr
Be
Sc Ti
Mg
V Cr MnFe Co Ni Cu ZnGaGeCaY Zr NbMoTc Ru Pd AgCd In Sn SbSr Rh
Ba Hf Ta W ReOs Ir AuHg Tl Pb Bi PoLa Pt
Ra Rf DbSg Bh Hs Mt ? ?Ac ?
Al
What happens the reactivity of metals down a group?
Which is the most reactive metal?
© Boardworks Ltd 2004
potassium (K) or lithium (Li)
H
Li
Na
KRbCs
Fr
Be
Sc Ti
Mg
V Cr MnFe Co Ni Cu ZnGaGeCaY Zr NbMoTc Ru Pd AgCd In Sn SbSr Rh
Ba Hf Ta W ReOs Ir AuHg Tl Pb Bi PoLa Pt
Ra Rf DbSg Bh Hs Mt ? ?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?
© 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
Se Br KrTe
At
PN O
S ClF Ne
Ar
Rn I
Si
Xe
HeB C
As
mo
re r
eact
ive
Which is the most reactive non-metal?
unreactive
and up a group.
© Boardworks Ltd 2004
neon (Ne) or iodine (I)
Which non-metal is more reactive?
Se Br KrTe
At
P
N O
S Cl
F Ne
Ar
Rn I
Si
Xe
HeB 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?
© Boardworks Ltd 2004
The Periodic Table
Contents
Elements and atomic number
Arranging elements
Electronic structure
Patterns of behaviour
Teacher resources
© 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
Fr Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
K Ca Ga Ge As Se KrSc Ti V Cr Mn Fe Co Ni Cu Zn Br
Cs Ba Tl Pb Bi Po RnHf Ta W Re Os Ir Au HgLa Pt At
Na Mg Al Si P S ArCl
Li Be B C N O NeF
Rb Sr In Sn Sb Te XeY Zr Nb Mo Tc Ru Pd Ag CdRh I
© 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?
11
HH11
44
HeHe22
77
LiLi33
1010
BB55
99
BeBe44
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.
© 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 herecut herecut 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?
KH Li NaBe Mg Al PN O S ClF Ne ArSiHe B C
191 3 114 12 13 157 8 16 179 10 18142 5 6
© Boardworks Ltd 2004
Rules for electron arrangements
22,88,88
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:
© Boardworks Ltd 2004
Elements in Period 1 only have electrons in the first shell.
1 2
7654321 0
1
H He
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
© Boardworks Ltd 2004
Elements in Period 2 all have a complete first shell.
2,1 2,2 2,3 2,4 2,5 2,6 2,7 2,8
7654321 0
2
Li Be B C N O F Ne
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
© Boardworks Ltd 2004
2,8,1 2,8,2 2,8,3 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.
7654321 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?
Na Mg Al Si P S Cl Ar
What happens to electrons in the third shell in Period 3?
Electrons in Period 3
© Boardworks Ltd 2004
Patterns of electron arrangements
2,8,8,1 2,8,8,2
2,8,1 2,8,2
1
2,1 2,2
Consider the electron arrangements of the first 20 elements in the periodic table.
7654321 0
1
2,3 2,4 2,5 2,6 2,7 2,8
2,8,3 2,8,4 2,8,5 2,8,6 2,8,7 2,8,8
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?
© 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
© 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
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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
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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
© 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
© 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
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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
© 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
© Boardworks Ltd 2004
H He
Li
Na
K
Rb
Cs
Fr
Be
Sc Ti
Mg
V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa Kr
Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh
Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt
Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
Al P
N O
S Cl
F Ne
Ar
Rn
I
Si
Xe
B C
As
Mg
C
2, 8, 22, 42, 8, 7
Cl
K
2, 8, 8, 1MgCClK
What is the electron arrangement?
What is the electron arrangement in this element’s atoms?
7654321 0
2
3
4
5
6
7
1
© Boardworks Ltd 2004
Different types of elements
© Boardworks Ltd 2004
Periodic table quiz
© Boardworks Ltd 2004
The Periodic Table
Contents
Elements and atomic number
Arranging elements
Electronic structure
Patterns of behaviour
Teacher resources
© Boardworks Ltd 2004
H
Li
Na
K
Rb
Cs
Fr
Be
Sc Ti
Mg
V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa Kr
Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh
Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt
Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
Al P
N O
S Cl
F Ne
Ar
Rn
I
Si
Xe
He
B C
As
Periodic table
© Boardworks Ltd 2004
H
Li
Na
K
Rb
Cs
Fr
Be
Sc Ti
Mg
V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa Kr
Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh
Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt
Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
Al P
N O
S Cl
F Ne
Ar
Rn
I
Si
Xe
He
B C
As
Periodic table