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C4. Chemical Patterns. Card 1.
The Periodic Table.
G0/
G1 G2 G3 G4 G5 G6 G7
8
1 4
H He
P1
1 2
7 9 11 12 14 16 19 20
Li Be Copy in exam! B C N O F Ne
P2
3 4 5 6 7 8 9 10
23 24 27 28 31 32 35 40
Na Mg Al Si P S Cl Ar
P3
11 12 13 14 15 16 17 18
39 40 45 48 51 52 55 56 59 59 64 65 70 73 75 79 80 84
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
P4
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Top number is either Underlined Groups go down.
called the relative elements Group 1 is called The
atomic mass or mass are metals Alkali Metals.
number. – on the Group 7 is called The
left.. Halogens.
7 Elements in a group
Li have similar properties.
3
Bottom number is Read it like a book and
either called atomic proton numbers go up 1
number or proton with each element – 1,
number. 2, 3, 4 …
Periods go across the Periodic Table. Period 1 is H and He.
C4. Chemical Patterns. Card 2.
Group 1. The Alkali Metals.
Electron Melting Density
arrangement point
Lithium Li 2,1 181 0.5
Lower melting point
3
Sodium Na 2,8,1 98 0.97
Higher density
More reactive
11
Potassium K 2,8,8,1 63 0.86
19
Softer
Rubidium Rb 39 1.53
Caesium Cs 29 1.9
What do they have in common?
All metals
All soft
Silvery and shiny when freshly cut
Have one electron in outer shell
All react with water to make an alkaline solution (the
hydroxide) and hydrogen:
2Na + 2H2O 2NaOH + H2
Sodium + water sodium hydroxide + hydrogen
All react with chlorine to make salts:
2Na + Cl2 2NaCl
Sodium + chlorine sodium chloride
They react in a similar way because they all have one electron
in the outer shell. They each react slightly differently because
the atoms increase in size as you go down the group.
C4. Chemical Patterns. Card 3.
Flame tests and discovery of elements.
Each element has a unique
flame colour. It is different Lithium Red
to the flame colour of any
other element.
Sodium Yellow
Potassium Lilac
The line spectrum for an
element is unique. It is There are lines on the
different to the line spectrum spectrum of the sun
of any other element and is like which I haven’t seen
a fingerprint for the element. before. They don’t
match any elements that
have been discovered by
1868. I am going to call
the new element helium
after the Greek word
for sun (helios).
C4. Chemical Patterns. Card 4.
Group 7. The Halogens.
Molecules Appearance Boiling Electron
Not so good at bleaching
point arrangement
Fluorine F2 Yellow gas -188 2,7
Higher boiling point
Chlorine Cl2 Green gas -34 2,8,7
Less reactive
Bromine Br2 Deep red 58
liquid
Iodine I2 Grey solid 184
Cl Cl
What do they have in common?
All have two atoms in a molecule e.g.Cl2
All react with metals to make salts
2Na + Cl2 2NaCl
Sodium + chlorine sodium chloride
2Fe + 3Cl2 2FeCl3
Iron + chlorine iron chloride
All make toxic (poisonous) gases
All bleach dyes and indicators
All have seven electrons in the outer shell
Chlorine is used to kill
bacteria in water.
C4. Chemical Patterns. Card 5.
Hazard symbols.
Symbol Meaning Examples
Irritant – may irritate skin
and eyes
Harmful – limited health Iodine solid.
risks if eaten or touches
h
skin
Corrosive – can destroy living Sodium hydroxide
tissue if in contact (made when sodium
reacts with water).
Bromine liquid.
Highly flammable – can catch Lithium, sodium.
fire easily or makes a Hydrogen (made
flammable gas in water when sodium reacts
with water).
Toxic – causes serious health Chlorine gas and
risks if breathed in vapours from
bromine and iodine.
Oxidizing – reacts with
flammable chemicals and
gives off a lot of heat.
Group 1 and water – wear goggles, use a safety screen, wear
gloves, use tweezers to pick metal up.
Group 7 – always use these in a fume cupboard. Wear gloves
for bromine. Pick iodine up with tweezers. .
C4. Chemical Patterns. Card 6.
Equations.
You need to be able to write a word equation from a
sentence.
E.g. sodium reacts with water to make sodium hydroxide and
hydrogen.
Sodium + water sodium hydroxide + hydrogen
You need to know the state symbols:
Sodium(s) + water(l) sodium hydroxide(aq) + hydrogen(g)
(s) means the chemical is a solid
(l) means the chemical is a liquid
(g) means the chemical is a gas
(aq) means the chemical is dissolved in water to make a
solution (aq is short for aqueous)
When you balance equations, you are only
allowed to use big numbers in front of
formulae!
Na + Cl2 NaCl isn’t balanced
2Na + Cl2 2NaCl is correctly balanced
Na + Cl2 NaCl2 isn’t allowed because you
balanced using little numbers.
Try to remember these!
Water H2 O Sodium chloride NaCl
Hydrogen H2 Sodium bromide NaBr
Chlorine Cl2 Sodium hydroxide NaOH
Bromine Br2 Potassium chloride KCl
Iodine I2 Potassium hydroxide KOH
C4. Chemical Patterns. Card 7.
Structure of the atom.
All sodium atoms are exactly the same.
All sodium atoms have 12n, 11p and 11e.
Protons have a + charge and
neutrons have no charge so the
nucleus has a + charge overall.
Nucleus
12n
11p Protons have a + charge
and electrons have a –
charge. The atom has 11
11e around protons (11+) and 11
electrons (11-) so overall,
the nucleus the atom has no charge.
23
Protons = bottom number = 11
Na Electrons = bottom number = 11
Neutrons = top – bottom = 23 – 11 = 12
11
This is called the proton number or
the atomic number.
C4. Chemical Patterns. Card 8.
Electrons in atoms.
23
nucleus
Na
11 1st shell – holds 2
electrons
Nucleus
2nd shell – holds 8
electrons
3rd shell – holds 8
electrons
Electrons fill The electron arrangement
shells from the
1st shell
for sodium is 2.8.1
outwards.
G0/
G1 G2 G3 G4 G5 G6 G7
8
H He
P1
1 2
Groups go
Li Be down, periods B C N O F Ne
P2
2.1 2.2 go across. 2.3 2.4 2.5 2.6 2.7 2.8
Na Mg Al Si P S Cl Ar P3
2.8.1 2.8.2 2.8.3 2.8.4 2.8.5 2.8.6 2.8.7 2.8.8
It is in period 3 2.8.1 It is in group 1
because there because there is
are 3 shells of one electron in
electrons. the outer shell.
C4. Chemical Patterns. Card 9.
Salts.
Salts are made when
The ions are
metals react with non-
arranged regularly
metals.
so the crystals
Examples are sodium
also have a
chloride, potassium iodide,
regular shape.
lithium chloride …
Salts are Salts are made up
sometimes of ions. The ions
called ionic are held together
compounds. because + and –
Salts are attract each other
made up strongly. A lot of
from ions. energy is needed to
pull the ions apart
so the melting points
of salts are very
high.
Salts don’t conduct when
solid because the ions are fixed in
position and aren’t free to move
around.
Salts conduct if in
solution or molten because the ions
are charged and free to move
around.
C4. Chemical Patterns. Card 10.
Atoms, ions and molecules.
A molecule is a group of atoms
A particle can be an atom ...
joined together ...
O2
O H H
N O
He O
H2O
H O C O
CO2
An ion has a charge …...
A particle can be an ion.
•Na atom
Mg2+ Cl- •CuSO4 molecule
•Cl- ion
O2-
K+ •F- ion
•Na+ ion
A cation has a + charge … Anions are negative …
Purrrr Plus
Anne
C4. Chemical Patterns. Card 11.
Atoms into ions.
When elements react to make compounds, it is because the
atoms want to have a full outer shell of electrons.
Ions are made.
Chlorine gains an
-
electron to make a full
outer shell. Now it has
17 protons and 18
electrons so the overall
charge is -.
Cl- 2.8.8
Cl 2.8.7
Non-metals gain Metals lose
electrons to electrons to
make an ion make an ion
which is which is
negative. positive.
Na 2.8.1
Na+ 2.8
Sodium loses an
electron to make a full +
outer shell. Now it has
11 protons and 10
electrons so the overall
charge is +.
C4. Chemical Patterns. Card 12.
Formulae of ionic compounds.
Group
Group
Group
Group
Group
Group
Group
Group
1
2
3
4
5
6
7
0
H+
Group 0 don’t make ions
N3- O2- F-
Group 4 don’t make ions
Li+ Be2+ Learn these!
Na+ Mg2+ Al3+ S2- Cl-
K+ Ca2+ Br-
+ 2+ 3+ 3- 2- -
Bit below is Higher only!
Salt Positive ions Negative Formula
ions
Potassium chloride K+ Cl- KCl
Magnesium chloride Mg2+ Cl- MgCl2
Cl-
Aluminium chloride Al3+ Cl- AlCl3
Cl-
Cl-
Lithium oxide Li+ O2- Li2O
Li+
Lithium sulphide Li+ S2_ Li2S
Li+
Calcium oxide Ca2+ O2- CaO
