Atomic structure

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Atomic structure
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Atomic Structure
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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
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The Atom
Electron
Nucleus
Shell or Orbit
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The Atom Hydrogen
Proton
Electron
Hydrogen has one proton, one electron and NO
neutrons
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The Atom Helium
Proton
Electron
Neutron
Helium has two electrons, two protons and two
neutrons
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Mass and atomic number
Particle Relative Mass Relative Charge
Proton 1 1
Neutron 1 0
Electron 0 -1
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The Atom Helium
Proton
Electron
Neutron
Helium has two electrons, two protons and two
neutrons
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The Atom Lithium
Electrons
Protons
Neutrons
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The Atom Beryllium
Electrons
Protons
Neutrons
Beryllium has four electrons, four protons and
five neutrons.
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The Atom Boron
Electrons
Protons
Neutrons
Boron has five electrons, five protons and six
neutrons.
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The Atom Carbon
Electrons
Protons
Neutrons
Carbon has six electrons, six protons and six
neutrons.
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The Atom Nitrogen
Electrons
Protons
Neutrons
Nitrogen has seven electrons, seven protons and
seven neutrons.
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The Atom Oxygen
Electrons
Protons
Neutrons
Oxygen has eight electrons, eight protons and
eight neutrons.
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The Atom Fluorine
Electrons
Protons
Neutrons
Fluorine has nine electrons, nine protons and ten
neutrons.
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The Atom Neon
Electrons
Protons
Neutrons
Neon has ten electrons, ten protons and ten
neutrons.
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The Atom Sodium
Electrons
Protons
Neutrons
Sodium has eleven electrons, eleven protons and
twelve neutrons.
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How many protons, neutrons and electrons?
1
11
16
H
B
O
1
5
8
23
35
238
Na
Cl
U
11
17
92
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Periodic table







Horizontal rows are called PERIODS
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The Periodic Table
Fact 1 Elements in the same group have the same
number of electrons in the outer shell (this
correspond to their group number)
H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
Ag I Xe
Pt Au Hg

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The Periodic Table
Fact 2 As you move down through the periods an
extra electron shell is added
H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
Ag I Xe
Pt Au Hg

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The Periodic Table
Fact 3 Most of the elements are metals
H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
Ag I Xe
Pt Au Hg

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The Periodic Table
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.
H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
Ag I Xe
Pt Au Hg

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Group 1 The alkali metals
Li
Na
K
Rb
Cs
Fr







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Group 1 The alkali metals
Some facts







1) These metals all have ___ electron in their
outer shell
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
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Group 0 The Noble gases
He
Ne
Ar
Kr
Xe
Rn







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Group 0 The Noble gases
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

1. Helium is lighter then air and is used in
   balloons and airships (as well as for talking in
   a silly voice)

1. Argon is used in light bulbs (because it is so
   unreactive) and argon , krypton and neon are used
   in fancy lights

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Group 7 The halogens
F
Cl
Br
I
At








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Group 7 The Halogens
Some facts







1) Reactivity DECREASES as you go down the group
(This is because the electrons are further away
from the nucleus and so any extra electrons
arent attracted as much).
2) They exist as diatomic molecules (so that
they both have a full outer shell)
3) Because of this fluorine and chlorine are
liquid at room temperature and bromine is a gas
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The halogens some reactions
1) Halogen metal

2) Halogen non-metal

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How shells fill

• 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.

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Electron structure
Consider an atom of Potassium
Potassium has 19 electrons. These are arranged
in shells
The inner shell has __ electrons The next shell
has __ electrons The next shell has __
electrons The next shell has the remaining __
electron
Electron structure 2,8,8,1
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Hydrogen H 1 electron 0 electron 0 electron 0 electron
Helium He 2 electron 0 electron 0 electron 0 electron
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Lithium Li 2 electron 1 electron 0 electron 0 electron
Beryllium Be 2 electron 2 electron 0 electron 0 electron
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Boron B 2 electron 3 electron 0 electron 0 electron
Carbon C 2 electron 4 electron 0 electron 0 electron
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Nitrogen N 2 electron 5 electron 0 electron 0 electron
Oxygen O 2 electron 6 electron 0 electron 0 electron
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Fluorine F 2 electron 7 electron 0 electron 0 electron
Neon Ne 2 electron 8 electron 0 electron 0 electron
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Sodium Na 2 electron 8 electron 1 electron 0 electron
Magnesium Mg 2 electron 8 electron 2 electron 0 electron
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Aluminium Al 2 electron 8 electron 3 electron 0 electron
Silicon Si 2 electron 8 electron 4 electron 0 electron
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Phosphorus P 2 electron 8 electron 5 electron 0 electron
Sulphur S 2 electron 8 electron 6 electron 0 electron
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Chlorine Cl 2 electron 8 electron 7 electron 0 electron
Argon Ar 2 electron 8 electron 8 electron 0 electron
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How the shells fill with electrons
Element Shell 1 Shell 2 Shell 3 Shell 4
Potassium 2 electron 8 electron 8 electron 1 electron
Calcium Ca 2 electron 8 electron 8 electron 2 electron
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The First Twenty Elements

• 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

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First 20 Elements continued

• 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

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First 20 Elements continued

• 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

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The Alkali metals

• 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.

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The Nobel gases

• 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.

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The Halogens

• 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.

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Displacement

• Fluorine can displace Chlorine, Bromine and
  Iodine.

F Cl
Br I
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Displacement

• Chlorine can displace Bromine and Iodine but it
  cannot displace Fluorine

Cl Br
I F

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Displacement

• Bromine can displace Iodine but it cannot
  displace Fluorine or Chlorine

Br I
F Cl

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Displacement

• Iodine cannot displace Iodine Fluorine, Chlorine
  or Bromine

I F
Cl Br
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Fluorine reacts with sodium chloride. Which
equation is correctly shows this reaction?

• F2 2Na ? 2NaF
• F Na ? NaF
• 2F 2Na ? 2NaF

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Which will displace?

• 2NaF Cl2 ? Yes or No
• 2NaBr Cl2 ? Yes or No
• 2KI I2 ? Yes or No
• 2LiCl I2 ? Yes or No
• 2NaBr I2 ? Yes or No
• 2NaBr F2? Yes or No
• Cl2 2NaBr ? Yes or No

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Four factors affecting Reaction Rate
Catalysts Temperature
Concentration Surface Area
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Catalyst

• A catalyst speeds up or slows down a reaction but
  does not get used up by the reaction.

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Temperature

• If we increase the temperature of a reaction by
  100C the rate will double this means the reaction
  will be complete in half the time.

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Concentration

• If we increase the concentration of a reactant
  the number of particles increase that in turn
  increases the chance of a collision and initiates
  a chemical reaction.

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Surface area

• The larger the particle size the smaller the
  relative area the slower the reaction.
• The smaller the particle size the greater the
  relative surface area and the faster the reaction.

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Group 1

• Lithium, sodium and potassium are all in group 1.
  
• They all have one electron in the outer shell.
• They are all metals.
• They react with group 7 to form metal halides.

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Group 7

• Fluorine ,Chlorine, Bromine and Iodine.
• They all have 7 electrons in their outer shell.
• They are all coloured.
• They form metal halides with group 1 metals.

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Group 0

• These are the noble gases.
• They have complete electron shells.
• The electron shells are full.
• They are unreactive.
• They are inert.
• They do not react.
• They include, Helium, Neon, Argon, Krypton, Xenon
  and Radon

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Halogens
Name Fluorine Colour Pale Yellow State Gas M.P. -220 B.P. -188
Chlorine Green Gas -101 -34
Bromine Brown Liquid -7 59
Iodine Slate grey Solid 114 184
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Reactions

• Sodium and Chlorine react to form ?
• Sodium Chloride.
• Iron and Chlorine react to form ?
• Iron Chloride.
• 2Na Cl2 ? 2NaCl.
• Fe Cl2 ? FeCl2.

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Uses of the Halogens

• Fluorine is put into water supplies to kill
  harmful bacteria and to help keep teeth healthy.
• Chlorine is used in swimming pools to bacteria in
  the water.
• Bromine is used in pesticides. Silver bromide is
  used in photography.
• Iodine is an antiseptic on cuts and grazes.