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Starter Questions
Starter Questions
S4 Chemistry
Atomic Structure
NEW LEARNING
REVISION
Nuclide notations, isotopes and
relative abundance.
Atoms, electrons, shells,
nucleus and ions.
Average atomic mass.
Element symbols and types
Level 4
National 5
Starter Questions
1. How would you explain to an alien what
an element is?
The simplest substances all materials
can be broken down into.
2. Name 4 scientists who described what
atoms are like.
Dalton, Rutherford, Bohr, Thomson etc.
3. What differences are there between an
atom of hydrogen and an atom of
lithium?
Size, number of subatomic particles,
number of energy levels etc.
Lesson 1: Elements
Today we will learn to
Explain what an element is and why they
are grouped on a Periodic Table
We will do this by
Grouping elements cards and completing
quizzes to familiarise ourselves with
groups and periods
We will have succeeded if
We can identify at least 4 groups in the
periodic table.
Elements
The ancient Greeks were the first
to think about what things were
made of. They believed that
everything was made of various
combinations of just four elements
water, air, earth and fire.
Elements
John Dalton, in 1808, proposed that elements were the simplest substances
containing identical particles, called atoms, that couldn’t be broken down
any further.
The number of elements has gradually increased as our knowledge of
chemistry has improved. In 1600 there were only around a dozen known
substances that could be described as elements. By 1800 there were 31, by
1900 there were around 80 and in 2000 there were 113, though many of
these don’t occur naturally and are radioactive.
Grouping Elements
Group 1
Group 2
Group 3
Group 4
Reason
Reason
Reason
Reason
Grouping Elements
The Periodic Table consists of a series of columns, called groups, and also
rows, which are called periods. Some of the groups have names and the
elements making up the group have similar chemical properties.
ACTIVITY 2.2
Reactivity of Groups 1 & 7
Your teacher might demonstrate the reactivity of the alkali metals and/or
displacement reactions of the halogens.
Grouping Elements
Solid
Liquid
(only 2)
Metal
Gas
Non-metal
Grouping Elements
Naturally occurring
Made by scientists
Task
Complete Quick Test 1 in your booklet and
we will review as a class. You have 10
minutes! Circle the correct answers.
Quick Test 1 - Answers
Group
Metal or Non-Metal
Reactive or Non-Reactive
A
Alkali metals
metals / non-metals
reactive / non-reactive
B
Halogens
metals / non-metals
reactive / non-reactive
C
Noble gases
metals / non-metals
reactive / non-reactive
Quick Test 1 - Answers
NAME OF ELEMENT
a. Used in thermometers
Mercury
b. Used in weather balloons
Helium
c. Used in swimming pools
Chlorine
d. Makes up about 80% of the air
Nitrogen
e. Makes up about 20% of the air
Oxygen
f. Used to make jewellery
Silver, gold or platinum
g. Used as “lead” in pencils
Carbon (graphite)
h. Used to make computer chips
Silicon
i. Used in yellow street lamps
Sodium
j. Named after a planet
Plutonium, uranium or neptunium
k. Named after the scientist Albert Einstein
Einsteinium
l. Named after an American state
Californium
Exit Task
Mr Wrong
Explain why this student statement is
wrong…
“Elements are only grouped according to
their chemical properties.”
Starter Questions
Starter Questions
1. Give 3 different ways of grouping
elements.
2. Who is mainly responsible for the
modern Periodic Table?
3. What are the only two liquid elements?
Starter Questions
1. Give 3 different ways of grouping
elements.
Metal/non-metal; chemical properties;
man-made or not; atomic numbers, b.pt
etc
2. Who is mainly responsible for the modern
Periodic Table?
Dmitri Mendeleev
3. What are the only two liquid elements?
Mercury and bromine.
Lesson 2: Chemical Symbols
Today we will learn to
Correctly identify the elements from
their symbols and vice versa.
We will do this by
Reading about the history of the elements
and their names, and playing some
games!
We will have succeeded if
We can write the correct symbols for the
most common elements.
Chemical Symbols
To make it easier and quicker to write down the names of elements
scientists have developed unique symbols for each element. Letters from
the elements name are used to create a one or two letter symbol. As
many elements have the same starting letter some symbols use two
letters. Remember that the first letter is always a capital and the
second lowercase.
Element
Symbols with 1 letter
hydrogen
C
iodine
N
sulfur
V
Chemical Symbols
To make it easier and quicker to write down the names of elements
scientists have developed unique symbols for each element. Letters from
the elements name are used to create a one or two letter symbol. As
many elements have the same starting letter some symbols use two
letters. Remember that the first letter is always a capital and the
second lowercase.
Element
Symbols with 2 letters
chlorine
Mg
calcium
Sc
argon
Si
Chemical Symbols
Element
Antimony
Symbol
Sb
Latin Name
Stibium
Copper
Cuprum
Lead
Plumbum
Mercury
Hydragyrum
Gold
Aurum
Ag
Argentium
Fe
Ferrum
Na
Natrium
K
Kalium
Chemical Symbols
Many old elements are named after one of their properties or in
recognition of someone or somewhere e.g.
Bromine – Stench (Greek)
Cobalt – Underground goblin! (German)
Nobelium – After Alfred Nobel
Uranium – Planet Uranus
Strontium – Discovered in Strontian, Scotland
ACTIVITY 2.3
Naming New Elements, Symbol Bingo and
Words from Symbols Activities.
Objective Traffic Lights
How do you feel about the lesson objectives?
Red = don’t think I have grasped this
Amber = feeling OK about this, have just about got
there
Green = Confident I have achieved this
Starter Task
Complete Quick Test 2 in your booklet
and we will review as a class. You have 5
minutes! Circle the correct answers.
Answers
•
•
•
•
•
•
•
Quick Test 2
1. D,
2. A,
3. C,
4. B,
5. C,
6. A
Ask 3, Then Me!
Mark your answers and check with neighbours to see
why you got any wrong.
Lesson 3: The Idea of Atoms
Today we will learn to
Describe what an atom is and state the
properties of the sub-atomic particles.
We will do this by
Reviewing the structure of the atom from
S3 and working in pairs to describe it.
We will have succeeded if
We can describe in diagram, table AND
words what is inside an atom.
The Idea of Atoms
Activity 2.4
The Idea of Atoms
Take a sheet of paper and fold it carefully in half. Tear along the fold, take
one half and fold it in half, then tear along the fold again. Repeat this as
many times as you can. How small can you cut your piece of paper?
Thomson
Rutherford
Dalton
Bohr
The Idea of Atoms
Activity 2.5
History of the Atom Card Game
Your teacher may show you a video and then let you play this game. Use the
blank strips of paper to write out the correct descriptions.
The Idea of Atoms
The atom is believed to consist of three very small particles, the proton,
electron and neutron. The following diagram gives information about each
particle. The particles are so small we cannot weigh them in grams so we
use atomic mass units (a.m.u.).
Electrons
Mass = 0 a.m.u.
Charge = -1
Protons
Mass = 1 a.m.u.
Charge = +1
Neutrons
Mass = 1 a.m.u.
Charge = 0
DISCUSS
After discussion with your teacher and others, make sure you can name the
three sub-atomic particles, know where they are found in the atom and what
their mass and charge is.
The Idea of Atoms
Sub-atomic
particle
Position
Mass (a.m.u.)
Charge
Proton
Neutron
Electron
Build an Atom
http://phet.colorado.edu/en/simulation/build-an-atom
http://www.classzone.com/books/earth_science/terc/content/investigations/es0501/es0501page04.cfm
The Idea of Atoms
Exit Task
Question you have
about the lesson
Pyramid
Things you
have been
reminded of
today
Things you
have learned
today
Starter Questions
Starter Questions
. In an atom the
A. number of protons = the number of electrons
B.number of neutrons= the number of electrons
C. number of protons = the number of electrons +
neutrons
D. number of neutrons = the number of
electrons + protons
Starter Questions
The particles found in the nucleus are
A. protons and neutrons
B. protons and electrons
C. neutrons only
D. protons only
Starter Questions
Write the number of protons, electrons and
neutrons for each of the following:
a) 14
7
c) 31
15
N
b) 9
4
P
d) 45
21
Be
Sc
Lesson 4: Important Numbers
Today we will learn to
Identify the atomic number and mass
number of an element and explain what
they mean, and state that electrons are
found in shells.
We will do this by
Analysing nuclide notation and drawing
diagrams to show electron structure.
We will have succeeded if
We can draw a diagram and explain
important atom numbers to another pupil.
Important Numbers
Each element is fundamentally different
from any other, but importantly each
atom of one element must be identical in
some way. In 1913 Henry Moseley
discovered that the number of protons
in an element’s atom were always the
same and that the number of protons
for
each
element
was
unique.
Amazingly when he used this number
to order the elements in the Periodic
Table they matched the positions given
previously and that as you moved
across the table, going from one
element to the next, the number of
protons increased by just one.
The number of protons in an atom is now
called the ATOMIC NUMBER.
Important Numbers
The number of protons in an atom is now called the ATOMIC NUMBER.
Through experimentation it was found that atoms had no overall charge,
they were neutral. As each element has its own unique atomic number,
this means that the number of electrons will also be the same as the
atomic number.
So
Atomic number = number of protons = number of electrons in an
atom
Electrons are arranged around the nucleus in special layers called energy
levels or shells. The maximum number of electrons that can fit in a shell
depends on its position and shape.
The first shell closest to the nucleus is spherical and can hold a maximum of 2
electrons.
Important Numbers
The first shell closest to the nucleus is spherical and can hold a maximum of
2 electrons.
The second shell is larger and can contain a maximum of 8 electrons, with
electrons paired together if there are more than 4.
The third shell is larger again, it can also hold a maximum of 8 electrons, with
electrons paired together if there are more than 4.
Page 6 of your data booklet shows the electron arrangement of a number
of elements. After calcium, element 20, things get a bit more
complicated but you are not required to understand their arrangements
at this level.
Important Numbers
Element
Atomic
Number
Number of
Protons
Number of
electrons
carbon
hydrogen
magnesium
7
11
20
15
3
Electron
Arrangement
Important Numbers
In space below draw the electron arrangement of the following
elements, it doesn’t matter if you use dots or crosses to show the
electrons:
Helium
Chlorine
Calcium
Important Numbers
Most of the mass of an atom is found in the nucleus. As the nucleus
contains protons and neutrons the mass of different elements
tends to be different. As atoms are so small we say that the
number of protons and neutrons is the mass number. The atoms
are so small we cannot weigh them in grams so we use atomic
mass units (a.m.u.). If we know the atomic number and mass
number of an element then we can work out the number of
protons, electrons and neutrons.
So
mass number = number of protons + number of neutrons
number of neutrons = mass number — atomic number
Important Numbers
Element
Atomic
Number
lithium
Mass
Number
Number of
Protons
Number of
Electrons
7
17
uranium
Number of
neutrons
18
238
14
6
oxygen
10
22
11
82
126
Important Numbers
Nuclide Notation
Chemists can use nuclide notation to give lots of information about the
element:
a
b
X
a = mass number
X = symbol
b = atomic number
If we know the atomic number and mass number it is possible to work out the
number of protons, neutrons and electrons in the atom.
DISCUSS
After discussion with your teacher and others, make sure you can use nuclide
notation to work out the number of sub-atomic particles in an atom.
Important Numbers
Element
12
6
22
10
18
8
Atomic
Number
Mass
Number
20
40
Number of
Protons
Number of
neutrons
Number of
Electrons
C
Ne
O
9
4
11
5
Mind Map
Produce a mind map to summarise the lesson
today.
Starter Activity
ACTIVITY 2.8
Nuclide Notation Card Game
1 Groups of 3 or 4 pupils shuffle the cards and then deal out
3 cards.
2 The rest of the pack are placed face down and the first
card turned over.
3 The first player then chooses to take that card or the
next unseen card to help complete a set of three cards
describing a particular atom.
4 They then place down an unwanted card face up next to the
rest of the pack and the next player gets to go.
5 When a player has a set of the correct three cards they
are the winner.
Lesson 5: Isotopes
Today we will learn to
Explain that isotopes are atoms of the
same element with different masses.
We will do this by
Revising atomic structure and calculating
some relative atomic masses.
We will have succeeded if
We can draw a diagram and explain
important atom numbers to another
pupil.
Isotopes
Page 7 of your data booklet gives
relative atomic masses of selected
elements. You will notice that some
are not whole numbers, this is
because sometimes there are atoms
of the same element with different
masses. They are the same element
because they have the same atomic
number, but they have a different
mass because they have different
numbers of neutrons in their
nucleus.
Atoms of the same element but with
different
masses
are
called
ISOTOPES.
Isotopes
35
37
17
17
Cl
Symbol
Atomic Number
Number of Protons
Number of Electrons
Mass Number
Number of Neutrons
Cl
Isotopes
Chemically these atoms are exactly the same and exist naturally for
most elements. They can be identified using a machine called a
Mass Spectrometer which separates atoms according to their
mass. When a sample of an element is analysed the relative
proportion of each isotope is given as a percentage, called the %
abundance.
For example when chlorine gas is analysed it is found to have two
isotopes, one with a mass of 35 and one with a mass of 37. However
there is more of the chlorine 35 than the 37.
e.g. chlorine
35Cl
= 75% of all Cl atoms
37Cl = 25% of all Cl atoms
Isotopes
The RELATIVE ATOMIC MASS gives the average mass of all the isotopes
taking into account the relative proportions of each isotope.
RAM = (% abundance of isotope 1 x mass) + (% abundance of isotope 2 x mass)
100
RAM = (75 x 35) + (25 x 37)
100
RAM = 35.5 a.m.u.
Using the method shown above calculate the relative atomic masses of the
following elements:
1. Copper : 2 isotopes
= 75%
65 Cu = 25%
63 Cu
2. Silicon : 3 isotopes
28Si
= 93%
29Si
=
4%
30Si
=
3%
3.Boron : 2 isotopes
10B
=
20%
11B
=
80%
Tell me three things...
you have done well
you would like to find out more about
you know now that you didn’t know 50 minutes ago
Starter Task
Complete Quick Test 3 in your booklet
and we will review as a class. You have 5
minutes!
Answers
Quick Test 3
1. 18
2. D
3. 2, 8, 7
4.
5.
Atomic
Number
Symbol for
the element
Mass
number
Overall
charge of
the
particle
9
F
19
-1
Ask 3, Then Me!
Mark your answers and check with neighbours to see why you
got any wrong.
Lesson 6: Coloured Light
Today we will learn to
Use the structure of different atoms to
produce different coloured light.
We will do this by
Testing different metals in flame tests to
discover which colour they produce.
We will have succeeded if
We can work out which elements might be
best for our red distress flare.
Lesson 6: Coloured Light
When chemicals are heated up the electrons inside
the atoms get excited and move to energy levels
further away from the nucleus. The electrons then
move back to where they started but rather than
giving the energy back out as heat they give it out as
bands of light of a particular colour. As each element
has its own unique number of electrons,
each
element will often give out its own particular colour.
Normal light is made up of 7 colours, which you can
see in a rainbow or with a prism.
The diagram below shows the spectra of colour that
strontium gives out when it or its compounds are
heated. The predominance of the red bands causes
the flame colour to appear red.
Lesson 6: Coloured Light
ACTIVITY 2.9 Flame Colours
Heat a splint using a roaring blue Bunsen flame that has been soaked in a
solution containing the different metals to see what colour the flame is.
DISCUSS
After discussion with your teacher and others, make sure you can explain
how different metal compounds produce different coloured flames.
NOTES
Complete the table and compare your results with p6 of your data booklet:
Metal Compound Solution
Copper
Sodium
Strontium
Potassium
Flame Colour
Lesson 6: Coloured Light
ACTIVITY 2.10
Distress Flare
Your teacher may show you how to make a red distress flare in the
laboratory.
Distress flares are very similar to fireworks. They contain a fuel, an
oxidizing agent and chemicals that burn to produce colours and other
effects.
Exit Task
Shape and Colour
Use only shape and colour to create an
image of one thing you have learned today
Then, show it to a partner and see if they
can guess what the learning is.
Starter Task
Complete Quick Test 4 in your booklet
and we will review as a class. You have 10
minutes!
Starter Task - Answers
1a.
Type of particle
Number of particles
proton
19
neutron
20
electron
19
b. Different numbers of neutrons or different mass numbers
2ai.
81
Br
35
ii.
46
b.
They are the same or 50% each.
Lesson 7: Fireworks and flares
Research Task
After discussion with your teacher and
others, can you find out how a rocket
firework is made and produce a poster
explaining what the different parts of a
rocket are.
There are a number of good videos and
websites available that show how
fireworks are made, your teacher may
let you see these.
How fireworks work
Sparklers
Colours for fireworks
How it’s made - Rockets
Extension Task
Complete Quick Test 5 in your booklet
and we will review as a class. You have 5
minutes!
Definition
Choose three new words you have learnt in this topic and write
dictionary definitions.