National 4
Unit 1
Atoms, Elements
and Periodic Table
1
The periodic table
Learning Intentions:
 The periodic table contains all the known elements in the world
 There are just over 100 elements in the periodic table
From your work in S1 you will know that all substances in the world
are made from elements. There are just over 100 different
elements.
It took a long time to work out how to put all of these elements into
some kind of order. Eventually chemists arranged the elements in a
chart called the Periodic Table. A Russian scientist called Dmitri
Mendeleev was one of the main people who worked out the order and he
has an element named after him as a reward for all of his work.
Dmitri Mendeleev,
Russian Chemist,
1834 - 1907
So the names of the elements have been decided in different ways
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Some are named after scientists
Some are named after planets.
Some are named after continents.
Some are named after the country where they were discovered.
Some are named after the town where they were discovered.
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Lucky for you that you will not need to memorise the names of the
elements because you can always look them up in a data book. Even in
tests.
1. What are all substances in the world made from?
2. Approximately how many elements are there?
3. What is the name of the special chart that all the elements are
arranged in?
4. What was the name of the scientist who did most of the work to
arrange the elements?
5. Dmitri Mendeleev did not win a prize for his work but what did he
get?
6. Make a list to show the different ways that the names of some
elements were decided.
7. Collect an intermediate data book and use it to answer the following
questions
(a) There are two periodic tables in the data book. Which page
would you look at to find all of the elements?
(b) Collect the “naming elements sheet” and complete it using
one of the resources in the list below (you might find more
than one name for some of the spaces).
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An intermediate 1 data book
http://www.rod.beavon.clara.net/elements.htm (or the
printed website sheets)
Success tasks
Write 5 sentences about the Periodic Table, including the
following words.
ELEMENT
PERIODIC TABLE
MENDELEEV
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Finding elements in the periodic table
Learning Intention:
 All the elements in the periodic table are in set positions.
Although you will have a copy of the periodic table in all of your tests,
it can sometimes take a while to find what you are looking for. The
work below should help you get to know your way around the
periodic table.
Complete the following activities.
1. Look at the outline of the Periodic Table shown below.
Each of the letters corresponds to the name of an element. Use the
data book to copy and complete the tables below using a periodic table.
Letter
name of
element
Letter
a
f
b
g
c
h
d
e
i
j
name of
element
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2. In the table below the names of some elements have been given
numbers.
1 aluminium
2 carbon
3 sodium
4 iodine
5 neon
6 lead
7 iron
8 gold
9 neptunium
10 calcium
11 iron
12 selenium
Collect a copy of a “blank periodic table”. Use a periodic table to put
the numbers into the correct positions for the elements in the periodic
table. Number 1 (aluminium) has been done for you.
When you are finished stick your completed table into your jotter.
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The names and symbols of elements
Learning Intention:
 All the elements in the periodic table have their own individual
name and symbol.
 The symbols are either a single capital letter or a capital letter
and a smaller letter.
Each element has a name and symbol. The symbol is a short way of
writing elements.
The symbol is made up of one letter or two letters.
The first letter is always a capital letter and, if there are two letters,
the second is always a small letter,
Phosphorus has the symbol P not p
Calcium has the symbol Ca not CA.
1. Copy and complete the table below to who the names and symbols of
some elements. Use a data book to help you.
Element
Symbol
Element
hydrogen
Symbol
Ag
carbon
Gold
lithium
Platinum
sulphur
U
sodium
F
O
Chlorine
Al
Xe
Mg
Th
K
Mercury
N
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2. Use a data book to help you to copy and complete each of the following
sentences.
a)
The symbol for calcium is ____ and not C because C is the symbol
for ____________ .
b)
The symbol for silicon is ____and not S because S is the symbol
for __________ .
c)
The Latin name for potassium is Kalium and that is why it has the
symbol_____.
d)
The Latin name for sodium is Natrium. It has the symbol _____
and not N because N is the symbol for ________ .
Success task
Research 5 different elements and produce a leaflet about them.
This must include
 Date of discovery
 Appearance
 Properties
 Uses
 Other interesting information
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Classifying Elements
Learning Intentions:
 All the elements in the periodic table can be classified into
metals and non-metals
 The periodic table contains elements which are solids, liquids or
gases
 Some elements in the periodic table can be classified as
radioactive.
Classifying means separating elements into similar categories. Just like
your classes have been worked out by separating S3 into tutor groups.
You may have separated you songs into similar categories on your i-pod or
phone. We can do this to elements in the periodic table too.
Elements can also be classified in various ways:
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Metal or non-metal
Solid, liquid or gas
Radioactive or not
They can also be grouped depending on how reactive they are.
To complete the next piece of work you will need to collect three
different colouring in pencils. Your teacher may also show you some
demonstrations of these elements.
Listen while your teacher tells you about metals and non-metals and
colour in your periodic table.
Listen while your teacher tells you about radioactive elements and colour
in your periodic table.
Listen while your teacher tells you about solids, liquids and gases and
colour in your periodic table.
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Success tasks
Discuss the following questions with your partner and write down the
answer to each question.
1. Explain how you can use a periodic table to work out whether an
element is a metal or a non-metal.
2. Is the element called Germanium a metal or a non-metal?
3. Is the element called Selenium a metal or a non-metal?
4. Are there more metals or non-metals?
5. Will the element called Argon react in the same way as the element
called Xenon? Explain your answer.
6. Copy and complete the sentence below.
Elements that are in the s_______ column of the periodic
table have similar properties.
7. How many elements are liquid?
8. What are the names of the liquid elements?
9. How many elements are gases?
10. Make a list of the names of all of the elements that are gases.
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Further Classifying Elements:
Groups in the Periodic Table
Learning Intentions:
 All the elements in the periodic table can be further classified
in Groups.
 There are 8 groups in the periodic table
 Each group is like a family and all the elements in the group
have similar chemical properties.
We have now found out that the elements can be classified into
different categories. Elements can be either metals or non-metals. They
can also be either solids, liquids or gases. You learned in S1 that the
periodic table is split into families called groups. This helps us to find
elements that have similar properties.
Questions:
1. Look at a copy of the periodic table. How many groups are there in
the periodic table?
2. Ask your teacher to tell you what the large middle section of the
periodic table is called. (This is the block between group 2 and
group 3)
Copy and complete the following table: (Some have been done for you)
Element
Group/Section
Element
Group/Section
Carbon
4
Gold
Nitrogen
Magnesium
2
Lithium
Chlorine
Copper
Transition metal Sulphur
Aluminium
Platinum
Neon
Uranium
Oxygen
Titainium
Calcium
Fluorine
Francium
Silver
Mercury
Einstienium
Boron
3
Plutonium
Transition metal
Krypton
Lead
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Group 1 metals include lithium, sodium and potassium. They are in
the same group because they have similar chemical properties.
Experiment: Reactivity of Group 1 metals in water.
metal
safety screen
water
Metal
Lithium
Sodium
Potassium
what happened in water
Write a heading and copy the table above. Fill it in while you watch your
teacher demonstrate the reactions of the metal in water
Answer the following questions.
1. Do the metals in group 1 have similar chemical properties? How can
you tell this?
2. All of the metals bubbled and fizzed when they were put into the
water. What does this tell you has been made in the reaction?
3. Some of the metals melted in the reaction. What kind of energy was
produced in the reaction?
4. Look at a periodic table and write down what you think would happen if
rubidium was put into water.
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Your teacher will now show you DVD(1) which will reveal more
information about group 7 and group 8 elements.Before you watch the
clips look at questions 5-10 on the next page. After watching the clips
answer all the questions.
5. Group 7 elements have a special name. What is it?
6. How many gases are there in Group 7?
7. Which Group 7 element is the most reactive?
8. Group 8 elements have a special name. What is it?
9. Will the Group 8 element called Argon react in the same way as the
element called Xenon? Explain your answer.
10. Give a common use for Group 8 elements.
11. What liquid can be found in the transition metals?
12. Where will you find gold and silver in the periodic table?
13. Will Aluminium have the same properties as oxygen? Explain your
answer.
14. Copy and complete the sentence below.
Elements that are found in the s_______ group in the
periodic table have similar properties.
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Melting and boiling points
Learning Intentions:
 An elements melting point is the temperature when it turns
from a solid into a liquid.
 An elements boiling point is the temperature when it turns from
a liquid into a gas.
 All the elements in the periodic table have different melting
and boiling points.
The melting point of a substance is the temperature that it needs to
change from a solid into a liquid.
melting
The boiling point of a substance is the temperature that it needs to
change from a liquid into a gas.
boiling
Melting points and boiling points for the elements can be found in the
data book.
Iron has a melting point of 1538C and a boiling point of 2861C
At room temperature (25C) there is not enough heat to make the iron
melt or boil so it will be a solid.
Mercury has a melting point of –39C and a boiling point of 357C. At
room temperature (25C) there is enough heat to make it melt but not
enough to make it boil so it will be a liquid.
Oxygen has a melting point of –219C and a boiling point of –183C. At
room temperature (25C) there is enough heat to make it melt and boil so
it will be a gas.
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Answer the following questions
1. What page in the data book would you look at to find out the melting
and boiling points of the elements?
2. What is the melting point of iron?
3. What is the melting point of magnesium?
4. Which has the higher melting point, silver or tin?
5. What is the boiling point of sulphur?
6. What is the boiling point of helium?
7. Which has the higher boiling point, bromine or mercury?
8. Copy and complete the table below to show whether each of the
elements is a solid, liquid or gas at room temperature (25°C).
Element at
25°C
Melting point
in oC
Boiling point in
o
C
Solid, liquid or
gas at room
temperature
aluminium
chlorine
bromine
silicon
potassium
oxygen
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Success task
Copy the following table
What is the definition of melting point?
What is the definition of boiling point?
I can find this information in the Data
booklet
I am able to work out if an element is a
solid, liquid or gas at room temperature.
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Densities of the elements
Learning Intentions:
 Density is how much something of a set volume weighs.
 Each element has its own density value.
 Densities of different elements can be compared using water.
Density: The definition of density is a measure of a substance’s mass
with a set ‘volume’.
The substances below have been cut to fit the same volume (area).
However they all have a different mass.
Which one do you think has the highest density?
The density of water is 1g/cm3.
Substances which are more dense than water will sink in water, and
substances that are less dense than water will float in water.
The densities of the elements can be found in a data book.
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Answer the following questions
1. Think back to the experiment we did recently with Group 1 metals
and water. Do you think Group 1 metals are more or less dense than
water? Explain your answer.
2. Most people think that all metals sink in water. Copy and complete
the table below to show whether each of the metals will float or
sink in water.
Element
Density in g/cm3
Float or sink in
water
aluminium
magnesium
sodium
silicon
potassium
lithium
Success task
Prepare a spider diagram to summarise what you have found out
about the Periodic Table.
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Atomic Theory: Inside the Atom
Learning Intentions:
 Every atom is made up of 3 subatomic particles called protons,
neutrons and electrons.
 Protons have a mass of 1 a.m.u. and a positive charge.
 Neutrons have a mass of 1 a.m.u. no charge.
 Protons and neutrons can be found in the centre of an atom
called the nucleus.
 Electrons have virtually no mass and a negative charge.
 Electrons are found outside the nucleus.
We already know from our work in S1 that atoms are the building
blocks from which all things are made. They are very small particles
and all elements contain only their own atoms, e.g. Oxygen only contains
oxygen atoms, Iron only contains Iron atoms.
We are now going to find out what an atom is made up of and how
scientists worked it all out. This scientific study of the atom is called
ATOMIC THEORY. This investigates the properties of the small
particles inside the atom (called SUB-ATOMIC PARTICLES).
Your teacher will now show you a DVD(1) on Atomic Theory.
Collect the handout called ‘The Mighty Atom’. Read it carefully and
then answer the following questions. The answers are contained in the
handout. If you finish early, complete question 3 on the handout.
1. List the 4 suggestions about the atom that the Chemist John
Dalton put forward about the atom.
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2. Using Daltons table of Elements name the following elements.
(i)
(ii)
(iii)
(iv)
Next to each name put the modern lettered symbol for each
one.
3. What sub-atomic particle did the Physicist J.J.Thomson discover
in 1897, and what charge does it have on it?
4. What did Rutherford call the centre of an atom where most of the
mass (weight) is?
5. What are the sub-atomic particles called which give the nucleus of
an atom a positive (+) charge?
6. What is the name of the neutral (no charge) particles found in the
nucleus of and atom called? (Clue – Chadwick discovered them)
7. Where did Niels Bohr propose that the negatively charged (-)
electrons are found in the atom?
8. Of the 3 sub-atomic particles which one is the lightest?
9. The mass (weight) of protons, neutrons and electrons are not
measured in grams. What units are used instead?
10.
Copy and complete the following table:
Sub-atomic Particle
Proton
Mass (a.m.u)
Charge on Particle
Electron
Neutron
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Success Task
Heading: Inside an Atom
Copy the diagram and add arrows to identify the protons, neutrons and
electrons. Circle and label the nucleus.
Copy and complete the following sentence:
An atom is neutral (no overall charge) because the number of
positive p _ _ _ _ _ _ is equal to the number of n_ _ _ _ _ _ _
e _ _ _ _ _ _ _ _. Protons and neutrons are found inside the
n_ _ _ _ _ _, e _ _ _ _ _ _ _ are found divided into shells around the
centre of the atom called the n_ _ _ _ _ _.
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Inside the Atom: Atomic and Mass Numbers
Learning Intention:
 The atomic number of an element is the number of protons it
has.
 The mass number of an element is the number of protons plus
neutrons it has.
 An atom is overall neutral as it contains the same number of +
protons and – electrons.
Your teacher will show you a DVD(1) on ATOMIC and MASS
NUMBERS.
Read
The DVD you have just watched should have revealed that knowing the
exact number of protons, neutrons and electrons inside and atom is
very important to scientists. For this reason scientists have simplified
things by introducing atomic numbers and mass numbers of atoms.
 The ATOMIC NUMBER of an atom is equal to the
number of protons inside it.
 The MASS NUMBER of and atom is the sum of the
number of protons plus the number of neutrons.
 An atom has no overall charge because the
number of positive protons equals the number of
negative electrons. Therefore, this must also mean
that in an atom the atomic number must also equal the
number of electrons.
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We now know that the number of protons, neutrons and electrons is
different in each different atom.
Examples:
(i)A Phosphorus atom has,
15 protons, 16 neutrons and 15 electrons
Atomic number = 15
Mass number = 31
(ii)A Sodium atom has,
11 protons, 12 neutrons and 11 electrons
Atomic Number = 11
Mass Number = 23
Answer the following questions
1.
What is the atomic number of an atom equal to?
2. What is the mass number of an atom equal to?
3. For each of the following atoms work out the number of protons,
neutrons and electrons. The first one is done for you.
(i) Boron – Atomic number = 5
Mass number = 6
Protons = 3, Neutrons = (7-3) =4, Electrons = 3
(ii) Nitrogen – Atomic number = 7
Mass number = 15
(iii) Carbon – Atomic number = 6
Mass number = 12
(iv)Bromine – Atomic number = 35
Mass number = 80
4. Fluorine has 9 protons, 10 neutrons and 9 electrons. Write down
its atomic number and mass number?
5. Aluminium has 13 protons, 14 neutrons and 13 electrons. Write
down its atomic number and mass number?
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Nuclear Symbols
A short hand way of writing down the atomic and mass numbers of
elements is:
This is called the nuclear symbol of an element. We can see that a
Helium atom has 2 protons, 2 neutrons and 2 electrons.
The nuclear symbol consists of three parts:
 the symbol of the element,
 the atomic number of the element
 the mass number.
Here is an example of a nuclear symbol:
1. Using the nuclear symbol above write down the number of protons,
neutrons and electron in a lithium atom
2. Using the nuclear symbol above write down the number of protons,
neutrons and electrons in a Titanium atom.
3. Chlorine has 17 protons and 18 neutrons. What is its atomic number
and mass number.
4. Now write down the nuclear symbol for Chlorine.
5. How many electrons does the element Chlorine have?
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Success task
Complete the ‘atomic structure’ sort card activity
The Periodic Table Revisited
Learning intentions:
 All the elements in the periodic table are arranged in order
of atomic number.
 Electrons are arranged into different shells around the
nucleus.
 This is called the ‘Electron arrangement’
 The number of outer electrons in an atom is the same as
its group number.
We have found out that the atomic number of an atom is the number
of protons inside the atom. We also know that the atomic number is
different for each element. This information on differing atomic
numbers between elements is very important. In fact it is so important
that the whole periodic table is listed in order of atomic number.
Your teacher will now show you a periodic table and show you how
the periodic table is arranged in terms of Atomic Number.
We have also found out that the number of electrons is equal to the
number of protons. We also know that these electrons are arranged into
shells, which are found around the nucleus. This information is also very
important to scientists as the number of electrons in the outer most
shell of an atom is the same as the group number in the periodic table.
Your teacher will now show you a periodic table and show you where
to find the electron arrangement within each element.
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Look at the atom of Oxygen below. It has an electron arrangement of 2,6
We can also see that it has 8 protons, 8 neutrons and 8 electrons.
Because it has 6 electrons in its outer shell this means it belongs to
group 6.
Question:
Make a table with three headings showing the atomic number and
electron arrangement of the following elements;
Lithium, carbon, aluminium, neon, phosphorus, oxygen, chlorine and
magnesium.
Success task
Prepare 5 questions about atoms and their structure for the other
groups in the class.
(it is important that you know the answers to these questions)
Swap your answers with the other groups in the class.
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