1. Learning Outcomes
I can identify and describe the difference between a Mixture, a Compound, an Element, Atom and a Molecule

2. Draw and label an atom in your jotter.
Elements and Atoms
All elements are made up of very tiny particles called
atoms.
The centre of the atom is called the nucleus. The nucleus
contains particles called protons. Electrons spin round
the nucleus in energy levels.
Q1. What particles are found in the nucleus of an atom?
Q2. What particles are found in the energy levels
surrounding the nucleus?
Draw and label an atom in your jotter.

3. More about Atoms
The atoms of a particular element are all the same as they
all have the same number of protons and electrons. This
number is called the atomic number and it matches the
position of an element in the Periodic Table e.g. hydrogen is
number 1 in the table and all its atoms have 1 proton and 1
electron whereas oxygen is number 8 in the table and all its
atoms all have 8 protons and 8 electrons.
Q3. What number gives the position of an element in the
Periodic Table?
Q4. What does this number tell you about the atoms of that
element?
Q5. Magnesium is number 12 in the Periodic Table. How many
protons and electrons does an atom of magnesium have?

4. Use your periodic table to copy and complete the table
Name of Element
Symbol of Element
Number of Protons
Number of Electrons
carbon C 6
helium He
silicon 17 Fe Au

5. Making Model Molecules
In a model atom kit the following colour code applies.
Copy the atoms into your jotters and colour them
using coloured pencils. Remember to name the atoms.
red for oxygen black for carbon
blue for nitrogen white for hydrogen
green for chlorine
When atoms join together they form molecules. All
the holes in the model atoms must be used up with the
plastic bonds. The other ends of the plastic bonds must
then be joined to other atoms.

6. Making Model Molecules (2)
Q1. What do atoms form when they join together?
Q2. how many holes does an oxygen atom (red
sphere) have? How many bonds will oxygen
form?
Q3. How many holes does a chlorine atom (green
sphere) have? How many bonds will chlorine
Q4. How many holes does a nitrogen atom (blue
sphere) have? How many bonds will nitrogen

7. Molecules of Elements
Join two model atoms together to make the following
molecules and draw a labelled coloured picture of
each one. The first one has been done for you.
A chlorine These examples all show
B oxygen molecules of elements.
C nitrogen We know this because the
D hydrogen molecules contain only
one type of atom.
Q5. How many types of atom are present in a
molecule of an element?

8. Molecules of Compounds
To make models of compounds we use different coloured model atoms joined together e.g. methane is a compound formed between carbon and hydrogen.
The Black sphere represents carbon. The black sphere has 4 holes which means it can form 4 bonds. Hydrogen is represented by the white sphere. Hydrogen atoms can form 1 bond.

9. Molecules of Compounds (2)
Now join your model atoms together to make other
model molecules of compounds like methane. Draw
a labelled coloured diagram of each one in your
jotters.
A hydrogen chloride C nitrogen hydride (ammonia)
B hydrogen oxide (water) D carbon dioxide
Q6. How many types of atom are present in a
compound?

10. Sorting out Elements and Compounds
Put two headings in your jotter: Element and Compound
Look at the molecules below and decide whether they
are compounds or elements. Draw the molecules
under the correct heading.

11. Mixture, Compound, Element, Atom or Molecule?
Look at the diagrams on the next slide. Collect
the diagram sheet and decide whether they show
A mixture
A compound
An element
An atom
A molecule
Stick the completed diagram into your jotter.

12. Mixture, Compound, Element, Atom or Molecule?
A B C D

13. Mixture, Compound, Element, Atom or Molecule?
Try the Power Point test for mixture,
compound, element, atom or molecule?.
Arrange yourselves into groups of Look at
each of the powerpoint pictures and discuss whether
they show:
A mixture
A compound
An element
An atom
A molecule

14. Summary
When two or more elements are joined together during a chemical reaction then a new substance called a compound is formed.
If elements do not react and are not joined together then a mixture is formed.
All elements are made up of tiny particles called atoms.
The nucleus of an atom contains protons and neutrons.

15. Summary (2)
The energy levels surrounding the nucleus contains electrons
The atomic number gives the position of an element in the Periodic Table.
Atoms form molecules when they join together.
Compounds have a slightly different name from the elements from which they were made. The 1st element keeps its name but the 2nd element has some of its letters changed to –ide.