Name _________________________________________
Date ________________
Elements, compounds and mixtures practical
What are the differences between iron and sulphur?
Safety:
Hazard – what
poses the risk
Risk – how it could harm you
Precaution – how you will minimise
the risk
Iron
Sulphur
Iron Sulfide
Glass – e.g. test
tube
Fire – Bunsen
burner
Wear eye protection
Test 1: Observation
Apparatus








test tubes
test tube rack
one small test tube (ignition tube)
ignition tube holder
Bunsen burner
mineral wool
cloth or rag
pestle or hammer







309
a magnet
eye protection
iron filings
sulphur powder
a mixture of iron and sulphur
heatproof mat
tongs
Method
A Look at iron, sulphur, and the mixture. Observe the differences between them. Write your
observations in the table.
Recording your results
Substance
Description
grey solid powder
iron
sulphur
Yellow solid powder
iron and sulphur mixture
Grey solid powder
Test 2: Floating and sinking
Method
B Collect three test tubes and fill each one about half full with water.
C Put a spatula of iron into tube 1. Put a spatula of sulphur into tube 2, and a spatula of the mixture into
tube 3. Write your observations in the table.
Recording your results
Substance
iron
sulphur
Iron and sulphur mixture
Float or sink?
Sink
Float
Some of it floated but some sank
Test 3: Magnetism test
Method
D Collect three dry test tubes. Put a spatula of iron into tube 1. Put a spatula of sulphur into
tube 2, and a spatula of the mixture into tube 3.
E Bring a magnet up to each tube.
310
Recording your results
Substance
Magnetic or non-magnetic?
iron
Magnetic
sulphur
Non-magnetic
iron and sulphur mixture
The iron in the mixture was magnetic but the sulphur was not.
Test 4: Making a compound of iron and
sulphur
Wear eye protection
I
Method
F Put a small amount of the iron and
sulphur mixture into a small test tube
(ignition tube).
G Put a small piece of mineral wool in the
end of the tube to stop fumes escaping.
H Heat the tube in a Bunsen flame until
you see a red glow inside the tube.
Take the tube out of the flame, and when
the reaction has finished leave the tube on
a heatproof mat to cool.
J Wrap the tube in a cloth or rag and break
the glass with a pestle or hammer.
K Use tongs to pick out the pieces of iron
sulphide. Carefully place the broken glass
in the broken glass bin.
L Try tests 1 to 3 on the iron sulphide and
write your results in the table.
Recording your results
Test
appearance
Result for iron sulphide
Gray
float or sink?
Sink
magnetic or not?
Non-magnetic
Considering your results/conclusions
1
The compound that you have made is different from the elements. How can you tell? Write down
two ways.
We can see that a change has occurred because there was a red glow, and the result compound
did not have the same traits as the ingredients.
2. Explain what these changes in properties tell you.
These changes show us that the result was not a mixture of iron and Sulphur but was instead a compound.
3. Complete this word equation for the reaction
iron + sulphur  iron sulphide
311
4. Can you draw the atoms of each substance (you can use any shape / colour to differentiate between
the atoms).
Iron
Sulphur
Iron Sulphur mixture
Iron sulphide
Questions:
1. If your teacher had made iron sulfide by reacting 5.6 g of iron and 3.2 g of
sulfur, how much iron sulfide should have been formed? Explain your answer
using scientific terminology.
There should have been 5.6g + 3.2g of iron sulphide, which is 8.8g. This is
due to the law of conservation of mass, since we kept the test tube closed,
nothing should have escaped, meaning the mass should have stayed the
same.
2. Make a chemical equation for the word equation above:
Fe + S -> FeS
Extension:
1. Explain the difference between a chemical & a physical change (use your device to
research if necessary).
A chemical change is a change that happens through a reaction and is not easily undone. There is
usually some energy given out, whether through the form of heat or through light. Physical
changes are changes such as changes in state and can be undone through physical means such
as melting or freezing.
2. Balance the chemical equation you made in Q2 & add state symbols.
Fe (s) + S (s) -> FeS (s)
I CAN...
312