Name_______________________________________________ Date:_____________________Hour______
The Pyrite Lab
Background Information:
When two elements are mixed together but not chemically combined it forms a class of matter that is called a
mixture. The substances in a mixture may change their physical appearance, but they are still the same substances. They
can also be separated out of the substance by using physical and not chemical means.
If two or more elements are chemically combined they form a class of matter that is called a compound. The
properties of a compound are usually different from the properties of the elements that make up the compound. And
unlike a mixture, the elements that make up a compound can only be separated out by another chemical reaction.
Water (H2O) is an example of a compound. Water is very different from the hydrogen and oxygen gas that combine to
form water.
Problem:
 What differences will you observe between a mixture of iron and sulfur and a compound containing iron and
sulfur?
 Will the properties of iron and sulfur be the same in a mixture and in a compound?
 Can the iron and sulfur be physically separated in a mixture and in a compound?
Procedure:
1. Make observations of sulfur and iron separately. Fill out the Observations (Element Section)
2. Add one scoop of iron and one scoop of sulfur to the cup provided
3. Mix the sulfur and iron together in the cup using the popsicle stick.
4. Making sure the magnet is in the plastic baggie, try to separate out the iron from the sulfur. Fill out the
Observations (Mixture Section)
5. Remove the magnet from the baggie in order to put the iron back into the cup. Remix the sulfur and iron.
6. Return the mixed sulfur and iron to the beaker up front.
7. Watch your teacher’s demonstration. Mrs. Brunner will put the sulfur and iron mixture into a test tube and will
heat it over a bunsen burner.
8. When the entire mixture is glowing bright red, she will drop the test tube into ice water.
9. Observe the pyrite made. Fill out the Observations (Compound Section)
Observations:
Physical Properties of Sulfur (Element)
Color_________
Magnetic? ______ Describe particles ___________________________________________________
Physical Properties of Iron (Element)
Color ________
Magnetic? ______ Describe Particles __________________________________________________
Sulfur and Iron (Mixture)
Have any of the physical properties of the 2 elements changed? _______
Can they be separated by physical means? _______ How? ___________________________________________________
Have the iron and sulfur changed into another substance? _______
7th Grade Science: The Non-Living Earth- Chemistry (Classwork)
Sulfur + Iron after heating (Compound)
Color _______
Magnetic? _______ Describe particles _________________________________________________
Have the physical properties of iron and sulfur changed? ____
Can they be separated by physical means?_______ chemical means? _____
Is this substance still iron and sulfur? _____ What is it? _____________________________________________
What is the chemical formula of this substance? ________ (look at Counting Atoms Notes)
Pyrite Lab Questions
1. Name the two elements and their chemical symbol that were used in this lab.
Draw a Bohr diagram of sulfur.
2. Did the properties of the elements change when they were mixed together? Could they be separated by physical
means? Explain why by discussing mixtures.
3. What kind of substance was formed when you heated the elements in a test tube? Is this an element, mixture or
compound? Explain why and explain the only way the elements could be separated.
4. Circle the reactants and underline the products in the chemical reaction for making iron pyrite. Label the
subscripts and coefficients.
Fe(s) + 2S(s)  FeS2(s)
5. What type of bond is made between Fe and S to make FeS2? How do you know?
6. What type of ion will Sulfur become in order to follow the octet rule?
7.
Describe how you knew there were chemical changes taking place when the elements were heated together.
8. Label the pictures below as sulfur (element), iron/sulfur (mixture), or iron sulfide (compound) based on what is
displayed.
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7th Grade Science: The Non-Living Earth- Chemistry (Classwork)