1. Properties of Iron Vanderbilt Student Volunteers for Science
Spring 2019
Training Presentation

2. Why is the science in this lesson important?
Our body needs certain vitamins and minerals to survive, and iron is an important mineral required for adequate delivery of oxygen to different tissues.
However, iron deficiency is also the most common and widespread nutritional deficiency in the world.
Giving newborns with low birth weights iron supplements helps prevent behavioral and neurological problems later in life.
The importance of iron in diet is still being researched, and new functions of iron are still being discovered!

3. I. Introduction
Learning Goals: To help students identify the key factors that differentiate elements and compounds.
Hand out the periodic tables (in binder).
Ask students: What is the difference between an element, and compound? (Keep the discussion as simple as possible.)
Elements are the building blocks of matter. Show students the models of elements, and compounds (pictured-change)
There are two elements (Fe and O2) and one example of a compound (Fe2O3 or rust). (the differently colored balls represent different elements).
You can take the Fe2O3 out of the bag to show the class, but do not remove the Fe and O2 from their bag.

4. I. Introduction: Elements and Compounds cont.
Compounds are formed by chemical combinations of 2 or more elements – in this case, iron and oxygen.
This lesson looks at iron as
1. An element
2. One of the elements in a compound

5. I. Elements and Compounds cont.
Tell the students to take the 3 bottles out of the bag and look at the labels.
Ask students which containers have the element and which has the compound?
Tell the students:
Every compound has its own properties, which are different from the properties of the elements that make up the compound.
element element compound

6. II. Physical Properties of Iron and Iron Compounds
Learning Goals: To help students characterize elemental iron and iron compounds based on physical properties
Students must NOT open their vials
Tell students to put their magnet on the outside of the iron filings and Iron metal containers and slowly move it up the side and across the vial to detect movement.
Have them repeat this with the iron oxide container.
Emphasize that the physical properties of elemental iron and iron compounds are not the same.
Tell students to record their observations.

7. III. Chemical Properties of Iron – Oxidation (Rusting)
Learning Goals: To assist students in understanding the nature of oxidation, and how it is a chemical property of elements and compounds
Ask students if they know what oxidation is? Oxidation usually occurs when an element or compound combines with oxygen.
What are some things that oxidize? Cut apples, copper pennies, silverware.
Iron is oxidizing when it rusts and turns a reddish color.
Ask students to name things that rust. Anything made of iron, that is left outside
This is a chemical property of iron.
Ask students if they have ever seen iron rust in a few seconds? Probably not
Tell the students they are going to put some chemicals together that will cause rusting in just a few minutes.

8. IIIA. Commercial HotHands Pack
Give a HotHands pack to each group of 3-4 students.
Tell students to observe the hand warmer and read the ingredients on their observation sheet.
Tell the class that the “missing ingredient” that is needed to make the hand warmer warm up is oxygen.
When instructed to do so, tear open the plastic covering, take out the hand warmer, shake it, and put it aside until after you do Part IIIC.

9. IIIB. Experiment: Rusting of Iron Filings
Tell the students that the iron filings are still metallic iron, just in smaller pieces.
Tell students to:
1. Sprinkle iron filings on top of the cotton in each cup (a small scattering is all that is needed).
1Note: the reason for using the cotton is to make the color change due to rusting more obvious.
2. Add a squirt of water on top of the filings in the 1st cup.
3. Add a sprinkle of salt and a squirt of hydrogen peroxide on top of filings in 2nd cup.
4. Observe the 2 cups for one minute and then ask them what differences they can see.

10. IIIB. Rusting of Iron Filings cont.
After 1 minute:
The cotton containing iron and water (cup 1) does not have orange coloring.
The cotton containing the hydrogen peroxide and salt (cup 2) will have some orange color (rust).
Set aside to observe again later.
Ask students which of the 2 cups had the best conditions for rusting?
Cup #2 because the hydrogen peroxide could supply more oxygen than just air or water (as in cup 1) and salt speeds up rusting.
Write the formula for hydrogen peroxide (H2O2) and water (H2O) on the board so they can see that the peroxide has more oxygens.

11. IIIC. Checking the Hand Warmer
Check the hand warmer. The oxygen in air reacted with iron to form iron oxide with the release of heat. Tell students this is an example of an exothermic process.
The VSVS team will cut open a HotHands hand warmer and pour the contents into a jar.
Observe this jar and the jar that contains contents left in open air for 24 hours. Note the difference in colors and tell students this is evidence of a chemical change.

12. IV. Review and Clean-up.
Students can check the cups with iron filings to observe the reactions again.
Review the vocabulary words and the responses to the questions on the Observation Sheet.
The HotHands hand-warmer can be left in the classroom with the teacher or the students, returned to the VSVS lab or kept by the VSVS members.
Return all cups with used iron filings in the plastic trash bag.