Amy Sass

Magnesium Metal Ribbon

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Concept: Chemical Reactions. The property displayed in this experiment uses magnesium metal to display what happens to metal when it reacts with oxygen gas, that is found in the air around us.

Materials:

strip of magnesium metal ribbon - 4 inches long

lighter

Directions:

1. Hold the piece of magnesium metal ribbon in a pair of tongs.

2. Take the lighter and hold the magnesium metal ribbon in the hottest part of the flame.

3. It will soon catch fire and emit a very bright light.

4. CAUTION DO NOT LOOK DIRECTLY AT THE BRIGHT LIGHT. Briefly gaze at the light out of the corner of your eye.

Introduction:

How many of you like the 4th of July, raise your hands. Is fireworks your favorite part of the holiday? Well, it is my favorite part. Remember that you should not play with fireworks unless an adult is with you. Well boys and girls I have a surprise for you, letís shut off the lights.

Explanation:

When magnesium is in its metal form it will burn very easily in air. However, in order to start the reaction (the burning) the magnesium metal needs a source of energy. The flame provides a source of heat so that the magnesium metal atoms can overcome their activation energy. Activation energy is the minimum energy required in order for a chemical reaction to proceed. When the magnesium metal burns it reacts with oxygen found in the air to form Magnesium Oxide, which is a compound. A compound is a material in which atoms of different elements are bonded to one another. Oxygen and magnesium come together in a chemical reaction to form this compound. After it burns, it forms a white powder of the magnesium oxide. Magnesium gives up two electrons to oxygen atoms to form this powdery product. This is an exothermic reaction. An exothermic reaction is a term that describes a chemical reaction in which there is a net release of energy.

2 Mg + O2 -----> 2 MgO + energy

Safety Precautions:

Wear goggles.

Do not let children do this.

Do not look directly at the light emitted from the metal.

Make sure you hold the metal securely with the tongs.

Keep away from combustible materials.

Waste Disposal:

Throw the powder in the garbage.

Reference:

Shakhashiri, Bassam Z. "Chemical Demonstrations", U. Wisconsin Press, 1983,Vol. 1, p.38.