Making sparklers

Making sparklers is an exciting activity that vividly demonstrates the energy released in chemical reactions.

Carefully weigh the following

10.0 g iron powder

0.5 g magnesium powder

2.0 g aluminium powder

6.0 g potassium chlorate

25 g barium nitrate

Place 6.0 grams of soluble starch in a 100 ml beaker. Add 15 ml of warm water and stir into a thick paste. Add the mixture of the above chemicals to the starch. Role the mixture into a long cylindrical shape or into small spheres. Allow to dry overnight on  bench top.

When dry  use a lighter to ignite it. Keep students at least 5 metres away. Only ignite the mixture outdoors.

The chemicals used are reactive and small hot pieces of metal will shoot into the air. Proper eye protection should be worn.

The nitrates  and chlorates decompose on heating to produce oxygen gas. This oxygen gas ignites the metals and shoots them out.

Write the equations below in the form of a proper balanced chemical equations.

Aluminium and Oxygen gas àAluminium oxide

Al + O2  à Al2O3 (Balance this equation now)

Magnesium and Oxygen gas à Magnesium oxide (MgO)

Iron and oxygen gas à iron oxide (Fe2O3)

Barium nitrate à Barium Oxide (BaO) + Oxygen gas (O2)

It is best to work outdoors. Pile the sparklers on top of each other as shown on the right. Using a match, light one of the spheres and stand back.

A great deal of heat is produced and the reaction quickly accelerates. Students should stand back at least 5 metres from the burning sparklers. Click to see a 120kb video.

Click to see how quickly the same sparkler mixture ignites when in powder form. Why does powder react quicket than the small spheres?

A molten mixture of metal is left after the reaction has ceased. This as close as you will get to creating your own volcanic lava.