Science project ideas on how to prevent destructive burning or oxidation.
Prevention of Destructive Burning or Oxidation
We have seen that oxidation is very valuable in giving  us usable energy. Can you name examples of oxidation or burning which are harmful? From what we have learned about burning, we should be able to suggest means by which destructive oxidation may be prevented. What two conditions are always necessary for oxidation? Suggest another which is usually necessary. It is clear that if any one of the necessary conditions is removed, then
burning or oxidation must stop. Our problem then is simply to discover methods by which these conditions necessary for oxidation may be prevented. How Destructive Oxidation may be Prevented by Excluding the Air
Coating iron with a substance which does not rust. What are some of the ways in which air may be kept from substances which are apt to undergo harmful oxidation? How are iron fire escapes kept from rusting? Give other examples of the use of this means. Is a tin pan made entirely of tin? Give proof for your answer. Tin ware is made of thin sheets of iron which, after having been thoroughly cleaned, are dipped into melted tin. Iron also may be prevented from rusting by covering it with a layer of zinc, applied in the same way. This is called galvanized iron and is very generally used for pails, water troughs, and similar articles. It is not used for cooking utensils, as zinc may form poisonous compounds. How is the iron hot water boiler in the kitchen prevented from rusting? It is usually painted with a volatile substance (a substance which evaporates quickly) in which there is powdered aluminum, a metal which is not affected by the air. The volatile liquid disappears, leaving on the boiler a thin layer of powdered aluminum which not only gives the boiler a pleasing appearance but also prevents it from rusting. Iron may also be prevented from rusting by covering it with a layer of nickel, which is put on by the use of electricity (nickel plating). The iron of stove pipes and locomotive boilers is usually protected from rusting by a coating which is produced by passing over the hot iron a mixture of highly heated steam
and carbon dioxide. This coating is an oxide of iron, different from the ordinary oxide of iron, and it protects the iron from further oxidation. Iron, coated in this way, is called Russia iron.
How do fire extinguishers work?  A fire is put out by surrounding the burning material with a gas which will not burn. What happens then to the fire? Some fire extinguishers contain a liquid, carbon tetrachloride, which becomes a non- inflammable gas when it is squirted on the fire. In the fire extinguishers which are inverted just before being used, sulphuric acid falls into a solution of soda. The action of the acid upon the soda produces a large quantity of carbon dioxide which forces out the mixture of water and carbon dioxide. What effect will this have when played upon the burning objects?
Explain the reason for keeping pails of sand in various parts of a garage. Why is water not used for the purpose? Will water mix with gasoline? Smothering a fire Explain why it is advisable to roll a person whose clothing is on fire in a rug or blanket. Is it advisable for a person to start to run if his clothing is on fire? Why? Why are burning draperies pulled down and stamped upon?
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