1. The Thermite Process A very violent reaction that liberates vast quantities of heat results in the formation of molten iron

2. Purpose To observe the extremely violent reaction that leads to the formation of iron from its oxide (ore) A regulus is the metallic mass that forms beneath the slag at the bottom of a crucible

3. Demonstration Reaction is very energetic and exothermically so Possibility of explosion if water is present in the thermite mixture Temperatures exceed 4500°F

4. Concepts Single replacement reactions Exothermic reactions Redox reactions

5. Single Replacement Reactions General type of inorganic reaction 2Al (s) +Fe 2 O 3(s) Al 2 O 3(s) +2Fe (l) Oxide anions are transferred during reaction from iron(III)oxide to aluminum Oxidation number of Fe is 3+ in starting material and zero in product Oxidation number of Al is 0 in starting material and 3+ in product Oxidation number of oxygen is taken as 2-

6. Exothermic Reactions Heat flows out of system Surroundings heat up Amount of energy liberated equals -730 kJ/mol where kJ stands for “kilojoules” a unit of energy, and “mol” stands for the quantity of matter known as a “mole”

7. Redox Reactions “Transfer of electrons” reaction Redox means “reduction-oxidation” Al (s) gave its electrons to Fe 2 O 3(s) Al (s) was oxidized Fe 2 O 3(s) was reduced

8. Conclusions Single replacement reaction defined by the transfer of oxide anion from Fe 2 O 3 to Al 2 O 3 in this demonstration Reaction demonstrates concept of heat flow Al (s) gave up electrons so is the reducing agent Fe 2 O 3(s) gained electrons so it the oxidizing agent

9. Comments Applications in welding and military incendiary weapons Discovered by Hans Goldschmidt in 1895 Extremely dangerous reaction that should not be performed by students

10. Quiz 1. Who invented the Thermite Process? 2. What is being oxidized in this reaction? 3. What are two applications of this process? 4. What is being reduced in this reaction? 5. Give a definition of an exothermic process.

11. Answers 1. Hans Goldschmidt 2. Aluminum metal is being oxidized to aluminum oxide 3. Welding and military incendiary weapons are a few applications 4. Iron oxide is being reduced to iron metal 5. Heat flows out of a system and the surrounding heat up