Redox Rusting And Iron

Question 1

Oxidation and Reduction

Answer 1

Oxidation- A reaction in which a substance gains oxygen or losses hydrogen or losses electrons
Reduction- A reaction in which a substance losses oxygen or gains hydrogen or gains electrons

Question 2

Redox

Answer 2

Reactions which oxidation and reduction occur at the same time

Question 3

Rust is what, and is formed when

Answer 3

Hydrated Iron(III) Oxide - Fe203.xH20
Formed when iron reacts with oxygen and water

Question 4

Test 1- contains water and air, Test 2- contains boiled water with a layer of oil and air, Test 3- Contains Anhydrous Calcium Chloride and air. Does Rust Happen?

Answer 4

Test 1- Yes as water and air both contact the nail
Test 2- No as boiled water contains no dissolved oxygen and the layer of oil stops air entering
Test 3- No as anhydrous calcium chloride is a drying agent so no water

Question 5

How do you prevent rust

Answer 5

Painting (barrier preventing iron and water from reaching the iron)
Oiling (barrier preventing iron and water from reaching the iron)
Plastic Coating (barrier preventing iron and water from reaching the iron)
Metal covering/playing (thin metal covering is applied by electroplating is a barrier preventing iron and water from reaching the iron)
Galvanising(is plating iron with a layer of zinc) (Is a barrier but also protects the iron by sacrificial protection if scratched
Sacrificial Protection: A more reactive metal than iron is attached to the iron, water and air reacts with the more reactive metal

Question 6

Three raw materials in extraction of haemitite

Answer 6

Haematite- Iron(III) Oxide- Fe2O3
Limestone-Calcium Carbonate- CaCO3
Coke-Carbon-C

Question 7

What is the production of the reducing agent

Answer 7

1.Hot air blasted into the furnace, which heats the furnace. Allows coke to burn rapidly forming carbon dioxide. Carbon + Oxygen —>carbon dioxide
2. Reaction above is exothermic, enables more coke to react with carbon dioxide forming Carbon Monoxide. Carbon dioxide + Carbon —> carbon monoxide.

Question 8

What is the reduction of haemitite

Answer 8

The carbon monoxide reduces the iron ore by removing the oxygen. Produces molten iron which sinks and stays molten and also produces carbon dioxide. Iron(III) Oxide + Carbon Monoxide—> Iron + Carbon dioxide

Question 9

What is the removal of acidic impurities

Answer 9

1. Acidic Impurities such as Silicon dioxide(from the sand in the haemitite rock) are present. Limestone added to remove these. When added its thermally decomposed by the heat. Calcium Carbonate –> Calcium Oxide + Carbon dioxide
2. Calcium oxide reacts with silicon dioxide forming calcium silicate(slag). This molten slag floats on the molten iron(at the bottom of the furnace) these are tapped off as liquids separately. Calcium oxide + Silicon dioxide —> Calcium silicate