03 Feb Rust prevention
Chemistry tuition classes in Miracle Learning Centre is very useful. If you do not understand chemistry, you must definitely attend the chemistry tuition class at Miracle Learning Centre. Let us learn about rust prevention in this chemistry tuition lesson.
Your chemistry tuition teacher at Miracle Learning Centre will teach you about the rusting of iron. Iron reacts with oxygen and water to form iron(III) hydroxide which is rust. There are many ways to prevent rusting of iron. One way is to coat it with oil. You can also coat it with paint which acts as a barrier for oxygen and water to enter.
Sacrificial protection is coating iron with a more reactive metal like magnesium or zinc. Magnesium is more reactive than iron and hence loses electrons more easily than iron. Hence magnesium will react in preference to iron. This is commonly seen when magnesium is used to protect underground iron pipes. The iron pipes are connected by a wire to a block of magnesium on the surface of the ground. When the magnesium block is used up in the reaction, it will be replaced by a new block of magnesium. Galvanising is coating of zinc on iron.
The student at Miracle Learning Centre asked, ” How does tin protect iron in our canned food? Since tin is less reactive than iron, it cannot be used as a sacrificial metal.”
The chemistry tuition teacher at Miracle Learning Centre replied, ” Tin protects iron only if there is a continuous coating around iron. It acts a barrier to prevent oxygen and water from entering. Once the layer has been scratched, tin no longer protects iron. In fact, iron will react faster than if tin were not around. This is because iron is now the sacrificial metal and reacts in preference to tin.”
Miracle Learning Centre hope you have understood the rust prevention and how it helps you to answer chemistry tuition questions. Do come to Miracle Learning Centre for more chemistry tuition lessons to learn more about rusting and chemistry.