Topics 3,4,5 - Acids, Metals & Fuels: Making Metals More Useful

Question 1

Why is iron alloyed with carbon and other metals to make it steel?

Answer 1

Steel is stronger than iron and it’s also more corrosion-resistant.

Question 2

Give an example of a smart alloy. What can it be used for, and why is it suitable for this use?

Answer 2

E.g. nitinol. It can be used for glasses frames. It’s good for this use because it will go back to its original shape when it’s heated. If the glasses get bent, they can be easily reshaped.

Question 3

Why are alloys harder than pure metals?

Answer 3

Pure metals are made up of a regular arrangement of identical atoms. These can easily slide over each other. When other elements are added to a pure metal, the different sized atoms upset the layers of pure metal atoms asking it more difficult for them to slide over each other. This makes alloys harder than pure metals.

Question 4

What is meant by the fineness of gold?

Answer 4

Fineness describes the proportion of pure gold in a gold alloy.