Using Materials Practice Questions

What is meant by corrosion?

An iron gate is left outdoors and rusts.

Name the two substances from the environment that are necessary for iron to rust.

Rusting can be prevented by applying a coating that acts as a barrier.

Give two ways of applying a barrier coating to an iron object.

Bronze is an alloy of copper and one other metal.

Name the other metal in bronze.

Give one use of bronze.

Brass is an alloy of copper and zinc.

Give one use of brass.

The body panels of an aircraft are made from aluminium alloys.

Give one property of aluminium alloys that makes them suitable for this use.

Aluminium is a reactive metal, but aluminium aircraft panels do not corrode away.

Explain why.

Most of the glass used for drinks bottles is soda-lime glass.

Soda-lime glass is made by heating a mixture of sand and two other substances.

Name these two other substances.

Beakers used in school laboratories are made from borosilicate glass, which is made from sand and boron trioxide.

Suggest why borosilicate glass is used instead of soda-lime glass for beakers that are heated with a Bunsen burner.

A porcelain cup is a clay ceramic.

Describe how a porcelain cup is made from wet clay.

Explain why the water in tube A was boiled and then covered with a layer of oil.

Explain how the results in the table show that both air and water are necessary for iron to rust.

Explain, in terms of relative reactivity, how the blocks of zinc protect the steel hull from corroding.

Suggest why the blocks of zinc have to be replaced regularly.

Ship hulls can be coated with paint or coated with a layer of zinc.

Explain why a deep scratch in the paint leads to rusting, but a deep scratch in the zinc coating does not.

Identify which steel is a stainless steel.

Give a reason for your answer.

Use the table.

Steel Q is used to make the blades of chisels.

Explain why steel Q is suitable for this use.

Use the table.

Car body panels are made by pressing flat sheets of steel into curved shapes.

Identify which steel in the table is most suitable for making car body panels and explain your choice.

Low density poly(ethene) (LDPE) and high density poly(ethene) (HDPE) are both made from ethene.

State how the two different forms of poly(ethene) can be produced from the same monomer.

HDPE consists of long unbranched polymer chains. LDPE consists of branched polymer chains.

Explain why HDPE is used for rigid water pipes and LDPE is used for flexible food wrap.

A saucepan handle is made from a thermosetting polymer rather than a thermosoftening polymer.

Explain, in terms of their structures, why a thermosetting polymer does not melt when it is heated but a thermosoftening polymer does.

In the carbon fibre composite, identify:

• the reinforcement
• the matrix.

A racing bicycle frame must be as light as possible and must not break under large forces. Cost is less important for a professional racing team than for a shop selling bicycles to the public.

Evaluate the use of the four materials in the table for making bicycle frames.

Use the table.

A ring is made from 9 carat gold.

Calculate the percentage of gold in this ring.

A bracelet made from 18 carat gold has a mass of $12.0\ \mathrm{g}$.

Calculate the mass of gold in the bracelet.

A gold chain has a total mass of $11.2\ \mathrm{g}$ and contains $7.0\ \mathrm{g}$ of gold.

Determine the number of carats of the gold in this chain.