SATs - Science Exercise 13 - Materials Levels 5

Materials - Levels 5 - 7

Many foods and drinks are sold in cans. Some cans are made of aluminium and others of tin-plated steel.

drink/ food pH

Pork 7

Peaches 4

orange juice 2

cola 3

When cans were first used over a hundred years ago, it was found that meat such as pork kept for months even in the un-plated steel cans of the time. However, steel cans of peaches bulged, or even burst because of a gas produced inside.

Why were un-plated steel cans no good for keeping peaches?

_____________________________

Which gas caused the cans to bulge?

The list shows part of the reactivity series of metal. (The most reactive is at the top).

Sodium
Magnesium
Aluminium
Zinc
Iron (steel is mostly iron)
Tin
Copper
Gold

Use the list to explain why tin (coated) cans will store fruit better than steel can

Denting a can may crack the layer of tin. Why is it unwise to eat food from damaged/ dented cans?

Lots of modern drinks cans are made from aluminium. This is strange when you consider the reactivity series. Explain why.

The diagrams above show how atoms are arranged inside six substances. Each circle represents an atom and the letter inside is the chemical symbol.

Write down the numbers of the diagrams that show compounds.

State how you know these are compounds.

Give the formulae of diagrams 5 and 6.

_____________________________

Write the names of the elements represented by the following symbols.

Cl _____________

Mg _______________

Na _______________

S _________________

Name the substance shown in diagram 1.

Last modified on: Tuesday, June 9, 1998.