8Fa

1       An atom is:

A       the smallest particle that can exist.

B       a group of particles that are all the same.

C       the smallest particle of a compound that exists under normal conditions.

D       the smallest particle of an element that exists under normal conditions.

2       A molecule is:

A       the smallest particle that can exist.

B       the smallest particle of an element that can exist.

C       two or more atoms chemically joined together.

D       the same as an atom.

3       The number of types of atom in a compound is:

A       only one.

B       one or two.

C       two or more.

D       three or more.

4       How many different elements are there in the compound with the formula NH3?

A       one

B       two

C       three

D       four

8Fb

1       Which of these things does not show that a reaction has occurred?

A       The mixture gets hotter.

B       The substance changes from a liquid to a solid.

C       The mixture changes colour.

D       Bubbles of gas form in the mixture.

2       The substances that you get at the end of a chemical reaction are called:

A       reactants.

B       chemicals.

C       products.

D       gases.

3       Which of these changes is a chemical reaction?

A       Melting some margarine in a pan.

B       Boiling a kettle of water.

C       Frying an egg.

D       Cooling a drink by putting an ice cube in it.

4       Complete this word equation:

          sodium carbonate + copper sulphate ® sodium sulphate + ____________

A       copper sulphate

B       copper oxide

C       sodium carbonate

D       copper carbonate

8Fc

1       A mixture is:

A       just one substance, like pure salt.

B       two or more things mixed together, like nuts and raisins.

C       two things chemically joined together, like flour and sugar in a baked cake.

D       a lot of the same thing put together.

2       Which of these is a mixture?

A       oxygen

B       air

C       sugar

D       common salt

3       Pure water is:

A       water which is clean enough to drink.

B       water which runs off the hills.

C       rain.

D       water with nothing dissolved in it.

4       The taste of a bottle of mineral water depends on:

A       what the bottle is made from.

B       which chemicals dissolved in the water as it passed over the rocks.

C       the colour of the bottle.

D       whether you drink it from the bottle or a glass.

8Fd

1       Orange squash is a mixture because:

A       it is safe to drink.

B       it always contains the same proportions of each ingredient.

C       it has a number of different ingredients which can be in different amounts.

D       it is a single pure substance which cannot be split up.

2       Which list contains the three gases which make up over 99.9% of the air?

A       hydrogen, oxygen, carbon dioxide

B       argon, nitrogen, hydrogen

C       argon, nitrogen, oxygen

D       argon, oxygen, carbon dioxide

3       How can the different gases in the air be separated?

A       fractional distillation

B       crystallisation

C       filtration

D       chromatography

4       How could you separate a mixture of iron and sulphur?

A       filtering

B       using a sieve

C       evaporation

D       using a magnet

8Fe

1       The melting point of a pure substance is:

A       the same as the freezing point.

B       the same as the boiling point.

C       lower than the freezing point.

D       higher than the boiling point.

2       Which row in the table shows the correct freezing and boiling points for water?

3       If you add impurities to a substance, what happens to the melting and boiling points?

4       These graphs show what happens to the temperature when four different substances are heated. Which graph shows a pure substance?