Checkpoint (chemistry)

Look at the information about rock A and B.

Rocks A and B both formed from cooling liquid rock.

What type of rock are A and B?

Which rock is a sedimentary rock?

• D

• E

• F

Rock E contains the remains of organisms that lived millions of years ago.

What word is used to describe these remains?

Look at the diagram of the Sun and the Earth.

(a) Write down the name of path X.

The Earth turns on its own axis.

How many hours does it take the Earth to complete one rotation?

• 1 hour

• 24 hours

• 365 days

• 12 hours

The sun is .......................................

• an absorber of light

• a reflector of light

• a refractor of light

• a source of light

A planet is seen because light is .............................

• absorbed by its surface

• emitted by its surface

• reflected by its surface

• refracted by its surface

The reaction between hydrochloric acid and sodium carbonate is an example of

neutralisation.

This neutralisation reaction forms a salt, a gas and a colourless liquid.

The three products of this reaction are ................

• sodium carbonate, hydrogen, water

• sodium, hydrogen, water

• sodium chloride, carbon dioxide, water

• carbon, sodium chloride, hydrogen

How many electrons are in the atom?

• 4

• 5

• 8

• 12

How many neutrons are in the atom?

• 4

• 5

• 9

• 13