8Ba/6
Some useful tests
Name
?
Class
8
B
a
1 Select the correct words from the brackets
to complete the following sentences:
If I blow into limewater it will change from
(clear/cloudy) to
(clear/cloudy). This shows that I breathe out
the gas
(oxygen/carbon dioxide).
limewater
normal air – pink
exhaled air – yellow
air containing less carbon dioxide
than normal air – purple
These tubes all contain hydrogencarbonate indicator.
Hydrogencarbonate indicator can detect the amount of carbon dioxide
in the air.
In normal air it looks
(pink/yellow/purple).
In exhaled air it looks
(pink/yellow/purple) because there is
(more/less) carbon dioxide gas in exhaled air than in normal air.
It looks purple in air containing
normal air.
(more/less) carbon dioxide than
Body temperature can be measured using a
cylinder/thermometer).
Normal body temperature in humans is
(measuring
(25 °C/37 °C/45 °C)
Page 1 of 2
Exploring Science for QCA
Copymaster File 8
81
© Pearson Education Limited 2002
8Ba/6
?
Some useful tests (continued)
2 Pond snails respire like us. They take the oxygen they need from water. The
following experiment was set up.
8
B
a
2 days
1
2
3
1
2
3
= live pond snail
= dead pond snail
After 2 days the snails were removed and hydrogencarbonate indicator was
added to each tube.
a What colour do you think the indicator would go if it was added to the
tubes at the start of the experiment?
b What colour do you think the indicator turned in each tube at the end of
the experiment?
1
2
3
c Maria has suggested doing a similar experiment by placing pond snails in
limewater. Write down what you think about this idea.
S
knowledge, literacy
Page 2 of 2
Exploring Science for QCA
Copymaster File 8
82
© Pearson Education Limited 2002