F2 IS QZ 03 ans

7.2AB

Word Translation (9 marks)

i    Write down the English terms of the following Chinese terms:

	Chinese term	English term
1	發生反應	React
2	燃料	Fuel
3	氧	Oxygen
4	火三角	Fire triangle
5	必須條件	Necessary condition
6	燃料	Fuel
7	氧	Oxygen
8	高溫	High temperature
9	熄滅	Go out

Fill in the Blanks (16 marks)

1      Burning is a chemical process involving fuel and oxygen.

2      When fuels burn in air, they react with oxygen and produce carbon dioxide

and water. Light / heat energy and heat / light energy are given out.

3      The word equation of burning is:

                Fuel + oxygen --------------------------------------------à carbon dioxide + water + energy

4      Fuel, oxygen and a sufficiently high temperature are necessary conditions of

burning. They form the fire triangle. If any one of them is removed, the

fire will go out.

5      When a fire breaks out, we should:

- keep calm;

- leave the flat using stairway and must not use the lift;

- call the Fire Services Department by dialing ‘999’ when you are safe.

Challenging Questions (Bonus 2 marks)

How can we test for the products of burning? Describe the test results.

We can use hydrogencarbonate indicator (lime water) to test for carbon dioxide. The colour changes from red to yellow (changes from colourless to milky).

We can use dry cobalt chloride paper to test for water. The colour changes from blue to pink.