Experimental chemistry - Chemistry - page 274

● Theory
Papers 21 and 22 are Core theory papers; Papers 31,
32 and 33 are Extended theory papers.
Do not write in this topic. Where necessary copy
drawings, tables or sentences.

d Identify the gas given off in tests (c)(ii).
and (c)(ii) .

[1]

e What conclusions can you draw about
solid E ?

[2]
[Total: 10]
(Cambridge IGCSE Chemistry 0620 Paper 63
Q5 October/November 2011)

Physical
1 The diagram below shows the elements in a period
of the Periodic Table.

30 Three different liquids P , Q and R were analysed.

P was an aqueous solution of sulfuric acid.

The tests on the liquids and some of the
observations are in the following table.

Li Be B C N O F Ne

Complete the observations in the table.

Tests Observations

a (i) Appearance of the liquids P . . . . . . . . . . . . . . . . . . . . [2]

a To which period of the Periodic Table do these
elements belong? [1]
b Answer these questions using only the elements
shown in the diagram. Each element can be used
once, more than once or not at all.

Q colourless, smell of vinegar

R colourless, no smell

(ii) The pH of the liquids was
tested using Universal
indicator paper.

P . . . . . . . . . . . . . . . . . . . . [2]

Q pH 5

Write down the symbol for the element which
(ii) has six electrons in its outer shell.
(ii) is a halogen.
(iii) is a metal which reacts rapidly with cold water.
(iv) has two forms, graphite and diamond.
(v) is in Group II of the Periodic Table.
(vi) makes up about 80% of the air.

R pH 7

b A piece of magnesium ribbon
was added to a little of each
liquid.
The gas given off by liquid P
was tested.

P . . . . . . . . . . . . . . . . . . . . [2]

Q slow effervescence

R no reaction

c To a little of liquid P ,
hydrochloric acid and aqueous
barium chloride were added.

[6]

c Complete the following sentence using words
from the list below.
atoms electrons molecules
neutrons protons

. . . . . . . . . . . . . . . . . . . . . . . [2]

d Liquid R was heated to boiling
in a test-tube. A thermometer
was used to record the
constant temperature of the
vapour produced.

temperature = 100 °C

The ______ of the elements in the Periodic
Table are arranged in order of increasing number
of ______ . [2]
[Total: 9]
(Cambridge IGCSE Chemistry 0620 Paper 21
Q1 November 2010)

e What conclusions can you draw about
liquid Q ? [2]
f Identify liquid R . [1]
[Total: 9]
(Cambridge IGCSE Chemistry 0620 Paper 61
Q5 October/November 2011)

2 About 4000 years ago the Bronze Age started in
Britain. Bronze is an alloy of copper and tin.
a (i) Suggest a reason why a bronze axe was
better than a copper axe. [1]

(ii) Brass is another copper alloy. Name the
other metal in brass. [1]