Chemistry Reference
In-Depth Information
Metals
●
Additional questions
1
Use the following list of metals to answer the
questions
a
to
i
: iron, calcium, potassium, gold,
aluminium, magnesium, sodium, zinc, platinum,
titanium.
a
Which of the metals is found native?
b
Which of the metals is found in nature as the ore:
(ii)
rock salt?
(ii)
rutile?
c
Which metal has a carbonate found in nature
called chalk?
d
Which of the metals will not react with oxygen
to form an oxide?
e
Which of the metals will react violently with cold
water?
(ii)
Choose one of the metals in your answer to
e
and write a balanced chemical equation for the
reaction which takes place.
g
Which of the metals has a protective oxide
coating on its surface?
h
Which of the metals reacts very slowly with cold
water but extremely vigorously with steam?
i
Which of the metals is used to galvanise iron?
b
Write balanced chemical equations for the
reactions in which:
(ii)
black solid
A
was formed
(ii)
white powder
C
and brown-pink solid
B
were formed
(iii)
colourless solution
D
was formed.
c
The reaction between black solid
A
and magnesium
is a redox reaction. With reference to this reaction,
explain what you understand by this statement.
d
Write anode and cathode reactions for the
processes which take place during the electrolysis
of molten
D
.
e
Suggest a use for:
(ii)
brown-pink solid
B
(ii)
silvery metal
E
(iii)
green gas
F
.
3
Explain the following:
a
metals such as gold and silver occur native in the
Earth's crust
b
the parts of shipwrecks made of iron rust more
slowly in deep water
c
zinc bars are attached to the structure of oil rigs
to prevent them from rusting
d
copper roofs quickly become covered with a
green coating when exposed to the atmosphere
e
recycling metals can save money.
4
Iron is extracted from its ores haematite and
magnetite. Usually it is extracted from haematite
(iron(
iii
) oxide). The ore is mixed with limestone
and coke and reduced to the metal in a blast
furnace. The following is a brief outline of the
reactions involved.
coke
gas
X
iron(
iii
) oxide
2
Copper
↓
heat in air (oxygen)
↓
Black solid
A
↓
heat with powdered magnesium
↓
Brown-pink solid
B +
↓
↓
↓
↓
white powder
C
↓
dilute hydrochloric acid
↓
+
+
+
oxygen
coke
gas
Y
gas
X
gas
Y
iron
→
→
→
↓
gas
X
+
↓
Brown-pink solid
B +
a
Name the gases
X
and
Y
.
b
Give a chemical test to identify gas
X
.
c
Write balanced chemical equations for the
reactions shown above.
d
The added limestone is involved in the following
reactions:
limestone → calcium oxide + gas
X
calcium oxide + silicon(
iv
) oxide → slag
(ii)
Give the chemical names for limestone and slag.
(ii)
Write balanced chemical equations for the
reactions shown above.
colourless solution
D +
water
↓
filter and evaporate filtrate to dryness
↓
Solid
D
↓
electrolysis of molten
D
↓
Silvery metal
E
+ green gas
F
↓
↓
↓
↓
a
Name and give the formulae of the substances
A
to
F
.
