Download Unit 1B3 - Nat 4 homework 7

Uddingston Grammar School
National 4 Chemistry
Atomic Structure and Bonding
Unit 1 sub-unit b3 Homework 7
1. A technician set up an experiment to investigate electrical conductivity.
Low voltage
power supply
bulb
substance X
SUBSTANCE X
A
molten metal
B
covalent liquid
C
ionic solution
D
ionic solid
E
solid metal
Identify the two experiments in which the bulb would not light.
(2)
2. The grid contains the names of some chemical processes.
A
B
combustion
D
C
neutralisation
E
addition
polymerisation
F
cracking
electrolysis
Identify the process in which a compound is broken down by electricity.
(1)
3. The following apparatus can be used to electrolyse molten sodium chloride in
industry.
(a) State what is meant by electrolysis.
(1)
(b) Why do ionic compounds such, like sodium chloride, conduct electricity when
molten?
(1)
(c) Name the product formed at the positive electrode.
(1)
(d) A small amount of calcium chloride was added to lower the melting point of
sodium chloride. Suggest why this would be an advantage in industry.
(1)
4. A technician set up the following experiment to electrolyse molten lead
iodide.
electrode
(a)
electrode
(i) In the diagram, the technician has left out a piece of apparatus needed to
electrolyse molten lead iodide.
Name the piece of apparatus which has been left out of the circuit.
(1)
(ii) During electrolysis, the lead iodide is broken down into its elements.
Write a word equation for this reaction.
(1)
(b)
(c)
Why do ionic compounds, like lead iodide, not conduct electricity when solid?
(1)
Name the non-metal element which can be used as the electrodes.
(1)
5. Iron can be mixed with other elements to produce steel for different uses.
Chromium is added to make suitable steel to be used in cooking pots. Railway
tracks are made from steel which contains manganese. Titanium is added to make
steel suitable for aircraft parts where tungsen produces steel use to make
hammers.
Present this information in the form of a table
(2)
6. The old names for chemicals are often different from their modern day names.
OLD NAME
MODERN NAME
Glauber’s salts
FORMULA
Na2SO4
Blue vitriol
Copper sulphate
CuSO4
Green vitriol
Iron sulphate
FeSO4
Write the modern name for Glauber’s salts.
(1)
7. The non-metal sulphur reacts with oxygen to produce sulphur dioxide.
Write a word equation for the reaction between sulphur and oxygen.
(1)