Download Credit Revision Questions Topics 8 – 11 1. (a) Which box contains a

Credit Revision Questions Topics 8 – 11
1.
(a) Which box contains a pair of chemicals that will not react with each other?
(b) Which box(es) contain(s) a pair of chemicals that react to form water?
2.
Vinegar is a dilute solution of ethanoic acid in water.
Karen carried out a titration to find out the concentration of ethanoic acid in
some vinegar.
Rough
titre
1st
titre
2nd
titre
Initial burette
reading/cm3
1∙0
21∙7
11∙7
Final burette
reading/cm3
21∙7
41∙7
31∙9
Volume used/cm3
20∙7
20∙0
20∙2
(a) Karen used data from the table to calculate an average volume of sodium hydroxide
solution.
She used this average volume to calculate the number of moles of sodium hydroxide
needed to neutralise the acid in 25 cm3 of the vinegar.
(i) What average volume of sodium hydroxide should she have used?
(ii) Calculate the number of moles of sodium hydroxide in this average volume.
Show your working clearly.
(b) 1 mole of ethanoic acid reacts with 1 mole of sodium hydroxide.
Calculate the concentration, in mol/l, of ethanoic acid in the vinegar.
Show your working clearly.
3.
The equation for the burning of propane is
C3H8(g)
+
5O2
→
3CO2(g)
+
4H2O(g)
Calculate the mass of water produced when 22g of propane burns.
4.
The overall reaction taking place during the extraction of iron is given by the equation:
Fe2O3
+
3C0
→
2Fe
+
3CO2
Calculate the mass of iron, in tonnes, which is produced from 1600 tonnes of
iron(III) oxide.
Show your working clearly.
5.
Hydrogen sulphide is removed by reacting it with sulphur dioxide.
2H2S +
SO2
→
2H2O
+
3S
Calculate the mass of sulphur produced, in grams, when 34 g of hydrogen sulphide
reacts with sulphur dioxide.
Show your working clearly.
6.
Bones are formed when calcium ions and
phosphate ions combine to form insoluble
calcium phosphate, Ca3(PO4)2.
This reaction can be reproduced in the laboratory
by adding a solution of calcium chloride to a solution
of sodium phosphate.
3Ca2+(aq) + 6C1-(aq) + 6Na+(aq) + 2PO43-(aq) → 6Na+(aq) + 6C1-(aq) + (Ca2+)3(PO43-)2(s)
Circle the spectator ions in the above equation.
7.
The diagram shows a cell which can produce electricity.
(a) What is the purpose of the ion bridge?
(b) Name a tin compound which could be used to make the solution containing
tin ions.
(c) The following cell produces a higher voltage than the cell above.
Suggest a name for metal X.
8.
There are different types of chemical reaction.
Identify the type(s) of reaction represented by the following equation.
Fe(s)
+
Cu2+SO42-(aq)
→
Cu(s)
+
Fe2+SO42-(aq)
9.
Sarah set up the circuit shown below.
In beaker B sulphite ions are converted to sulphate ions:
SO32-(aq)
+
H2O(l)
→
SO42-(aq)
+ 2H+(aq)
+ 2e-
(a) On the diagram, clearly mark the path and the direction of the electron flow.
(b) (i) What term is used to describe the type of chemical reaction taking place
in beaker B?
(ii) Suggest what would happen to the pH in beaker B.
(c) Write the ion-electron equation for the chemical reaction taking place in
beaker A.
10. Some Euro coins are made from a hard-wearing alloy called Nordic Gold.
What is an alloy?
11. Identify the statement(s) which can be applied to iron but not to copper.
A
It displaces tin from a solution of tin chloride.
B
It reacts with cold water.
C
It can be obtained by heating its oxide with carbon.
D
It reacts with dilute hydrochloric acid.
E
It is displaced from a solution of its chloride by zinc.
12. Some metals are found uncombined in the Earth's crust but others have to be
extracted from their ores.
(a) Place the following metals in the correct space in the table.
lead, magnesium, mercury
Metal
Method of Extraction
using heat alone
using heat and carbon
electrolysis of molten compound
(b) Iron is extracted by reacting iron(III) oxide with carbon monoxide.
Name the type of industrial plant where iron is extracted.
13. Siobhan carried out some experiments with four metals (W, X, Y and Z) and some
of their compounds. She made the following observations.
(a) Name the gas formed when metal Y reacts with water.
(b) Suggest names for metals W and Y.
(c) Place the four metals (W, X, Y and Z) in order of reactivity (most
reactive first).
(d) Name the type of chemical reaction which takes place when a metal is
extracted from its oxide.