Download CfE Higher Chemistry Homework 3.5

Higher Chemistry
Unit 3: Chemistry in Society
Homework 3∙5
1.
Which of the following compounds is a raw material in the chemical industry?
A
B
C
D
Ammonia
Calcium carbonate
Hexane
Nitric acid
Answer ______
2.
Which line in the table shows the correct entries for tetrafluoroethene, C2F4?
Answer ______
3.
When two atoms form a non-polar covalent bond, the two atoms must have
A
B
C
D
the same
the same
the same
the same
atomic size
electronegativity
ionisation energy
number of outer electrons?
Answer ______
4.
20 cm3 of ammonia gas reacted with an excess of heated copper(II) oxide.
3CuO
+
2NH3
3Cu
+
3H2O
+
N2
Assuming all measurements were made at 200°C, what would be the volume of gaseous products?
A
B
C
D
10 cm3
20 cm3
30 cm3
40 cm3
Answer ______
Higher Chemistry Homework 3∙5
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5.
20 cm3 of butane is burned in 150 cm3 of oxygen.
C4H10(g)
+
6½O2(g)
4CO2(g)
+
5H2O(g)
What is the total volume of gas present after complete combustion of the butane?
A
B
C
D
80 cm3
100 cm3
180 cm3
200 cm3
Answer ______
6.
In which of the following reactions would an increase in pressure cause the equilibrium position
to move to the left?
Answer ______
7.
If ammonia is added to a solution containing copper(II) ions an equilibrium is set up.
If acid is added to this equilibrium system
A
the intensity of the deep blue colour will increase
B
the equilibrium position will move to the right
C
the concentration of Cu2+(aq) ions will increase
D
the equilibrium position will not be affected.
Answer _____
8.
A catalyst is added to a reaction at equilibrium.
Which of the following does not apply?
A
The rate of the forward reaction increases.
B
The rate of the reverse reaction increases.
C
The position of the equilibrium remains unchanged.
D
The position of the equilibrium shifts to the right.
Answer ______
Higher Chemistry Homework 3∙5
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9.
Atmospheric oxygen, O2(g), dissolves in the Earth’s oceans forming dissolved oxygen, O2(aq),
which is essential for aquatic life.
An equilibrium is established.
(a)
(b)
10.
(i)
What is meant by a reaction at “equilibrium”?
1
(ii)
What would happen to the concentration of dissolved oxygen if the temperature of
the Earth’s oceans increased?
1
A sample of oceanic water was found to contain 0∙010 g of dissolved oxygen.
Calculate the number of moles of dissolved oxygen in the sample.
Which of the following is the best description of a feedstock?
A
A consumer product such as a textile, plastic or detergent.
B
A complex chemical that has been synthesised from small molecules.
C
A mixture of chemicals formed from raw materials.
D
A chemical from which other chemicals can be extracted or synthesised.
Answer ______
11.
1
1
What volume of oxygen (in litres) would be required for the complete combustion of a gaseous
mixture containing 1 litre of carbon monoxide and 3 litres of hydrogen?
(All volumes are measured at the same temperature and pressure.)
A
1
B
2
C
3
D
4
Answer ______
Higher Chemistry Homework 3∙5
1
12.
Chlorine gas can be produced by heating calcium hypochlorite, Ca(OCl)2, in dilute hydrochloric
acid.
Ca(OCl)2(s)
(a)
(b)
13.
+
2HCl(aq)
Ca(OH)2(aq)
2Cl2(g)
Calculate the mass of calcium hypochlorite that would be needed to produce 0∙096 litres of
chlorine gas.
(Take the molar volume of chlorine gas to be 24 litres mol-1.)
2
Calculate the atom economy if chlorine gas is the desired product.
2
What type of bonding and structure is found in a fullerene?
A
Ionic lattice
B
Metallic lattice
C
Covalent molecular
D
Covalent network
Answer ______
14.
+
1
Which of the following compounds has the greatest ionic character?
A
Caesium fluoride
B
Caesium iodide
C
Sodium fluoride
D
Sodium iodide
Answer ______
Higher Chemistry Homework 3∙5
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15.
Diols are compounds widely used in the manufacture of polymers. Ethane-1,2-diol is used to
produce plastic food containers. In industry ethane-1,2-diol is produced by reacting glycerol
with hydrogen.
(a)
(b)
(c)
Excess hydrogen reacts with 27∙6 kg of glycerol to produce 13∙4 kg of ethane-1,2-diol.
Calculate the percentage yield of ethane-1,2-diol.
2
Calculate the atom economy for the production of ethane-1,2-diol from glycerol and
hydrogen.
2
What type of van der Waal’s force is present in both glycerol and ethane-1,2-diol?
1
Higher Chemistry Homework 3∙5
16.
Hydrogen sulfide is a toxic gas with the smell of rotten eggs.
(a)
Hydrogen sulfide gas can be prepared by the reaction of iron(II) sulfide with excess dilute
hydrochloric acid:
(i)
(ii)
(b)
Draw a diagram to show an assembled apparatus that could be used to measure the
volume of H2S gas produced when a sample of iron(II) sulfide reacts with hydrochloric
acid.
Your diagram should be labelled and should show the names of any chemical used.
2
Calculate the mass, in g, of iron(II) sulfide required to produce 79 cm3 of hydrogen
sulfide gas. (Take the molar volume of hydrogen sulfide to be 24 litres mol-1.)
2
Hydrogen sulfide gas produced from iron(II) sulfide is often contaminated with hydrogen
gas and gaseous arsenic compounds.
(i)
Arsenic(III) sulfide is an orange-yellow powder which is insoluble in water.
Below 310°C it can sublime, turning from a solid to a gas.
Name the type of bonding and structure is present in arsenic(III) sulfide.
Higher Chemistry Homework 3∙5
1
16.
(b)
(ii)
To avoid these contaminants, hydrogen sulfide can be made by reacting aluminium
sulfide with water. Hydrogen sulfide and aluminium hydroxide are produced.
Write a balanced chemical equation for the production of hydrogen sulfide from
aluminium sulfide and water.
17.
Iron can be produced by reacting iron(III) oxide with carbon monoxide as shown in the equation.
Fe2O3
18.
2
+
3CO
2Fe +
3CO2
(a)
Calculate the atom economy for the production of iron in reaction.
2
(b)
What is the atom economy of the product of a reaction when there are no by-products?
1
(a)
Write a balanced equation for the complete combustion of ethyne, C2H2.
1
(b)
If 50 cm3 of ethyne is burned completely in 220 cm3 of oxygen, what will be the volume
and composition of the resulting gas mixture?
1
(All volumes are measured under the same conditions of temperature and pressure.)
Total Marks 36
Higher Chemistry Homework 3∙5