Get premium membership and access revision papers, questions with answers as well as video lessons.

Chemistry Paper 2 Theory Question Paper

Chemistry Paper 2 Theory

Course:Secondary Level

Exam Year:2001

paper 2 (theory)
time: 2 hours (80 marks)

1. The flow chart below shows the main steps in the extraction of zinc metal and some of its chemical reactions. Study it to answer the questions that follow.

a) Identify the following substances
i) Gas Q
ii) Solid P
iii) Substance W
iv) Gas R
b) Write an equation for the reaction that takes place in the roasting furnace.
c) State the main impurity contained in the zinc obtained.
d) Give two industrial uses of zinc
e) Give one effect that the process can have on the environment.
2) Study the flowchart and answer the questions that follow.
a) Name the type of reaction taking place in steps
D
C
B
F
b) Name the reagents, indicating conditions that could be used for steps
E
F
C
A
c) Identify the organic compound Y by giving its structural formula.
d) Give chemical equations for processes C and F.
3. The diagram below represents a mercury cell that can be used in the industrial manufacture of sodium hydroxide. Study it and answer the questions that follow.
a) i) name
I: the raw material introduced at 2
II: another substance that can be used in the cell instead of graphite.
ii) Identify the by- product that comes out at I
iii) Give
I: one use of sodium hydroxide
II: two reasons why mercury is recycled
b) a current of 100 A was passed through the cell for 5 hours.
ii) Write equations for
I: the reaction that occurred at the mercury cathode
II: the reaction in which sodium hydroxide was produced.
ii) Calculate the mass of sodium hydroxide that was produced.
(Na= 23, H=1, O=16, Faraday+ 96500 coulombs)
4 a) Define the term half life
The graph below represents a radio active decay series for isotope H. study it and answer the questions that follow.
i) Name the type of radiation emitted when the isotope H changes to isotope J.
ii) Write an equation for the nuclear reaction that occurs when isotope J changes to isotope K.
iii) Identify a pair of isotopes of an element in the decay series.

c) What are the particles X and Y in the following changes?
d) the table below gives the rate of decay for a radio active element Y.
No. of days 0 270
Mass (g) 384 48
Calculate the half life of the radio active element Y.
f) State two uses of radio isotopes.
5. A 2 M solution of a fully ionized acid was added in portions to 20 cm3 of 2 M sodium hydroxide. The temperature was recorded after each addition of the acid. Both solutions were initially at room temperature.
The readings obtained were as follows:
Volume of 2 M acid added (cm3) 2 4 6 8 10 12 14
Temperature of the mixture 0C 20.5 23.5 26.0 27.8 27.7 26.5 24.2
a) Plot a graph of the temperature of the mixture against volume of the acid added.
b) Use the graph to determine the room temperature.
c) Why was there a temperature rise when the first portions of acid were added?
d) Give two reasons for the fall in temperature during the later additions of the acid.
e) Determine the volume of 2 M acid required to neutralize 20 cm3 of 2 M sodium hydroxide
f) Calculate the number of moles of sodium hydroxide, which would neutralize one mole of acid.
g) Calculate the molar heat of neutralization for one mole of sodium hydroxide. (SHC of solution= 4.2 J/gK density of water= 1 g/cm3)
6. The table below gives standard electrode potentials for the metals represented by the letters D, E, F and G. study it and answer the questions.
metal Standard electrode potential (V)
D
E
F
G -0.13
+0.85
+0.34
-0.76
a) Which metals can be displaced from a solution of its salt by all the other metals in the table? Give a reason.
b) Metals F and G were connected to form a cell as shown in the diagram below.
i) Write the equations for the reactions that occur at the electrodes F and G.
ii) On the diagram indicate the direction in which the electrons would flow.
iii) What is the function of the salt- Bridge?
c) An electric current was passed through a concentrated solution of copper (II) chloride as shown in the diagram below.
I) Explain what change would be observed in the electrolyte as the experiment progresses.
II) After sometime, test tube H was found to contain a mixture of two gases. Explain this observation.
III) Which of the electrodes is the anode? Explain your answer.
7. Study the flowchart given below and answer the questions that follow.
a) Name the substances X, Y and Z
b) Write a chemical equation for the reaction occurring in stage I.
c) Name 2 impurities removed by the purifier.
d) Giving reasons name the most commonly used catalyst in this process.
e) Write a chemical equation leading to the production of substance Z.
f) Explain why substance Y is absorbed in concentrated sulphuric acid instead of water.
g) Name two uses of sulphuric acid.

Chemistry Paper 2 Theory Question Paper

More Question Papers

Popular Exams