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Chemistry Paper 2


The table below gives standard electrode potential for, metals represented by the letters D,E,F and G. Study it and answer the questions that follow.

a) Which metal 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.

13 marks


Study the flow chart below and answer the questions that follow.

a) i) Name process I

ii) Give the conditions necessary for process I to occur

iii) Name compound C.

iv) Name the reagent A.

b) Study the table below and answer the questions that follow.

i) Which of the compounds is a solid at 283.0K. Explain

ii) The compound C3H8O is an alkanol. How does its solubility in water differ from the solubility of C5H12? Explain.

c) Complete combustion of one mole of a hydrocarbon produced four moles of Carbon (IV) Oxide and four moles of water only . i) Write the formula of the hydrocarbon.

ii) Write the equation for the combustion reaction.

d) An organic compound T contains 50% Oxygen;12.5% Hydrogen and 37.5% Carbon. The organic compound has a relative molecular mass of 32. i) Determine the molecular formula of the compound T.

ii) Draw the structural formula of the compound T.

The grid below is part of the periodic table. Use it to answer the questions that follow;[the letters are not the actual symbols of the elements].

ii) Select
I. The element in period three which has the largest atomic radius. Give reason for
your answer

II. A letter which represents a monoatomic gas.

iii) Write an equation to show the action of heat on the nitrate of element M.

b) How does the reactivity of Q with sodium ,compare with that of R with sodium.

c) When 1.5g of L were reacted with water 600cm3 of gas was produced. Determine the relative atomic mass of L[Molar gas Volume=24,000cm3.)

d) Give one use of element S.

13 marks


Butane is a gas at room temperature and pressure. It is used to melt bitumen to apply on roads. a) i) Write an equation for the complete combustion of butane.

ii) Define the term standard enthalpy change of combustion.

The volume of water was 200cm3 and temperature rose from 220c to 700c when one gram of butane was burnt.

i) Calculate the energy produced in kilo joules [specific heat capacity=4.2kjkg-1k-1,density of water =1g/cm3]

ii) Calculate the Molar enthalpy change of combustion of butane.[C=12;H=1]

iii) Find the heating value of butane.

ii) Calculate the enthalpy of formation of butane from the energy cycle diagram

11 marks


1g of magnesium ribbon was reacted with hydrochloric acid at room temperature in order to investigate how the rate of reaction varies with time. The results obtained were recorded as shown below.

a) i) Briefly explain why magnesium ribbon is normally cleaned with sand paper before being put into the acid.

ii) Give a balanced chemical equation for this reaction

b) i) On the grid provided, plot a graph of volume of gas produced against the time taken. Label the graph C.

ii) From your graph determine the rate of production of the gas at 110 seconds.

c) On the same axis sketch the graph you would expect to obtain if:

i) The same mass of powdered magnesium was used instead of magnesium ribbon. Label the graph A.

ii) If the temperature of the solution mixture was reduced from 25.00c to 15.00c. Label the graph B.

d) Determine the mass of magnesium ribbon that remained unreacted in this experiment.[Mg=24,Molar gas volume=24.0dm3 at s.t.p]

11 marks


The set-up of apparatus below was used to prepare and collect dry chlorine gas.

a i) Complete the diagram to show how a dry sample of chlorine gas should be collected.

ii) Write a balanced equation for the reaction above. ______________________________________________________________________________ ____ ______________________________________________________________________________ ____

b. i) State the role of Manganese (iv) oxide in the above reaction. ______________________________________________________________________________ ____ ______________________________________________________________________________ ____

ii) Chlorine can also be prepared by reacting concentrated hydrochloric acid with Potassium Manganate (vii). In this case no heating is required. Explain.

iii) Why is chlorine collected by the method you have shown in the diagram above.(1mk) ______________________________________________________________________________ ____ ______________________________________________________________________________ ____

c. i) Iron(II) chloride reacts with chlorine gas to form Iron(III) chloride. During this reaction 7.1g of Iron (II) Chloride were converted to 9.08g of Iron (III) Chloride.

Calculate the volume of Chlorine gas used.

[Fe=56;Cl=35.5;Molar gas volume=24,000cm3]


ii) State two commercial uses of Chlorine gas. _

12 marks


The diagram below shows a blast furnace used for extraction of iron.

a) Name an iron ore from which iron is extracted .

b) State how high temperatures in region B is maintained. ______________________________________________________________________________ ____ ______________________________________________________________________________ ____

c) Name the reducing agent in the process above. ______________________________________________________________________________ ____ ______________________________________________________________________________ ____

d) Identify;

I) Y____________________________________________________________________

II) Z____________________________________________________________________

e) Explain why it is desirable for compound Y to stay on top of Z. ______________________________________________________________________________

f) Write an equation for formation of Z. (1mk) ______________________________________________________________________________ ____ ______________________________________________________________________________ ____

g) How many kilograms of Iron could be obtained from 240kg of Iron (III) oxide. (Fe=56.0 O=16.0) ______________________________________________________________________________ ____ ______________________________________________________________________________ ____ ______________________________________________________________________________ ____ ______________________________________________________________________________ ____

h) State two aspects of the above process on environment.

11 marks

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