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Form the three inequalities that satisfy the unshaded region in the diagram below.
Date posted:
May 22, 2019
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The diagram below shows acidic and basic oxides fit in a general family of oxides.
a) State the name given to the type of oxides that would be placed in the shaded region.
b) Name two oxides that could be placed on the shaded region.
Date posted:
May 22, 2019
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The solubility of copper (II) sulphate is 55g/100g of water at 75oC and 19g/100g of
water at 15oC. What mass of crystals would be deposited, if 150g of a saturated solution
is cooled from 75oC to 15oC.
Date posted:
May 22, 2019
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A sample of unknown gas Z was shown by analysis to contain sulphur and oxygen.
The gas requires 28.3 seconds to diffuse through an aperture into a vacuum. An
identical amount of oxygen gas passes through the same aperture in 20 seconds.
Determine the molar mass of gas Z. (O=16, S=32).
Date posted:
May 22, 2019
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When small amount of carbon (IV) oxide is passed through lime water, a white
precipitate is formed. When excess carbon (IV) oxide is bubbled through, the white
precipitate dissolves to form a colorless solution.
a) Name the white precipitate.
b) Explain using chemical equations why the white precipitate dissolves in excess of
carbon(IV) oxide.
c) What will happen of the above colorless solution is boiled.
Date posted:
May 22, 2019
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A form four student arranged the apparatus as shown below with the aim of collecting
dry hydrogen gas.
Identify with reasons two mistakes in the above set-up.
Date posted:
May 22, 2019
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Explain five documents used in home trade that are prepared by the buyer.
Date posted:
May 22, 2019
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Outline four ways in which utility of a good is created in production
Date posted:
May 22, 2019
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An experiment was set up to demonstrate the necessity of carbon (IV) oxide for
photosynthesis in a certain green plant as shown below. The plant was first kept
darkness for 48 hours before the experiment.
a), Why was the plant kept in darkness for 48 hours before the start of this experiment.
b), What was the role of sodium hydroxide?
ci)What was the results shown by the leaf in the flask when it was tested for presence of starch after
the set up was exposed to light for a day?.
ii), Give reasons for your answer in (c) I above
d. Suggest a control for this experiment.
e), Name other two limiting factors in this experiment.
Date posted:
May 22, 2019
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State why parabolic reflectors are used in car headlights.
Date posted:
May 22, 2019
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The diagram below shows some components of a light microscope.
a), Name the parts labeled
K –
M –
b), State the functions of
P –
Q –
c) A student was viewing a prepared slide of a plant cell under high power microscope.
The features of the cell were blurred. Which one of the labeled parts of the microscope
would the student use to obtain; A sharper outline of the features
Date posted:
May 22, 2019
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The figure below shows the path of a ray of light through a glass prism. The speed of yellow
light in the prism is 1.88 × 108m/s.
(i) Determine the refractive index of the prism material for the light (speed of light in vacuum, c
= 3.0 × 108m/s.
(ii) Show on the figure, the critical angle, c, and determine its value.
(iii) Given that r = 21.2º, determine the angle θ.
Date posted:
May 22, 2019
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The diagram below shows a phenomenon which occurs during cell division.
a) Identify the stage of cell division in which this phenomenon occurs.
b) State the importance of the phenomenon taking place in the part labeled B.
Date posted:
May 22, 2019
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The diagram below represents a transverse section of a plant part. Study it and answer the questions that
follow.
a)Name the class in which the plant belongs.
b) Give a reason for answer (a) above.
c) State one adaptation for the structures labeled X to their functions.
Date posted:
May 22, 2019
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In an experiment to determine the internal resistance of a cell, the following circuit was used.
It was noted that when S is open, the voltmeter reads 1.5V and when S is closed the voltmeter reads 1.3V and ammeter reads 0.2A.
(i) What is the e.m.f of the cell.
(ii) Determine the lost voltage.
(iii)Find the value of R.
(iv) Find the internal resistance of the cell.
Date posted:
May 22, 2019
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A car accumulator is rated 40Al and is expected to supply a constant current for 120 minutes. Calculate the amount of current delivered.
Date posted:
May 22, 2019
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What are the names of modified leaves enclosing bougainvillea flowers whose function is to
attract insect pollinators?
Date posted:
May 22, 2019
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Equal amounts of crushed Irish potato were placed in equal volumes of hydrogen peroxide solution
at indicated pH. The volume of the gas produced was measured and recorded as shown in the table
below.
(a) Name the gas that was produced.
(b)Account for the difference in the volume of the gas produced in pH 4.0 and pH 9.0
Date posted:
May 22, 2019
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Name the branch of Biology that involves the study of Organisms for the sake of classifying them.
Date posted:
May 22, 2019
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Explain why cooking pots made of aluminium do not corrode easily when exposed to
air.
Date posted:
May 22, 2019
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The flow chart below shows some of the stages in the manufacture of sodium carbonate by the
solvay process. Use it to answer the questions that follow:
(a) Name substance N
(b) Name the process taking place in
(i) Step II
(ii) Step III
(c) Write an equation for the react producing sodium carbonate.
Date posted:
May 22, 2019
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A block and tackle system has 3 pulleys in the upper fixed block and two in the lower movable
block. What load can be lifted by the effort of 200N if the efficiency of the system is 60%?
Date posted:
May 22, 2019
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State two factors that reduce the stability of a vehicle while going round a banked bend.
Date posted:
May 22, 2019
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20cm3 of sodium hydroxide solution containing 8.0g/dm3 were required for complete
neutralization of 0.18g of a dibasic acid H2X.
Calculate the relative molecular mass of the acid.
Date posted:
May 22, 2019
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In an experiment a gas jar containing 70cm3 of chlorine gas was inverted over another
containing 70cm3 of hydrogen sulphide gas. The two gases reacted according to the equation
below to form 80cm3 of hydrogen chloride gas.
(a) Using oxidation number identify the oxidizing agent
(b) Calculate the percentage yield of hydrogen chloride gas
Date posted:
May 22, 2019
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Calculate the volume of chlorine gas in cm3 (measured at s.t.p) that is formed when a current of 0.9 A is passed through a solution of concentrated sodium chloride for 30 minutes.
(Na = 23, Cl = 35.5, Faraday constant = 96500, M.G V = 22.4dm3)
Date posted:
May 22, 2019
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Describe how the mixture of Ammonium chloride, sodium chloride and lead II chloride can be separated if all the components of the mixture are to be recovered.
Date posted:
May 22, 2019
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The diagram below represents an arrangement for a large scale manufacture of ethanol for domestic consumption.
(i) Name the process by which ethanol is obtained from the crude oil.
(ii) Suggest two reasons why water is a coolant in this process.
(iii) Why is it possible to separate ethanol from the mixture by this process.
Date posted:
May 22, 2019
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In an experiment, a few drops of concentrated nitric (IV)acid were added to aqueous Iron (II)
sulphate in a test tube. excess sodium hydroxide solution was then added to the mixture.
(a) State the observations that were made when:
(i) Concentrated nitric (V) acid was added to aqueous Iron (II) sulphate.
(ii) Excess sodium hydroxide was added to the mixture.
(b) Write an ionic equation for the reaction that occurred in a(ii) above.
Date posted:
May 22, 2019
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The diagram below shows a set-up of apparatus used to separate miscible liquids.
(a) Name the parts labelled A and B
(b) State the function of the part labeled A.
(c) State the property of the mixture that makes it suitable to be separated by the
method above.
Date posted:
May 22, 2019