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The chart below shows some of the chemical needed for the production of ammonia gas, nitric
acid and ammonia sulphate in the industry.
(a) Name the chemical that should be in chambers 1,2, 4, 6, 8 and 9
b) State three conditions required to convert the chemical substance in chamber 3 to
SO3(g).
c) Write balanced equations with conditions where necessary for the reactions that
produces chemical substances in chambers:-
Date posted:
May 16, 2019
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The table below shows the atomic numbers of some elements represented by letter J to Q ( letters
not their actual symbols). Study and answer the questions that follow.
a) Write the electronic configuration of
(i) M
(ii) P2+
b) Write the formula of the compound formed when L combines with N
c) How would reactivities of element N and P with chlorine compare? Explain.
d) Element N combines with oxygen to from an oxide. Using dots (.) and crosses(x) to
represent the outermost electrons, show how the two elements combine.
e) Select the most reactive metal and non-metal and give reason for your answer.
f) State one physical and one chemical property that elements J and Q have in common
g) What name is given to the group of elements to which element M belong?
h) (i) Element K consists of two isotopes with relative abundances 75% and 25% and
mass number 35 and 37 respectively find the relative atomic mass of K.
(ii) Why is the relative atomic mass of K not a whole number?
Date posted:
May 13, 2019
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The table below shows solubilities of two salts M and N at different temperatures. Study it and
answer the questions that follow.
A mixture of 55g of salt M in 100g of water and 30g of salt N in 100g of water were cooled from 90oC to 30oC . Calculate the mass of salt that crystallize out.
Date posted:
May 13, 2019
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The diagram below shows a Bunsen burner when in use
Which of the labeled parts is used for heating? Give a reason
Date posted:
May 13, 2019
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During the extraction of lead from its ores one of the main ore used is Galena
(i) Write an equation for the reaction in roasting furnace.
(ii) Name gas
(iii) State one use of lead metal.
Date posted:
May 13, 2019
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Study the scheme below and use it to answer the questions that follows.
Write down the formulae of two possible anions present in salt solution P.
Date posted:
May 13, 2019
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During a displacement reaction, excess iron powder was added to 25cm3 of 0.5 M copper (II) sulphate solutions. The temperature rose from 18.5oC to 33.0oC. Calculate the molar enthalpy of displacement of copper in copper (II) sulphate solution (Specific heat capacity is 4.2 Jg-1K-1, Density of the solution = 1.0g/cm3)
Date posted:
May 13, 2019
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Describe how you would prepare crystals of sodium nitrate starting with 200cm3 of 2M
sodium hydroxide.
Date posted:
May 13, 2019
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The diagram below shows a set –up for preparation of hydrogen chloride gas.
Write the equation for the reaction that produces hydrogen chloride gas.
Date posted:
May 13, 2019
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The following table gives the melting points of oxides of elements in period 3. Study it and
answer the questions that follow:-
(i) Explain the difference in melting points of MgO and P4O10
(ii) Name the compound in the above table that will dissolve both in dilute
hydrochloride acid and dilute sodium hydroxide.
Date posted:
May 13, 2019
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36cm3 of a solution of potassium hydroxide requires 25cm3 of 0.5M sulphuric acid to
neutralize it.Calculate the concentration of alkali in g/dm3
Date posted:
May 13, 2019
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Draw the structural formula of organic compound with the formula C5H10O2 giving its name.
Date posted:
May 13, 2019
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The diagram below represents set-up that can be used to prepare and collect oxygen gas
a) Name solid P
b) What property of oxygen makes it possible for its collection as indicated by the
diagram.
c) Explain why it is important not to collect any gas for the first few seconds of the
experiment.
Date posted:
May 13, 2019
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Study the flow chart below and answer the questions that follow.
a) Identify N and P
b) What name is given to the type of halogenation/Chlorination reaction in step 2
Date posted:
May 13, 2019
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During the electrolysis of dilute sulphuric (VI) acid the volume of hydrogen gas collected is twice
the volume of oxygen gas. Using half equations justify the above statement.
Date posted:
May 13, 2019
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Under certain conditions ,methane reacts with steam to form carbon (II) oxide and hydrogen only. Calculate the total volume of the gas that can be formed when 100cm3 of steam reacts completely with methane.
Calculate the enthalpy change of the reaction.
Date posted:
May 13, 2019
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Classify the following processes as either chemical or physical.
Date posted:
May 13, 2019
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The equation for dissolution of bismuth(III) chloride in water is
Explain the effect on the position of equilibrium if sodium hydroxide solution is added to the mixture at equilibrium.
Date posted:
May 13, 2019
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State the Lechateiler’s principle.
Date posted:
May 13, 2019
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Using a suitable equation explain why it is not advisable to use hardwater in hot water
systems.
Date posted:
May 13, 2019
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The catalytic oxidation of ammonia gas is done as per the set up below.
a) Name the catalyst used in the above reaction.
b) After sometime, brown fumes are formed in the flask. Explain briefly how this
observation occurs.
c) Why does the metal catalyst stay red hot for some time?
Date posted:
May 13, 2019
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Below is a table of 1st ionization energies for elements A,B,C, and D which are metals.
a) What is meant by 1st ionization energy?
b) With an explanation, arrange the elements in order of increasing reactivities.
Date posted:
May 13, 2019
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Hydrogen gas is one of the lightest gas known but has not lived to its expectation to be used inObservation balloons. Explain
Date posted:
May 13, 2019
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Describe how you would prepare a sample of iron(II)carbonate,starting with iron metal and dilute hydrochloric acid.
Date posted:
May 13, 2019
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When 1.15g of R were reacted with water, 600cm3 of gas was produced.
Determine the relative atomic mass of R. (Molar gas volume = 24 000 cm3).
Date posted:
May 7, 2019
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Draw and name the isomers of pentane
Date posted:
May 7, 2019
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60 cm3 of oxygen gas diffused through a porous partition in 50
seconds. How long would it take 60cm3 of sulphur (IV) oxide gas to diffuse
through the same partition under the same conditions? (S = 32.0, 0 = 16.0)
Date posted:
May 7, 2019
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When 8.53g of sodium nitrate were heated in an open test-tube, the
mass of oxygen gas produced was 0.83 g . Given the equation of the
reaction as 2NaNO 3 (s) -> 2NaNO 2 (s) + O 2 (g)
Calculate the percentage of sodium nitrate that was converted to sodium
nitrite. (Na = 23.0, N = 14.0, O = 16.0)
Date posted:
May 7, 2019
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A label on a bottle of hydrochloric acid has the following information: Density 1.134g/cm^3,percentage purity 37%. Determine the molarity of the solution
Date posted:
May 1, 2019
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Explain the Reaction of ammonia with oxygen.
Date posted:
April 30, 2019