(i) Heat
(ii) PbBr2 melts. Molten PbBr2 contains mobile ions which conduct electric current.
maurice.mutuku answered the question on September 4, 2019 at 07:10
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Determine the oxidation number of:
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(ii) Chromium in 
Date posted: September 4, 2019. Answers (1)
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(iii) Write an equation for the reaction which occurs in Step II.
Date posted: September 4, 2019. Answers (1)
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Mass of...(Solved)
The following results were obtained in an experiment to determine the heat of neutralization of 50cm3 2M hydrochloric acid and 50cm3 2M sodium hydroxide.
Mass of plastic cup = 45.1g
Initial temperature of acid = 27.00C
Initial temperature of alkali = 23.00C
Mass of plastic cup + HCl + NaOH = 145.1g
Temperature of the mixture of acid and alkali = 38.50C
(a) Define heat of neutralization
(b) Write an ionic equation for the neutralization of hydrochloric acid and sodium hydroxide.
(i) The amount of heat produced during the experiment
(Specific heat capacity of solution = 4.2jg-1k-1, density of solution = 1gcm3)
(ii) Molar heat of neutralization for the reaction.
(c) Explain why the molar heat of neutralization of NaOH and Ethanoic acid of equal volume and molarity would be less than the value obtained in C (ii) above.
(d) Write down the thermochemical equation for reaction between NaOH and dilute hydrochloric acid
above
(e) Draw an energy level diagram for the neutralization reaction in (d) above.
Date posted: September 4, 2019. Answers (1)
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Study it and answer the questions that follow.(Solved)
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Study it and answer the questions that follow.
(i) Write an equation for the reaction that produce gas F.
(ii) Describe how gas G can be identified
(iii) Why is the concentration of the acid expected to increase during electrolysis.
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(ii) Select two half cells when combined produce the highest potential difference and determine the electromotive force.
(iii) Which element is likely to be hydrogen? Give a reason
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Date posted: September 4, 2019. Answers (1)
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(a) Write the chemical formula of the chief ore.
(b) Name the possible impurities present in the ore.
(c) Why is it necessary for the ore to be converted into powder form?
(d) Identify process X and state it‟s significance
(e) Write equations for the reaction taking place in the
I. Roasting furnace
II. Formation of substance B
It is not advisable to use lead pipes in transporting drinking water.
Explain why.
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Date posted: September 4, 2019. Answers (1)
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(a) Draw the structural formula and names of the following compounds.
(b) Write the name of the processes that leads to the formation of substances A and F.
(c) Name the type of reaction and conditions required for the formation Step 1
(d) If the relative molecular mass of compound X is 84000 units, determine the value of n (C = 12, H = 1)
(e) Write an equation that leads to the formation of substance E.
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Date posted: September 3, 2019. Answers (1)
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(i) Name the piece of apparatus labelled B.
(ii) What is the purpose of the thermometer in the set up?
(iii) At what point of apparatus B should the tap water be connected. Explain.
(iv) Name the part labelled A and state its function
(v) Which liquid was collected first? Explain
(vi) What is the name given to the above method of separating mixtures?
(vii) What property of the components of the mixture makes it possible for the components to be separated by the method?
(viii) State two applications of the above method of separation.
(b) A form two student was supplied with a liquid suspected to be water.
(i) Describe one chemical test that would be carried out to show that the liquid was water.
(ii) How would it have been proved that the liquid is pure water?
Date posted: September 3, 2019. Answers (1)
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(i) Give the letters representing atoms that can form a singly-charged anion.
(ii) Identify the most electromagnetic element in the grid. Explain.
(iii) Identify the strongest reducing agent.
(iv) Write the formula of the most stable compound formed when J and K react
(v) Give the name of the type of bond in the compound formed in (iv) above.
(vi) Give the chemical family name of L and M.
(vii) Write the ionic equation for the reaction in which gas L is bubbled through a solution with ions of M.
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Date posted: September 3, 2019. Answers (1)
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Explain how the following would affect the yield of hydrogen iodide.
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Date posted: September 3, 2019. Answers (1)
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(a) Write a chemical equation for the reaction...(Solved)
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(a) Write an equation for...(Solved)
In an experiment, excess magnesium ribbons were immersed in ethanoic acid and the gas evolved was measured at 10 seconds intervals.
(a) Write an equation for the reaction between Ethanoic acid and magnesium ribbon.
(b) Sketch a curve of volume of gas evolved against time for the above reaction.
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(a) Suggest why the student did not collect hydrogen gas.
(b) In a separate experiment the student reacted iron and hydrochloric acid to prepare hydrogen gas.
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(ii) The hydrogen gas produced was found to have a foul smell. Suggest an explanation for this.
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C3H7COOC2H5
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(b) Name the compounds used to prepare the above compound.
(c) What is the identifying physical property of...(Solved)
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C3H7COOC2H5
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(a) Write the formula of the anion present in solid N.
(b) Solid N in the flow chart above burns in air with a red flame. Identify the
(i) Cation present in solid N
(ii) Metal oxide L
Date posted: September 3, 2019. Answers (1)