(a) 2.8
(b) (i) WX2
(ii) Bonds – Ionic bonds
Structure – Giant ionic structure.
maurice.mutuku answered the question on September 5, 2019 at 07:23
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Study the flow chart below and answer the questions that follow.
(a) Give the names of the following.
(i) Solid P
(ii) Solid U
(iii) Solid T
(b) Write the equation for the reaction taking place in Step I.
(c) Write the equation for the reaction between concentrated hydrochloric acid and solid P.
(d) Explain what would happen if hot concentrated sodium hydroxide was used in place of cold dilute sodium
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Date posted: September 5, 2019. Answers (1)
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Date posted: September 5, 2019. Answers (1)
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Determine the change...(Solved)
During electrolysis of aqueous copper (II) sulphate using copper electrodes, a current of 0.2 amperes was passed through the cell for 5 hours.
Determine the change in mass of the cathode that occurred as a result of the electrolysis process
(Cu = 64, IF = 96,500C).
Date posted: September 5, 2019. Answers (1)
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Aqueous copper (II) sulphate was electrolysed using the set up shown below.
(i) When the switch was closed, a gas was produced at electrode B.
Which electrode is the anode?
(ii) Write the half equation for the reaction at electrode B.
(iii) What happens to the PH of the electrolyte above during electrolysis? Explain.
(iv) If carbon electrodes were replaced with copper electrodes in the cell above, write the equations for the reaction that would occur at the anode.
Date posted: September 5, 2019. Answers (1)
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(i) Which element is likely to be hydrogen? Give a reason for your answer?
(ii) What is 
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Date posted: September 5, 2019. Answers (1)
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Date posted: September 5, 2019. Answers (1)
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Date posted: September 5, 2019. Answers (1)
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(i) State the enthalpy changes represented by A,B and C
(ii) What is the relationship between 
Date posted: September 5, 2019. Answers (1)
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A student from Nyeri High School wanted to determine the enthalpy change of combustion when a hydrocarbon with the formula C6H14 was burnt. The following are the results of the experiment done.
Mass of water = 100g
Initial temperature = 18.0ºC
Final temperature = 58.0ºC
Mass of the hydrocarbon burned = 0.43g
Specific heat capacity of water = 4.2Jg-1k-1
(a) Write a balanced equation for the combustion of the hydrocarbon.
(b) (i) Calculate the amount of heat given out in kJ when 0.43g of the hydrocarbon burn in air.
(ii) Calculate the number of moles of the hydrocarbon that were burnt.
(iii) Calculate the molar enthalpy of combustion of the hydrocarbon.
(c) The theoretical value of the heat released when 1 mole of the hydrocarbon is burnt is 4194.7kJ/mol-1 Give two reasons why the value obtained from this experiment is less than the theoretical value.
Date posted: September 4, 2019. Answers (1)
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(i) What name is given to the group of elements to which C and F belong?
(ii) Which letter represents the element that is the least reactive?
(iii) What type of bond is formed when B and E react? Explain.
(iv) Write the formula of the compound formed when D and oxygen gas reacts.
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Date posted: September 4, 2019. Answers (1)
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(ii) Name gas X and state one chemical property of the gas.
Date posted: September 4, 2019. Answers (1)
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(a) Write an equation for the reaction in which copper...(Solved)
During extraction of copper, the ore is first concentrated and roasted to produce copper (I) sulphide.
(a) Write an equation for the reaction in which copper (I) sulphide is produced by roasting the ore in air.
Date posted: September 4, 2019. Answers (1)
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Date posted: September 4, 2019. Answers (1)
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(i) State why vinyl chloride (CH2 = CHCl) undergoes addition polymerization.
(ii) Name the polymer...(Solved)
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(i) State why vinyl chloride (CH2 = CHCl) undergoes addition polymerization.
(ii) Name the polymer formed.
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Date posted: September 4, 2019. Answers (1)
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Date posted: September 4, 2019. Answers (1)
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(a) Determine the molecular formula of gas A (C = 12.0,...(Solved)
The molecular formula mass of gas A is 28 and its empirical formula is CH2.
(a) Determine the molecular formula of gas A (C = 12.0, H = 1.0).
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Date posted: September 4, 2019. Answers (1)
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Date posted: September 4, 2019. Answers (1)
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Study the information in the table below and answer the questions that follow:
A mixture containing 40g salt G and 120g salt Y in 100g of water at 80ºC was cooled to 50ºC.
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Date posted: September 4, 2019. Answers (1)
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Date posted: September 4, 2019. Answers (1)