(a) Heat is necessary.
- MnO3 is a weak oxidizing agent
(b)Cl2(g) + H2O(l) ------------> 2HOCl
(c) Chlorine water contain HOCl(aq)/ OCl-
- Which donates oxygen atom to the dye oxidizes/bleaches
sharon kalunda answered the question on March 29, 2019 at 13:07
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During purification of copper by electrolysis, 1.48g of copper were deposited when a current was passed through aqueous copper (II) sulphate for 2 ½ hours. Calculate the amount of current that was passed.(Cu = 63.5; IF = 96500C)
Date posted: March 29, 2019. Answers (1)
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i) 8cm of magnesium ribbon was added to 1M HCl(aq)
(ii) 8cm of magnesium ribbon was added to 0.5M HCl(aq)
Graphs of volume of hydrogen gas evolved against time were plotted as shown below.
a) Which of the graphs was obtained for reaction (i). Explain.
(b) Explain the general shape of the graphs.
Date posted: March 29, 2019. Answers (1)
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(c) Write the equation for the reaction between the compound and potassium metal.
Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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(C=12;O=16)(Solved)
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(C=12;O=16)
Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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(i) How much salt Y would saturate 190g of...(Solved)
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(i) How much salt Y would saturate 190g of water at 1000C.
(ii) 150g of saturated solution of Y at 1000C is cooled to 600C. Calculate the mass of Y that crystallizes out.
Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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a) Crystallization.
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Date posted: March 29, 2019. Answers (1)
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(a) Give the correct order of the apparatus, using the letters only, show the correct arrangement that can be used to prepare and investigate the nature of PH of a sample of onion solution.
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Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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(a) Explain in molecular terms the changes occurring in portions.
(i) AB.
(ii) DE.
(b) What is the significance of portion BC?
Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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(a) Why is heating necessary?
(b) Write the equation of the reaction that occurs at the cathode.
(c) At which electrode does reduction occurs.
Date posted: March 29, 2019. Answers (1)