i) Liquid L is water
ii) Black copper (II) oxide changes to red brown.
iii) 2NH3(g) + 3CuO(s) $\rightarrow$ 3Cu(s) + N2(g) + 3H2O(l)
iv) The excess ammonia from the reaction dissolves in the water in the beaker to form ammonium hydroxide
which is a weak alkali
johnmulu answered the question on April 15, 2017 at 07:09
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b) Suggest a possible identify of gas D. Give a reason for your answer.
Date posted: April 15, 2017. Answers (1)
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Date posted: April 13, 2017. Answers (1)
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Given that the mass of the solid is 567 g, determine the density of the solid in gcm-3
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Date posted: April 13, 2017. Answers (1)
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Date posted: April 12, 2017. Answers (1)
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Date posted: April 12, 2017. Answers (1)
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Date posted: April 12, 2017. Answers (1)
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Date posted: April 12, 2017. Answers (1)
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Date posted: April 12, 2017. Answers (1)
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(i) S is higher than that of R;
(ii) V is lower than of U.
b) How does the reactivity of W with chlorine compare with that of R with chlorine? Explain.
c) Write an equation for the reaction between T and excess oxygen.
d) Give one use element V.
Date posted: April 12, 2017. Answers (1)
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(The letters are not the symbols of the elements)
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Use the information in the table below to answer the questions that follow.
(The letters are not the symbols of the elements)
Identify a letter which represents an element in the table that could be calcium, carbon or sulphur. Give a reason in each case.
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Date posted: April 12, 2017. Answers (1)
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Date posted: April 12, 2017. Answers (1)
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Use the information in the table below to answer the questions that follow. The letters do not represent the actual symbols of the elements.
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i) S is higher than that of R;
ii) V is lower than that of U.
b) How does the reactivity of W with chlorine compare with that of R with chlorine? Explain
c) Write an equation for the reaction between T and excess oxygen.
d) Give one use of element V.
Date posted: April 12, 2017. Answers (1)
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i) Select the element in period three which has the shorter atomic radius. Give a reason for your answer
ii) Element F has the electronic structure, 2.8.18.4. On the chart above, indicate the position of element F.
iii) State one use of the elements of which E is a member.
iv) Write an equation to show the action of heat on the nitrate of element C.
Date posted: April 12, 2017. Answers (1)
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b) State two industrial uses of hydrogen gas
Date posted: April 12, 2017. Answers (1)
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Date posted: April 12, 2017. Answers (1)
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b) Using kinetic theory, explain the relationship shown in the graph.
Date posted: April 12, 2017. Answers (1)
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The graph below shows the behavior of a fixed mass of a gas at constant temperature.
a) What is the relationship between the volume and the pressure of the gas?
b) 3 litres of oxygen gas at one atmosphere pressure were compressed to two atmospheres at constant temperature. Calculate the volume occupied by the oxygen gas
Date posted: April 12, 2017. Answers (1)