a) 2NH$_{3(g)}+3CuO_{(s)}\rightarrow 3Cu_{s} + 3H_2O_{(l)}+N_{2(g)}$
b) The contents in the water turned blue. Excess ammonia dissolves in the water forming ammonium hydroxide which is alkaline
johnmulu answered the question on April 20, 2017 at 06:37
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Dry ammonia gas was passed over heated lead (II) oxide and the products passed over anhydrous copper (II) sulphate as shown in the diagram below.
State:
a) Two observations made in the combustion tube
b) The property of ammonia gas in this experiment.
Date posted: April 20, 2017. Answers (1)
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Date posted: April 18, 2017. Answers (1)
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Explain this observation.
Date posted: April 15, 2017. Answers (1)
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a) write the formula of the complex ions in solution Q.
b) Write an equation for the reaction in step IV.
Date posted: April 15, 2017. Answers (1)
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(Solved)
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ii) Name one other substance that can be used in place of sodium nitrate.
iii) What is the purpose of using tap water in the set up above?
Date posted: April 15, 2017. Answers (1)
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Study the flow chart below and answer the questions that follow.
a) name the suitable drying agent for ammonia
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c) Name X.
Date posted: April 15, 2017. Answers (1)
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a) describe how nitrogen gas is formed in the flask.
b) Nitrogen is inert. State one use of the gas based on this property.
Date posted: April 15, 2017. Answers (1)
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Date posted: April 15, 2017. Answers (1)
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ii) Name another substance that can be used instead of potassium nitrate.
iii) Give one use of nitric (V) acid
Date posted: April 15, 2017. Answers (1)
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(Solved)
The flow chart below shows some reactions starting with lead (II) nitrate. Study it and answer the questions that follow.
i) State the condition necessary in step 1.
ii) Identify:
I. Reagent K.
II. Gas Q.
III. Acidic products S and R.
Date posted: April 15, 2017. Answers (1)
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a) Identify gas A
b) State and explain a precaution that must be taken before heating is stopped.
Date posted: April 15, 2017. Answers (1)
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a) Explain why the pH of solution is above 7
b) What is the use of inverted tunnel?
Date posted: April 15, 2017. Answers (1)
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Describe one chemical and one physical method that can be used to identify gas G.
Date posted: April 15, 2017. Answers (1)
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Study the flow chart below and answer the questions that follow.
(i) Name element M.
(ii) Why is it necessary to use excess air in step 4?
(iii) Identify gas Q.
(iv) Write an equation for the reaction in step 7
(v) Give one use of ammonia nitrate.
Date posted: April 15, 2017. Answers (1)
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a) Identify solution V.
b) State the observations which were made in the beaker.
Date posted: April 15, 2017. Answers (1)
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The flow chart below shows the industrial preparation of ammonia and the process used in the manufacture of some ammonium compounds. Study it and answer the questions that follow.
a) Give the name of the:
(i) Process in step 1.
(ii) Reaction that takes place in step 5.
b) State one other source of hydrogen gas apart from natural gas.
c) Explain why it is necessary to compress nitrogen and hydrogen in this process.
d) Write an equation for the reaction which takes place in step 6.
e) Name the catalyst and the reagents used in step 3.
f) Name compound Z 1
g) Give one commercial use of compound Z2
Date posted: April 15, 2017. Answers (1)
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The diagram below represents a set up that was used to obtain dry nitrogen from air. Study it and answer the questions that follow:
(i) Name solid Q.
(ii) What is the purpose of sodium hydroxide?
(iii) Give the name of one impurity present in the nitrogen gas obtained.
(iv) Give a reason why liquid nitrogen is used for storage of semen for artificial insermination
Date posted: April 15, 2017. Answers (1)
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The diagram below shows a set-up that can be used to obtain nitrogen gas in an experiment.
(i) Name liquid L.
(ii) What observation would be made in tube K after heating for some time?
(iii) Write an equation for the reaction that took place in tube K.
iv) At the end of experiment the pH of the water in the beaker was found to be about 10. Explain.
Date posted: April 15, 2017. Answers (1)
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a) Describe how you would obtain a sample of E from a mixture of gases D and E.
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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a) Identify: (i) X (ii) Y
b) State two uses of polyvinylchloride.
Date posted: April 15, 2017. Answers (1)