i) - Black precipitates are formed
- Hydrogen sulphide reacts with lead (II) ethanoate to form insoluble lead (II) sulphide which is black
ii) -Solution in B turns red
- Hydrogen sulphide burns in air to form sulphur (IV) oxide which dissolves in water to form acidic solution.
johnmulu answered the question on April 20, 2017 at 09:09
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Date posted: April 20, 2017. Answers (1)
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i) Write the equation for the reaction in which sulphur (VI) oxide gas is produced
ii) Why is it necessary to keep the gases pure and dry?
iii) Describe the process that takes place in chamber G
iv) Name the gases that escape into environment
Date posted: April 20, 2017. Answers (1)
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a) Name reagent Z.
b) Describe the process which takes place in step 2
c) Identify the white solid
Date posted: April 20, 2017. Answers (1)
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a) Name the gas produced in the flask
b) give two reasons why no gas was collected in the gas jar
Date posted: April 20, 2017. Answers (1)
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The aparatus shown below was set to prepare and collect hydrogen sulphide gas
a) Name solid C2
b) Give a reason why warm water is used.
c) What observation would be made if hydrogen sulphide gas was bubbled into a solution of lead (II) nitrate?
Date posted: April 20, 2017. Answers (1)
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a) Name (i) Compound T
ii) Gas U
b) Give a chemical test that you could use to identify gas U
Date posted: April 20, 2017. Answers (1)
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Which contaminant was removed by passing the contaminated air through the apparatus Explain
Date posted: April 20, 2017. Answers (1)
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The diagram below represents the extraction of sulphur by Frasch process
a) Name the substance that passes through tube;
I.
II.
b) What is the purpose of hot compressed air in the process?
Date posted: April 20, 2017. Answers (1)
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The table below shows the observations made when aqueous ammonia was added to cations of elements E, F and G until in excess.
i) Select the cation that is likely to be Zn2+
ii) Given that the formula of the cation of element E is E2+, write the ionic equation for the reaction between E2+ (aq) and aqueous ammonia.
Date posted: April 20, 2017. Answers (1)
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i) Identify gas J.
ii) Using oxidation number, show that ammonia is the reducing agent in step (VI)
iii) Write the equation for the reaction that occurs in step (V)
Date posted: April 20, 2017. Answers (1)
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Dry ammonia and dry oxygen were reacted as shown in the diagram below
a) what is the purpose of the glass wool?
b) What products would be formed if red hot platinum was introduced into a mixture of ammonia and oxygen
Date posted: April 20, 2017. Answers (1)
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(Solved)
A student used the set up below to prepare a sample of nitrogen gas
a) State the function of potassium hydroxide in the set up
b) Give a suitable metal M for use in the combustion tube
c) Give a reason why the nitrogen gas obtained is not pure
Date posted: April 20, 2017. Answers (1)
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a) Write an equation for the reaction between ammonia and copper (II) oxide
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Date posted: April 20, 2017. Answers (1)
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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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Record the reading indicated
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Explain this observation.
Date posted: April 15, 2017. Answers (1)
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The scheme below shows some reaction sequence starting with solid N. Study it and answer the questions that follow.
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)
In the laboratory, small quantities of nitric (V) acid can be generated using the following set up. Study it and answer the questions that follow
i) Give the name of substance R.
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
b) Describe one chemical test for ammonia
c) Name X.
Date posted: April 15, 2017. Answers (1)
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The set up below shows how nitrogen gas is prepared in the laboratory.
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)