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Chemistry Form 3 Sulphur and its Compounds Questions and Answers

In this session, we are going to solve several questions on Sulphur and its compounds.

Lessons (34)

• 1.    The diagram below represents the extraction of sulphur by Frasch process (a) Name the substance that passes through tube; (b) What is the purpose of hot compressed air in the process?
  1m 56s

• 2.    State what would be observed when dilute hydrochloric acid is added to the products formed when a mixture of iron fillings and sulphur is heated.
  2m 53s

• 3.    A sample of air contaminated with carbon (II) oxide and sulphur (IV) oxide was passed through the apparatus shown in the diagram below. Which contaminant was removed by passing the contaminated air through the apparatus? Explain.
  1m 54s

• 4.    Oxygen reacts with elements phosphorus, sulphur and chlorine to form oxide in which the element is in its highest oxidation number. The table below gives the oxide of sulphur and its highest oxidation number. Complete the table for phosphorus and chlorine. (Atomic numbers: P=15, S=16, Cl=17)
  4m 34s

• 5.    Study the flow chart below and answer question that follow. (a) Name; (ii) Gas U (b) Give the chemical test that you could use to identify gas U.
  3m 8s

• 6.    Urea,#(NH_2)_2CO#, is prepared by the reaction between ammonia and carbon (IV) oxide. #2NH_3(g)+CO_2(g)to(NH_2)_2CO(aq)+H_2O(l)# In the process, 680kg of ammonia were reacted with excess carbon (IV) oxide. Calculate the mass of urea that was formed. (H=1.0, C=12.0, N=14.0, O=16.0 and relative molecular mass of ammonia=17)
  5m 24s

• 7.    State and explain the observation that would be made when a few drops of concentrated sulphuric (VI) acid are added to a small sample of hydrated copper (II) sulphate.
  1m 39s

• 8.    Sulphur (IV) oxide and nitrogen (IV) oxide react as shown in the equation below. #SO_2(g)+NO_2(g)toSO_3(g)+NO(g)#
  4m 51s

• 9.    When a solid sample of sulphur is heated in a test tube, it changes into a liquid which flows easily. On further heating, the liquid darkens and does not flow easily. Explain these observations.
  1m 24s

• 10.    When a sample of concentrated sulphuric (VI) acid was left in an open beaker in a room for two days, the volume was found to have increased slightly.
  1m 23s

• 11.    The apparatus shown below was set to prepare and collect hydrogen sulphide gas. (a) Name solid #C_2# (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?
  1m 15s

• 12.    In an experiment, sulphur (IV) oxide gas was bubbled into water followed by chlorine gas. The resulting clear solution gave a white precipitate when mixed with acidified barium chloride solution. Explain these observations.
  1m 44s

• 13.    Sulphur exists in two crystalline forms. (a) Name one crystalline form sulphur (b) Give any two uses of sulphur.
  0m 50s

• 14.    Oleum (#H_2S_2O_7#) is an intermediate product in the industrial manufacture of sulphuric acid (a) How is oleum converted into sulphuric (VI) acid? (b) Give one use of sulphuric (VI) acid.
  1m 5s

• 15.    Determine the oxidation state of sulphur in the following compounds: (a) #H_2S# (b) #Na_2SO_3#
  3m 23s

• 16.    In an experiment to study the properties of concentrated sulphuric (VI) acid, a mixture of the acid and wood charcoal was heated in a boiling tube. (a) Write the equation of the reaction that took place in the boiling tube. (b) Using the oxidation numbers, show that reduction and oxidation reactions took place in the boiling tube.
  5m 37s

• 17.    When hydrogen sulphide gas was bubbled into an aqueous solution of iron (III) chloride, a yellow precipitate was deposited. (a) State another observation made (b) Write an equation for the reaction that took place. (c) What type of reaction was undergone by hydrogen sulphide in this reaction?
  3m 6s

• 18.    Study the flow chart below and answer the questions that follow. (a) Name reagent Z (b) Describe the process which takes place in step 2 (c) Identify the white solid.
  2m 25s

• 19.    (a) State the observation made at the end of the experiment when a mixture of iron powder and sulphur is heated in a test tube. (b) Write an equation for the reaction between the product in (a) above and dilute hydrochloric acid (c) When a mixture of iron powder and sulphur is heated, it glows more brightly than that of iron fillings and sulphur. Explain this observation.
  1m 57s

• 20.    In an attempt to prepare sulphur (IV) oxide gas, dilute sulphuric (VI) acid was reacted with barium sulphite. The yield of sulphur (IV) oxide was found to be negligible. Explain.
  0m 57s

• 21.    A certain matchstick head contains potassium chlorate and sulphur. On striking, the two substances react to produce sulphur (IV) oxide and potassium chloride. Explain the environmental effect of using such matches in large numbers.
  1m 3s

• 22.    Describe a simple laboratory experiment that can be used to distinguish between sodium sulphide and sodium carbonate.
  2m 51s

• 23.    Dilute hydrochloric acid and solid sodium sulphite were reacted as shown in the set-up below. (a) Name the gas produced in the flask (b) Give two reasons why no gas was collected in the gas jar.
  2m 18s

• 24.    Below is a sketch of a graph showing the change in viscosity (Ease of flow) with temperature when solid sulphur is heated. Describe what happens to the sulphur molecules when sulphur is heated from #150^0C# to about# 200^0C#.
  1m 48s

• 25.    Potassium sulphite solution was prepared and divided into two portions. The first portion gave a white precipitate when reacted with barium nitrate. On addition of dilute hydrochloric acid, the white precipitate disappeared. (a) Write the formula of the compound which formed as the white precipitate (b) Write the equation for the reaction between dilute hydrochloric acid and the compound whose for
  3m 8s

• 26.    (a) The diagram below shows a set-up used by a student in an attempt to prepare and collect oxygen gas. (i) Complete the diagram by correcting the mistakes on it. (ii) Identify solid W (b) A piece of phosphorus was burnt in excess air and the product obtained was shaken with a small amount of hot water to make a solution (i) Write an equation for the burning of phosphorus in excess air.
  10m 20s

• 27.    (a) The diagram below shows some processes that take place during the industrial manufacture of sulphuric (VI) acid. (i) Write the equation for the reaction in which sulphur (IV) 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 the environment (v) State and explain the
  11m 29s

• 28.    Zinc reacts with both concentrated and dilute sulphuric (VI) acid. Write equations for two reactions.
  1m 14s

• 29.    Crude oil contains sulphur. What would be the effect to the environment of using fuel containing sulphur?
  0m 24s

• 30.    Hydrogen sulphide is a highly toxic and flammable gas. It is normally prepared in a fume chamber. (a) Name two reagents that can be used to prepare hydrogen sulphide in the laboratory. (b) One of the uses of hydrogen sulphide is to produce sulphur as shown in the following equation: #2H_2S(g) +SO_2(g) 3S(s) + 2H_2O#(l) Identify the reducing agent in this reaction and give a reason for your answer.
  1m 39s

• 31.    The set up below was used to prepare a gas and study some of its properties. Study it and answer the questions that follow: (a) State and explain the observations made in the: (i) Tube labeled A; (ii) Beaker labeled B (b) State one precaution that should be taken when carrying out this experiment.
  1m 59s

• 32.    The flowchart below shows some of the processes involved in large scale production of sulphuric (IV) acid. Use it to answer the questions that follow. (a)Describe how oxygen is obtained from air on a large scale. (b) (i) Name substance A. (ii)Write an equation for the process that takes place in the absorption chamber. (c) Vanadium (V) oxide is a commonly used catalyst in the contact process.
  3m 38s

• 33.    Acidified potassiummanganite(VII)solution is decolourised when sulphur(VI) oxide is bubbled through it. The equation for the reaction is given below. #2H_2O(l) + 5SO_2(g) +2KMnO_4(aq)rightarrow K_2SO_4(aq) +2MnSO_4(aq) +2H_2SO_4(aq)# (a) Which reactant is oxidized? Explain. (b) Other than the manufacture of sulphuric (IV) acid, state one other use of sulphur (IV) oxide.
  1m 4s

• 34.    (a) What would be observed if sulphur (IV) oxide is bubbled through acidified potassium manganite (VII)? (b) In an experiment, sulphur (IV) oxide was dissolved in water to form solution L. (i)What would be observed if a few drops of barium nitrate solution were immediately added to solution L? (ii) Write an ionic equation for the reaction that occurred between solution L and aqueous barium nitrate
  1m 32s