COMPOUNDS OF SULPHUR

Subject :Chemistry

Term : Second Term

Week :Week 9

Topic :

COMPOUNDS OF SULPHUR

 

Objective: By the end of this lesson, students will be able to:

• Define sulphur and its compounds.
• Explain the properties and uses of sulphur and its compounds.
• Identify the laboratory methods of preparing hydrogen sulphide and sulphur dioxide gases.
• Understand the safety precautions involved in handling hydrogen sulphide and sulphur dioxide gases in the laboratory.
• Demonstrate how to prepare hydrogen sulphide and sulphur dioxide gases in the laboratory.

Materials:

• Chalkboard and chalk
• Projector and screen
• Handouts for note-taking
• Kipp’s apparatus
• Hydrochloric acid
• Sodium trioxosulphate (IV)
• Copper (II) oxide
• Sulphur powder

Introduction (10 minutes)

 

Previous Lesson

SULPHUR :GENERAL PROPERTIES OF SULPHUR GROUP

WEEK NINE

DATE: _________

TOPIC: COMPOUNDS OF SULPHUR

CONTENT

• H2S, SO2 and SO3: Preparation, Properties and Uses
• Tetraoxosulphate (VI) acid: Industrial Preparation (Contact Process).

COMPOUNDS OF SULPHUR

Compounds of sulphur are chemicals that contain the element sulphur. Sulphur is a non-metal element with the atomic number 16 and is found in nature in various forms like sulphur dioxide (SO2), hydrogen sulphide (H2S), and sulphuric acid (H2SO4). Some examples of compounds of sulphur include:

1. Sulphur dioxide (SO2) – This is a gas that is released into the air when fossil fuels like coal and oil are burned. It is also used in the production of sulphuric acid. Sulphur dioxide is an important air pollutant that can cause respiratory problems in humans.
2. Hydrogen sulphide (H2S) – This is a gas that has a strong smell of rotten eggs. It is produced by decaying organic matter and is also found in some natural gas and oil reserves. Hydrogen sulphide is highly toxic and can cause nausea, headaches, and even death in high concentrations.
3. Sulphuric acid (H2SO4) – This is a highly corrosive acid that is used in many industrial processes, including the production of fertilizers, dyes, and detergents. It is also used in the manufacturing of lead-acid batteries. Sulphuric acid is a dangerous chemical that can cause severe burns and is highly reactive with many other chemicals.
4. Iron sulphide (FeS) – This is a mineral that is commonly found in rocks and soils. It is also known as pyrite or “fool’s gold” because it has a shiny appearance similar to gold. Iron sulphide is often used as a source of sulphur in the production of sulphuric acid.
5. Zinc sulphate (ZnSO4) – This is a white crystalline powder that is used as a dietary supplement for animals and as a fertilizer for plants. It is also used in the production of pigments, wood preservatives, and paper. Zinc sulphate can be toxic if ingested in large quantities.

Overall, compounds of sulphur are important chemicals that have a wide range of uses in industry and everyday life. However, many of them can be dangerous if not handled properly, and it is important to follow safety guidelines when working with these chemicals

 

Evaluation

1. Which of the following is a gas that is released into the air when fossil fuels are burned? a) Sulphuric acid b) Hydrogen sulphide c) Sulphur dioxide d) Iron sulphide
2. What is the common name for FeS? a) Zinc sulphate b) Sulphuric acid c) Hydrogen sulphide d) Iron sulphide
3. What is the chemical formula for zinc sulphate? a) ZnSO4 b) H2SO4 c) FeS d) SO2
4. What is the chemical formula for sulphuric acid? a) ZnSO4 b) H2SO4 c) FeS d) SO2
5. Which of the following is a mineral that is commonly found in rocks and soils? a) Hydrogen sulphide b) Sulphuric acid c) Sulphur dioxide d) Iron sulphide
6. What is the main use of sulphuric acid in industry? a) As a dietary supplement for animals b) In the production of fertilizers, dyes, and detergents c) As a source of sulphur in the production of sulphuric acid d) In the production of pigments, wood preservatives, and paper
7. Which of the following is highly toxic and can cause nausea, headaches, and even death in high concentrations? a) Sulphur dioxide b) Hydrogen sulphide c) Sulphuric acid d) Iron sulphide
8. What is the chemical formula for hydrogen sulphide? a) ZnSO4 b) H2SO4 c) FeS d) H2S
9. Which of the following is an important air pollutant that can cause respiratory problems in humans? a) Sulphuric acid b) Hydrogen sulphide c) Sulphur dioxide d) Iron sulphide
10. Which of the following is a gas that has a strong smell of rotten eggs? a) Sulphuric acid b) Hydrogen sulphide c) Sulphur dioxide d) Iron sulphide

HYDROGEN SULPHIDE, H2S 

Hydrogen sulphide is found in volcanic gases, sulphur springs, coal gas and natural gas. 

Hydrogen sulphide (H2S) is a gas with a foul smell of rotten eggs. It is a chemical compound made up of two hydrogen atoms and one sulphur atom. It is found naturally in volcanic gases, sulphur springs, coal gas and natural gas.

Although hydrogen sulphide can be found naturally, it can also be produced by human activities, such as the refining of petroleum or the processing of natural gas. It is also produced by the breakdown of organic matter, such as sewage, animal waste, and decaying plants and animals.

Hydrogen sulphide is highly toxic and can be dangerous when inhaled in large quantities. It is heavier than air, so it can accumulate in low-lying areas such as basements, sewers and underground storage tanks. When hydrogen sulphide is inhaled, it can irritate the respiratory system, cause headaches, dizziness, nausea, and even death in high concentrations.

Despite its toxic nature, hydrogen sulphide is also used in some industrial processes. For example, it is used in the production of sulphuric acid, in the manufacture of metal sulphides, and in the production of organic chemicals.

In summary, hydrogen sulphide is a naturally occurring gas that has a foul smell of rotten eggs. It can be found in volcanic gases, sulphur springs, coal gas and natural gas. While it has some industrial applications, it can be extremely dangerous in high concentrations and requires proper handling and safety measures to prevent accidents and exposure

LABORATORY PREPARATION 

Hydrogen sulphide is prepared in the laboratory by the action of dilute acids on metallic sulphide like Iron (II) sulphide

                2HCl(aq)    +    FeS(s) → FeCl2(aq) + H2S(g)

The apparatus used for regular supply of hydrogen sulphide in the laboratory is Kipp’s apparatus.

Hydrogen sulphide (H2S) is a gas with a foul smell of rotten eggs that can be prepared in the laboratory using various methods. One common method involves the reaction of dilute acids, such as hydrochloric acid (HCl) or sulfuric acid (H2SO4), with metallic sulphides like Iron (II) sulphide (FeS):

2HCl(aq) + FeS(s) → FeCl2(aq) + H2S(g)

In this reaction, the acid reacts with the metallic sulphide to form a salt, such as iron chloride (FeCl2), and hydrogen sulphide gas is released as a product. The gas can then be collected in a gas syringe or other apparatus for further use.

The apparatus used for regular supply of hydrogen sulphide in the laboratory is called Kipp’s apparatus. It consists of a cylindrical vessel with three compartments. The top compartment holds the solid metallic sulphide, the middle compartment holds the dilute acid, and the bottom compartment holds the gas produced. The apparatus also has a tap or valve for controlling the flow of gas.

To use the Kipp’s apparatus, the metallic sulphide is placed in the top compartment and the dilute acid is added to the middle compartment. The reaction produces hydrogen sulphide gas, which is collected in the bottom compartment. The tap or valve is used to control the flow of gas, allowing for safe and accurate handling of the gas in the laboratory.

In summary, hydrogen sulphide can be prepared in the laboratory by the reaction of dilute acids with metallic sulphides like Iron (II) sulphide. The Kipp’s apparatus is a common apparatus used for regular supply of hydrogen sulphide in the laboratory, allowing for safe and accurate handling of the gas

Evaluation

1. What is the chemical formula for hydrogen sulphide? a) HCl b) H2S c) FeS d) FeCl2
2. What is the name of the metallic sulphide used in the laboratory preparation of hydrogen sulphide? a) Hydrogen sulphide b) Iron (II) sulphide c) Zinc sulphate d) Sulphuric acid
3. What is the chemical formula for hydrochloric acid? a) HCl b) H2SO4 c) FeS d) FeCl2
4. What is the chemical formula for sulphuric acid? a) HCl b) H2SO4 c) FeS d) FeCl2
5. What is the gas produced in the laboratory preparation of hydrogen sulphide? a) Hydrogen gas b) Oxygen gas c) Sulphur dioxide gas d) Hydrogen sulphide gas
6. What is the apparatus used for regular supply of hydrogen sulphide in the laboratory? a) Gas syringe b) Bunsen burner c) Kipp’s apparatus d) Beaker
7. Which compartment of the Kipp’s apparatus holds the metallic sulphide? a) Top compartment b) Middle compartment c) Bottom compartment d) None of the above
8. Which compartment of the Kipp’s apparatus holds the dilute acid? a) Top compartment b) Middle compartment c) Bottom compartment d) None of the above
9. Which product is formed when hydrochloric acid reacts with Iron (II) sulphide? a) Hydrogen gas b) Oxygen gas c) Iron chloride d) Hydrogen sulphide gas
10. What is the purpose of the tap or valve on the Kipp’s apparatus? a) To hold the metallic sulphide b) To hold the dilute acid c) To control the flow of gas d) To prevent the formation of gas

PHYSICAL PROPERTIES 

1. Hydrogen sulphide is a colourless gas with smell like that of rotten egg. 
2. It is a very poisonous. 
3. It is about 1.18 times denser than air. 
4. It is moderately soluble in water to form very weak acidic solution. 
5. It burns with pale blue flame.

 

CHEMICAL PROPERTIES 

1. As an acid it reacts with alkali to form a normal salt and water

2NaOH(aq)     +     H2S(g) → Na2S(aq)   +    2H2O(l)

1. It reacts with excess oxygen to form sulphur (VI) oxide but forms deposit of sulphur with limited oxygen 

2H2S(g)   + 3O2(g)   →     2H2O(l) + 2SO2(g)

2H2S(g)   +  O2(g)   →     2H2(l) + 2S(s)

1. As a reducing agent, it reacts with many oxidizing agents such as         acidified KMnO4, acidified K2Cr2O7, chlorine gas, FeCl2, SO2, H2SO4 and HNO3

 

TEST FOR HYDROGEN SULPHIDE 

A piece of filter paper is moisten with lead (II) trioxonitrate (V) solution and dropped it into a gas jar of the unknown gas. If the paper turns black, then the gas is H2S.

 

EVALUATION 

1. Name the reagents used in laboratory preparation of hydrogen sulphide. 
2. List TWO physical and chemical properties each of hydrogen sulphide.

 

SULPHUR (IV) OXIDE, SO2

Sulphur (IV) oxide, also known as sulphur dioxide (SO2), is a gas that is commonly used in industry and can be prepared in the laboratory using various methods. One common method involves the reaction of sodium or potassium trioxosulphate (IV) with tetraoxosulphate (IV) acid or hydrochloric acid:

Na2SO3(aq) + 2HCl(aq) → 2NaCl(aq) + H2O(l) + SO2(g)

In this reaction, the acid reacts with the sodium or potassium trioxosulphate (IV) to produce sodium or potassium chloride, water and sulphur dioxide gas. The gas can be collected in a gas syringe or other apparatus for further use.

Another method of preparing sulphur dioxide gas in the laboratory is by heating a mixture of copper (II) oxide and sulphur powder:

CuO(s) + S(s) → CuS(s) + SO2(g)

In this reaction, the copper (II) oxide reacts with the sulphur powder to produce copper (II) sulphide and sulphur dioxide gas. The gas can be collected in a gas syringe or other apparatus for further use.

Sulphur dioxide gas has many industrial applications, such as in the production of sulphuric acid, bleach and paper. It is also used as a food preservative and as a refrigerant. Despite its many uses, sulphur dioxide gas can be hazardous when inhaled in large quantities and should be handled with care in the laboratory.

In summary, sulphur dioxide gas can be prepared in the laboratory by reacting sodium or potassium trioxosulphate (IV) with tetraoxosulphate (IV) acid or hydrochloric acid, or by heating a mixture of copper (II) oxide and sulphur powder. Sulphur dioxide gas has many industrial applications but should be handled with care in the laboratory.

LABORATORY PREPARATION 

Sulphur (IV) oxide is prepared in the laboratory by heating sodium or potassium trioxosulphate (IV) with tetraoxosulphate (IV) acid or hydrochloric acid. 

         Na2SO3(aq)    +   2HCl(aq) →   2NaCl(aq) + H2O(l) + SO2(g)

 

PHYSICAL PROPERTIES 

1. Sulphur (IV) oxide is a colourless poisonous gas with smell like that of burning matches.
2. It is very soluble in water. 
3. It is about 2.5 times denser than air.

 

CHEMICAL PROPERTIES 

1. As an acid, it reacts with alkali to form normal salt of trioxosulphate and water only 

2NaOH(aq)    +     SO2(g) → Na2SO3(aq)  +  H2O(l)

1. As reducing agent, sulphur (IV) oxide reacts with many oxidizing agents such as acidified KMnO4; acidified K2Cr2O7; FeCl3, HNO3, chlorine gas. It decolorizes acidified purple KMnO4 and turns acidified orange K2Cr2O7 to green. 
2. It reacts as bleaching agent decolourising dye by its bleaching action. The bleaching action is similar to that of chlorine in that there must be water. But, while chlorine bleaches by oxidation sulphur IV oxide bleaches by reduction.
3. Sulphur (IV) oxide reacts as oxidizing agent in the presence of strong reducing agent such as hydrogen sulphide. 

2H2S(g)   +    SO2(g) → 2H2O(l)    +    3S(s)

C(s) +   SO2(g) →     CO2(g)    +    S(s)

 

TEST FOR SO2

1. If an unknown gas bleaches a coloured flower, SO2 can be suspected 
2. The unknown gas bubbled through solution of either acidified potassium heptaoxodichromate (VI) or potassium tetraoxomanganate (VII). If orange colour of the acidified K2Cr2O7 turn green or the purple colour of the  acidified KMnO4 turns colourless, then the unknown gas is SO2

 

USES 

1. It is used in manufacture of tetraoxosulphate (VI) acid. 
2. It is used as a germicides and a fumigant especially for destroying termites. 
3. It is used as bleaching agent for straw, silt and wood.
4. It is used as preservative in some liquid e.g orange juice. 
5. Liquid sulphur (IV) oxide is used as refrigerant.

 

EVALUATION

1. Give one method of preparing sulphur (IV) oxide in the laboratory.
2. State THREE physical and chemical properties of sulphur (IV) oxide.

1. What is another name for sulphur (IV) oxide? a) Sulphur trioxide b) Sulphur dioxide c) Sulphur monoxide d) Sulphur hexafluoride
2. What is the chemical formula for sulphur (IV) oxide? a) SO2 b) SO3 c) H2SO4 d) H2SO3
3. What is the common laboratory method for preparing sulphur (IV) oxide? a) Heating sodium or potassium trioxosulphate (IV) with water b) Reacting copper (II) oxide with sulphuric acid c) Heating magnesium oxide with hydrochloric acid d) Heating sodium or potassium trioxosulphate (IV) with tetraoxosulphate (IV) acid or hydrochloric acid
4. What is the product of the reaction between sodium or potassium trioxosulphate (IV) and hydrochloric acid? a) Sodium chloride or potassium chloride b) Sulphur dioxide c) Water d) All of the above
5. What is the product of the reaction between copper (II) oxide and sulphur powder? a) Copper (II) sulphate b) Sulphur trioxide c) Copper (II) sulphide and sulphur dioxide d) Water
6. What is the main industrial application of sulphur dioxide? a) Food preservative b) Bleach production c) Sulphuric acid production d) All of the above
7. What is the apparatus commonly used to collect gases in the laboratory? a) Beaker b) Gas syringe c) Test tube d) Petri dish
8. Which acid can be used to react with sodium or potassium trioxosulphate (IV) to produce sulphur dioxide gas? a) Hydrochloric acid b) Sulfuric acid c) Nitric acid d) Acetic acid
9. What is the chemical formula for sodium trioxosulphate (IV)? a) Na2SO3 b) Na2SO4 c) NaHSO4 d) NaHCO3
10. What safety precautions should be taken when handling sulphur dioxide gas in the laboratory? a) Use in a well-ventilated area b) Wear appropriate protective equipment c) Avoid inhaling the gas d) All of the above

SULPHUR (VI) OXIDE, SO3

Sulphur (VI) oxide is prepared by reacting sulphur (IV) oxide and oxygen under special conditions which are:

1. Presence of platinized asbestos or vanadium (V) oxide as catalyst 
2. Pressure of 1atm 
3. Temperature range of 400oC – 450oC.                                   

2SO2(g)   +   O2(g) 2SO3(g)

 

PHYSICAL PROPERTIES OF SO3

1. It exists as white needle-like crystals at room temperature.
2. It has a low boiling point and vapourizes on gentle heating.
3. It dissolves readily in water to give tetraoxosulphate (VI) acid.

 

TRIOXOSULPHATE IV ACID, H2SO3

Trioxosulphate (IV) acid is a dibasic acid with a molecular formula H2SO3

 

LABORATORY PREPARATION OF H2SO3

It is prepared by the action of dilute hydrochloric acid on heated sodium trioxosulphate (IV) to produce sulphur (IV) oxide, which is then dissolved in water.

Na2SO3(s)  +   2HCl(aq)     →   2NaCl(aq) + H2O(l) + S02(g)

H2O(l)  +  SO2(g)                 H2SO3(aq)

Sulphur (IV) Oxide is the acid anhydride of trioxosulphate (IV) acid.

 

PHYSICAL PROPERTIES OF H2SO3

1. It turns blue litmus paper red.
2. It is colourless liquid. 
3. It is mixes readily with water.

4 It has an irritating and choking smell.

 

CHEMICAL PROPERTIES OF H2SO3

1. It reacts with alkalis to form salt and water.

2NaOH(aq) + H2SO3(aq)    →    Na2SO3(aq)  + 2H2O(l)

1. It is oxidized in air to tetraoxosulphate (VI) acid

2H2SO3(aq)  +  O2(g)   →  2H2SO4(aq)

1. It reduces oxidizing agent such as potassium tetraoxomanganate (VII) and potassium heptaoxodichromate (VI).
2. It bleaches dyes in the presence of water.

 

TEST FOR SO32-

Barium chloride solution is added to the solution of the unknown substance. A white 

precipitate soluble in dilute hydrochloric acid confirms the presence of a trioxosulphate (IV) 

ion.

 

USES OF H2SO3

1. It is used for bleaching straw and other fabrics.
2. It is used as a germicide.

 

EVALUATION

1. Write an equation of reaction for the laboratory preparation of trioxosulphate IV
2. State two physical and two chemical properties of trioxosulphate IV

 

TETRAOXOSULPHATE VI ACID, H2SO4

Tetraoxosulphate VI acid is one of the most important chemical compounds known. It is used in almost every manufacturing process; hence it is mostly prepared industrially.

 

INDUSTRIAL PREPARATION OF H2SO4

Industrially, tetraoxosulphate VI acid is manufactured by Contact process. The following steps are involved in Contact process. 

1. Burning sulphur in dry air to obtain sulphur (IV) oxide, SO2

S(s) +  O2(g) → SO2(g) 

1. The sulphur (IV) oxide produced is mixed with excess air and passed through an electric chamber to remove impurities and dust which may poison the catalyst. The gaseous mixture is then passed through concentrated H2SO4 to dry it before passing it into the reaction chamber.
2. The dried gaseous mixture is delivered to the contact tower (reaction chamber) where the sulphur (IV) oxide and oxygen combine in the presence of pellets of catalyst, vanadium (V) oxide, V2O5 to yield sulphur (VI) oxide. The reaction takes place at atmospheric pressure and temperature of 450-500oC. 

           2SO2(g)  +  O2(g)                     2SO3(g) + heat 

1. The sulphur (VI) oxide is cooled and then dissolved in concentrated H2SO4 to produce a thick liquid called Oleum. 

         H2SO4(aq) +  SO3(g)  → H2S2O7(aq) 

1. The Oleum is then diluted with water appropriately to produce 98% tetraoxosulphate (VI) acid. 

H2O(l)  +  H2S2O7(aq)  →  2H2SO4(aq)

 

NOTE: Sulphur (VI) oxide is not dissolved directly in water to produce the acid because of the large amount of heat that is evolved in the process. The heat is capable of boiling the acid formed to produce mist of droplets which can spread throughout the factory and cause acid burns.

 

PHYSICAL PROPERTIES 

1. It is a colourless, vicious liquid with density of 1.84gcm-3
2. It is corrosive and cause burns when in contact with the skin. 
3. It is highly soluble in water evolving large amount of heat.

 

CHEMICAL PROEPERTIES 

1. As an acid, it reacts with metal which are above hydrogen in the electrochemical series to liberate hydrogen gas 

Zn(s)  +  H2SO4(aq)    → ZnSO4(aq)  +  H2(g)

1. It reacts with bases to form salts and water 

MgO(s)  + H2SO4(aq) →  MgSO4(aq)  +  H2O(l)

1. It reacts with alkali to form normal and acidic salt 

H2SO4(aq)    +    NaOH(aq)  → NaHSO4(aq)  + H2O(l)

H2SO4(aq)    +    NaOH(aq) → Na2 SO4(aq) + 2H2O(l)

1. As an acid, it reacts with trioxocarbonate (IV) to liberate carbon (IV) oxide 

H2SO4(aq)   + CuCO3(aq) →  CuSO4(aq)  +  H2O(l) + CO2(g)

1. As oxidizing agent, concentrated H2SO4 oxidize metals, non –metals and hydrogen sulphide in the following ways. 

Zn(s) +  2H2SO4(aq) →  ZnSO4(aq)  +  2H2O(l) +  SO2(g)

C(s) + 2H2SO4(aq) →  2H2O(l)  +  CO2(g)  + 2SO2(g)

H2SO4(aq) +  H2S(g) →  S(s)  +  H2O(l)  +  SO2(g)

6. Concentrated tetraoxosulphate (VI) acid is a dehydrating agent, removing water from compounds like sugar, ethanol, methanoic acid and ethanedioic acid 

C12H22O11(s)     →      12C(s)      +    11H2O(l)

sugar                   charcoal

7. Concentrated tetraoxosulphate (VI) displaces volatile acids from their salts 

KCl(s) +  H2SO4(aq) → KHSO4(aq) + HCl(g)

 

TEST FOR SO42-

Barium chloride solution is added to the solution of the unknown substance. A white precipitate insoluble in excess dilute hydrochloric acid confirms the presence of a tetraoxosulphate (VI) ion.

 

USES OF H2SO4

1.  It is used in production of fertilizers e.g ammonium tetraoxosulphate (VI). 
2. It is used in purification of crude oil. 
3. It is used as an electrolyte in lead acid accumulator. 
4. It is used as drying agent for many gases except NH3 and H2S gas. 
5. It is used to clean metals before electroplating.

 

USES OF TETRAOXOSULPHATE (VI) SALTS 

1. Ammonium tetraoxosulphate (VI) used as fertilizers 
2. Sodium tetraoxosulphate (VI) is used in paper manufacture and as a purgative 
3. Calcium tetraoxosulphate (VI) is mined as gypsum and when heated forms plaster of Paris used to set broken bones. 
4. Aluminum tetraoxosulphate (VI) is used to coagulate precipitate in purification of water 
5. Iron II tetraoxosulphate (VI) is used to treat anaemia.

 

GENERAL EVALUATION/REVISION 

1. Using equations only, outline the steps involve in the Contact process. 
2. State THREE physical and chemical properties each of tetraoxosulphate (VI) acid 
3. Give three uses of tetraoxosulphate (VI) salts.
4.  A current is passed through three electrolytic cells connected in series containing solutions of silver trioxonitrate (V), copper (II) tetraoxosulphate (VI) and brine respectively. If 12.7g of copper is deposited in the second electrolytic cell, calculate

1. the mass of silver deposited in the first cell, 
2. the volume of chlorine liberated in the third cell at 17oC and 800mmHg pressure. [Ag = 108, Cu = 63.5, 1F = 96500C, Molar gas volume at s.t.p = 22.4 dm3]

1. 1.33dm3 of water at 70oC is saturated by 2.25moles of lead (II) trioxonitrate (V), and 1.33dm3 of water at 18oC saturated by 0.53mole of the same salt. If 4.50dm3 of the saturated solution are cooled from 70oC to 18oC, calculate the amount of solute that will be deposited in 

1. moles
2. grams  [ Pb = 207, N= =14 O = 16]

 

READING ASSIGNMENT

New School Chemistry for Senior Secondary School by O. Y. Ababio (6th edition), pages 384-396

 

WEEKEND ASSIGNMENT

SECTION A:  Write the correct option ONLY.

1. The acid anhydride of tetraoxosulphate (VI) acid is a. SO2 b. SO3 c. SO4 d. SO
2. Which of the following compounds gives a white precipitate with acidified barium chloride solution? a. K2SO4 b. NaNO3 c. KCl d. CaCO3
3. Why do we acidify the solution used for testing for the presence of S042-a. To prevent the precipitation of any other ion that may be present in the solution. b. To acidify the test solution. c. To increase the rate of the reaction d. The acid acts as catalyst.
4. Which of the following is used as catalyst in the Contact process? a. V2O5 b. Platinum c. Fe3O2 d. Nickel
5. What is the colour of tetraoxosulphate VI acid? a. Colourless b. White c. Blue d. Pale white

 

SECTION B

1. Explain why sulphur (VI) oxide is not dissolve directly in water during the Contact process for preparing tetraoxosulphate (VI) acid.
2. Using balanced equations ONLY, describe the stages involved in the manufacture of tetraoxosulphate (VI) acid using the Contact process.

Lesson Plan Presentation

Subject: Chemistry Topic: Sulphur and Its Compounds

Grade: SS 2

Time: 60 minutes

 

 

Introduction (10 minutes)

• Greet the students and introduce the topic of the day.
• Ask students what they know about sulphur and its compounds.
• Define sulphur and its compounds, and explain their importance in our daily lives.

Body (40 minutes)

• Present a PowerPoint presentation on sulphur and its compounds, including their properties, uses, and laboratory preparation methods.
• Discuss the safety precautions involved in handling hydrogen sulphide and sulphur dioxide gases in the laboratory.
• Demonstrate how to prepare hydrogen sulphide and sulphur dioxide gases using Kipp’s apparatus, hydrochloric acid, sodium trioxosulphate (IV), copper (II) oxide, and sulphur powder.
• Allow time for students to ask questions and take notes.

Conclusion (10 minutes)

• Summarize the main points covered in the lesson.
• Review the key concepts and encourage students to ask questions.
• Assign homework or independent research on a related topic.

Assessment:

• Monitor students’ participation during the lesson.
• Assess students’ understanding of the topic through class discussions and questions.
• Evaluate students’ ability to prepare hydrogen sulphide and sulphur dioxide gases in the laboratory.

Weekly Assessment /Test

1. What is sulphur? a) A metal b) A non-metal c) A metalloid d) A liquid
2. Which of the following is a compound of sulphur? a) Sulphuric acid b) Hydrogen sulphide c) Sulphur dioxide d) All of the above
3. What is the common laboratory method for preparing hydrogen sulphide? a) Heating sulphur powder with oxygen gas b) Reacting hydrochloric acid with magnesium ribbon c) Heating sodium or potassium trioxosulphate (IV) with tetraoxosulphate (IV) acid or hydrochloric acid d) None of the above
4. What is the chemical formula for hydrogen sulphide? a) HCl b) H2SO4 c) H2S d) H2O
5. What is the apparatus used for regular supply of hydrogen sulphide in the laboratory? a) Gas syringe b) Bunsen burner c) Kipp’s apparatus d) Beaker
6. What is the common laboratory method for preparing sulphur dioxide? a) Heating sodium or potassium trioxosulphate (IV) with water b) Reacting copper (II) oxide with sulphuric acid c) Heating magnesium oxide with hydrochloric acid d) Heating sodium or potassium trioxosulphate (IV) with tetraoxosulphate (IV) acid or hydrochloric acid
7. What is the chemical formula for sulphur dioxide? a) SO2 b) SO3 c) H2SO4 d) H2SO3
8. Which of the following is a common industrial application of sulphur dioxide? a) Food preservative b) Bleach production c) Sulphuric acid production d) All of the above
9. What safety precautions should be taken when handling hydrogen sulphide gas in the laboratory? a) Use in a well-ventilated area b) Wear appropriate protective equipment c) Avoid inhaling the gas d) All of the above
10. What is the product of the reaction between copper (II) oxide and sulphur powder? a) Copper (II) sulphate b) Sulphur trioxide c) Copper (II) sulphide and sulphur dioxide d) Water
11. _______ is a non-metal element that can exist in different forms such as crystals, powder, and liquid.
12. _______ is a compound of sulphur that is commonly used in battery production.
13. Hydrogen sulphide has a characteristic smell of _______.
14. In the laboratory, hydrogen sulphide is prepared by the action of dilute acids on metallic sulphides like _______ sulphide.
15. The apparatus used for regular supply of hydrogen sulphide in the laboratory is called _______ apparatus.
16. Sulphur dioxide is commonly used in the production of _______ acid.
17. The common laboratory method for preparing sulphur dioxide is by heating sodium or potassium trioxosulphate (IV) with _______ acid.
18. Sulphur dioxide gas is harmful to human health when inhaled in large quantities and can cause _______.
19. The reaction between copper (II) oxide and sulphur powder produces copper (II) sulphide and _______ gas.
20. _______ precautions must be taken when handling hydrogen sulphide and sulphur dioxide gases in the laboratory.
21. What is sulphur and what are its properties?
22. Name three common compounds of sulphur and their uses.
23. What is the characteristic smell of hydrogen sulphide?
24. How is hydrogen sulphide prepared in the laboratory?
25. What is the purpose of Kipp’s apparatus in the laboratory preparation of hydrogen sulphide?
26. What is sulphur dioxide and what are its industrial applications?
27. What is the common laboratory method for preparing sulphur dioxide?
28. What are the potential health hazards of sulphur dioxide gas?
29. How is sulphur dioxide gas prepared in the laboratory using copper (II) oxide and sulphur powder?
30. What safety precautions should be taken when handling hydrogen sulphide and sulphur dioxide gases in the laboratory?