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The formula of copper(II) tetraoxosulphate(VI) is:- a)CuSO4
- b)CuSO3
- c)CuSO4.5H2O
- d)CuSO4.H2O
Correct answer is option 'A'. Can you explain this answer?
The formula of copper(II) tetraoxosulphate(VI) is:
a)
CuSO4
b)
CuSO3
c)
CuSO4.5H2O
d)
CuSO4.H2O
|
Omowunmi Nnamdi answered |
Explanation:
Copper(II) tetraoxosulphate(VI) is a compound that consists of copper ions (Cu2+) and tetraoxosulphate(VI) ions (SO42-). The formula of this compound is CuSO4.
Breaking Down the Name:
To understand the formula of copper(II) tetraoxosulphate(VI), let's break down the name of the compound:
1. Copper(II): This indicates that the copper ion in the compound has a +2 charge. Copper can exist in different oxidation states, and in this case, it has a +2 charge.
2. Tetraoxosulphate(VI): This refers to the tetraoxosulphate(VI) ion, which is also known as sulfate ion (SO42-). The "tetra" prefix indicates that there are four oxygen atoms in the ion, and the "oxo" prefix indicates the presence of oxygen.
Combining the Ions:
The formula of a compound is determined by the charges of the ions involved. In copper(II) tetraoxosulphate(VI), the copper ion has a +2 charge, and the tetraoxosulphate(VI) ion has a -2 charge.
To balance the charges, we need two copper ions (2 x +2 = +4) and one tetraoxosulphate(VI) ion (-2). Therefore, the formula becomes Cu2(SO4).
However, we need to consider the overall charge neutrality of the compound. Since there are two copper ions with a +2 charge each, the total positive charge is +4. To balance this, we need two tetraoxosulphate(VI) ions (-2 x 2 = -4).
The final formula becomes Cu2(SO4)2, but we simplify it by removing the subscript "2" from the copper ion, giving us CuSO4.
Conclusion:
In summary, the formula of copper(II) tetraoxosulphate(VI) is CuSO4. This compound consists of copper ions (Cu2+) and tetraoxosulphate(VI) ions (SO42-). The charges of the ions are balanced to give a neutral compound.
Copper(II) tetraoxosulphate(VI) is a compound that consists of copper ions (Cu2+) and tetraoxosulphate(VI) ions (SO42-). The formula of this compound is CuSO4.
Breaking Down the Name:
To understand the formula of copper(II) tetraoxosulphate(VI), let's break down the name of the compound:
1. Copper(II): This indicates that the copper ion in the compound has a +2 charge. Copper can exist in different oxidation states, and in this case, it has a +2 charge.
2. Tetraoxosulphate(VI): This refers to the tetraoxosulphate(VI) ion, which is also known as sulfate ion (SO42-). The "tetra" prefix indicates that there are four oxygen atoms in the ion, and the "oxo" prefix indicates the presence of oxygen.
Combining the Ions:
The formula of a compound is determined by the charges of the ions involved. In copper(II) tetraoxosulphate(VI), the copper ion has a +2 charge, and the tetraoxosulphate(VI) ion has a -2 charge.
To balance the charges, we need two copper ions (2 x +2 = +4) and one tetraoxosulphate(VI) ion (-2). Therefore, the formula becomes Cu2(SO4).
However, we need to consider the overall charge neutrality of the compound. Since there are two copper ions with a +2 charge each, the total positive charge is +4. To balance this, we need two tetraoxosulphate(VI) ions (-2 x 2 = -4).
The final formula becomes Cu2(SO4)2, but we simplify it by removing the subscript "2" from the copper ion, giving us CuSO4.
Conclusion:
In summary, the formula of copper(II) tetraoxosulphate(VI) is CuSO4. This compound consists of copper ions (Cu2+) and tetraoxosulphate(VI) ions (SO42-). The charges of the ions are balanced to give a neutral compound.
The process of heating iron ore in the presence of air to remove impurities is called:- a)Calcination
- b)Roasting
- c)Reduction
- d)Smelting
Correct answer is option 'B'. Can you explain this answer?
The process of heating iron ore in the presence of air to remove impurities is called:
a)
Calcination
b)
Roasting
c)
Reduction
d)
Smelting
|
Halima Bakare answered |
Roasting is the process of heating iron ore in the presence of air to remove impurities. It is an important step in the production of iron from iron ore.
Roasting is a thermal treatment that involves the application of heat to ores to bring about physical and chemical changes. In the case of iron ore, roasting involves heating the ore in the presence of air to remove impurities such as sulfur, arsenic, and carbonaceous materials. This process is carried out prior to the smelting of the ore.
The roasting process involves several stages:
1. Crushing and Grinding:
The iron ore is first crushed and ground to a fine powder. This increases the surface area of the ore, allowing for more efficient contact between the ore and the air during roasting.
2. Drying:
The crushed ore is then dried to remove any moisture present. This is important as moisture can interfere with the roasting process.
3. Heating:
The dried ore is then heated in a furnace or kiln. Air is blown into the furnace to provide oxygen for the roasting process. The temperature and duration of heating depend on the specific impurities present in the ore and the desired level of impurity removal.
4. Oxidation:
During roasting, the iron ore undergoes oxidation, meaning it combines with oxygen from the air. This causes the impurities to react and form volatile compounds or oxides. These volatile compounds can then be easily removed from the ore.
5. Removal of Impurities:
The volatile compounds or oxides formed during roasting are carried away by the air and removed from the furnace. This leaves behind the purified iron ore, which is ready for further processing.
Roasting is an essential step in the production of iron as it removes impurities that can negatively affect the quality of the final product. By removing sulfur, arsenic, and carbonaceous materials, roasting improves the purity and properties of the iron ore, making it suitable for smelting and subsequent use in various industries.
Roasting is a thermal treatment that involves the application of heat to ores to bring about physical and chemical changes. In the case of iron ore, roasting involves heating the ore in the presence of air to remove impurities such as sulfur, arsenic, and carbonaceous materials. This process is carried out prior to the smelting of the ore.
The roasting process involves several stages:
1. Crushing and Grinding:
The iron ore is first crushed and ground to a fine powder. This increases the surface area of the ore, allowing for more efficient contact between the ore and the air during roasting.
2. Drying:
The crushed ore is then dried to remove any moisture present. This is important as moisture can interfere with the roasting process.
3. Heating:
The dried ore is then heated in a furnace or kiln. Air is blown into the furnace to provide oxygen for the roasting process. The temperature and duration of heating depend on the specific impurities present in the ore and the desired level of impurity removal.
4. Oxidation:
During roasting, the iron ore undergoes oxidation, meaning it combines with oxygen from the air. This causes the impurities to react and form volatile compounds or oxides. These volatile compounds can then be easily removed from the ore.
5. Removal of Impurities:
The volatile compounds or oxides formed during roasting are carried away by the air and removed from the furnace. This leaves behind the purified iron ore, which is ready for further processing.
Roasting is an essential step in the production of iron as it removes impurities that can negatively affect the quality of the final product. By removing sulfur, arsenic, and carbonaceous materials, roasting improves the purity and properties of the iron ore, making it suitable for smelting and subsequent use in various industries.
The main impurity in iron ore is usually:- a)Silicon dioxide
- b)Aluminum oxide
- c)Calcium carbonate
- d)Copper sulphide
Correct answer is option 'A'. Can you explain this answer?
The main impurity in iron ore is usually:
a)
Silicon dioxide
b)
Aluminum oxide
c)
Calcium carbonate
d)
Copper sulphide
|
Deepak Iyer answered |
Silicon dioxide (SiO2), also known as silica, is the main impurity found in iron ore. It is commonly associated with iron ore deposits and needs to be removed during the extraction process.
Which form of iron is used in the construction of bridges and buildings due to its high strength?- a)Wrought iron
- b)Cast iron
- c)Steel
- d)Pig iron
Correct answer is option 'C'. Can you explain this answer?
Which form of iron is used in the construction of bridges and buildings due to its high strength?
a)
Wrought iron
b)
Cast iron
c)
Steel
d)
Pig iron
|
|
Deepak Iyer answered |
Steel is extensively used in the construction industry due to its high strength and durability. It is an alloy of iron with carbon and other elements such as manganese, chromium, and nickel. The addition of these elements imparts superior mechanical properties to steel, making it suitable for structural applications.
Which of the following statements about iron is correct?- a)Iron is a non-metal.
- b)Iron is a gas at room temperature.
- c)Iron is a good conductor of electricity.
- d)Iron is brittle and cannot be shaped.
Correct answer is option 'C'. Can you explain this answer?
Which of the following statements about iron is correct?
a)
Iron is a non-metal.
b)
Iron is a gas at room temperature.
c)
Iron is a good conductor of electricity.
d)
Iron is brittle and cannot be shaped.
|
|
Deepak Iyer answered |
Iron is a metallic element and is known for its high electrical conductivity. It is widely used in electrical wiring, transformers, and various electrical components due to its ability to efficiently conduct electric current.
What is the color of copper(II) tetraoxosulphate(VI) crystals?- a)Blue
- b)Green
- c)Red
- d)Yellow
Correct answer is option 'A'. Can you explain this answer?
What is the color of copper(II) tetraoxosulphate(VI) crystals?
a)
Blue
b)
Green
c)
Red
d)
Yellow
|
|
Deepak Iyer answered |
Copper(II) tetraoxosulphate(VI) crystals are blue in color. This blue color is often observed when copper sulphate is dissolved in water or in the solid crystalline form.
Which form of iron is known for its resistance to corrosion?- a)Wrought iron
- b)Cast iron
- c)Steel
- d)Pig iron
Correct answer is option 'A'. Can you explain this answer?
Which form of iron is known for its resistance to corrosion?
a)
Wrought iron
b)
Cast iron
c)
Steel
d)
Pig iron
|
|
Hauwa Lawal answered |
Wrought Iron
Wrought iron is known for its resistance to corrosion due to its unique composition and production process. Here's why:
- Composition: Wrought iron contains less than 0.1% carbon and is primarily made up of iron with small amounts of slag. This low carbon content makes it highly resistant to rust and corrosion compared to other forms of iron.
- Production process: Wrought iron is produced by refining pig iron in a process called puddling, which removes impurities and creates a material with a fibrous structure. This fibrous structure gives wrought iron its distinctive look and also contributes to its corrosion resistance.
- Surface treatment: Wrought iron is often coated with protective finishes, such as paint or powder coating, to further enhance its resistance to corrosion. These coatings create a barrier between the iron and the elements, preventing rust and degradation.
Overall, wrought iron's low carbon content, fibrous structure, and protective finishes make it highly resistant to corrosion, making it a popular choice for outdoor furniture, fences, and decorative elements.
The color change observed when potassium thiocyanate (KSCN) is added to a solution containing Fe3+ ions is:- a)Colorless to reddish-brown
- b)Reddish-brown to colorless
- c)Blue to yellow
- d)Yellow to blue
Correct answer is option 'A'. Can you explain this answer?
The color change observed when potassium thiocyanate (KSCN) is added to a solution containing Fe3+ ions is:
a)
Colorless to reddish-brown
b)
Reddish-brown to colorless
c)
Blue to yellow
d)
Yellow to blue
|
|
Olalekan Bakare answered |
Color Change in the Reaction between Potassium Thiocyanate (KSCN) and Fe3+ Ions
Explanation:
When potassium thiocyanate (KSCN) is added to a solution containing Fe3+ ions, a color change occurs. The initial color of the solution is colorless, and after the addition of KSCN, it turns reddish-brown.
Overview of the Reaction:
The reaction between potassium thiocyanate and Fe3+ ions involves the formation of a complex ion called iron(III) thiocyanate. This complex ion has a reddish-brown color, which accounts for the observed color change.
Key Points:
- Initial solution color: Colorless
- Final solution color: Reddish-brown
- Color change direction: Colorless to reddish-brown
Explanation of the Reaction:
1. Potassium thiocyanate (KSCN) dissociates in water to form potassium ions (K+) and thiocyanate ions (SCN-).
- KSCN(aq) ⟶ K+(aq) + SCN-(aq)
2. Fe3+ ions from another solution are present in the solution. These ions are typically in the form of a salt, such as iron(III) chloride (FeCl3), which dissociates in water to release Fe3+ ions.
- FeCl3(aq) ⟶ Fe3+(aq) + 3Cl-(aq)
3. The thiocyanate ions (SCN-) react with the Fe3+ ions to form the iron(III) thiocyanate complex ion.
- Fe3+(aq) + 3SCN-(aq) ⟶ [Fe(SCN)3](aq)
4. The iron(III) thiocyanate complex ion is responsible for the reddish-brown color observed in the final solution.
Conclusion:
In the reaction between potassium thiocyanate (KSCN) and Fe3+ ions, the color change observed is from colorless to reddish-brown. The formation of the iron(III) thiocyanate complex ion is responsible for this color change.
Explanation:
When potassium thiocyanate (KSCN) is added to a solution containing Fe3+ ions, a color change occurs. The initial color of the solution is colorless, and after the addition of KSCN, it turns reddish-brown.
Overview of the Reaction:
The reaction between potassium thiocyanate and Fe3+ ions involves the formation of a complex ion called iron(III) thiocyanate. This complex ion has a reddish-brown color, which accounts for the observed color change.
Key Points:
- Initial solution color: Colorless
- Final solution color: Reddish-brown
- Color change direction: Colorless to reddish-brown
Explanation of the Reaction:
1. Potassium thiocyanate (KSCN) dissociates in water to form potassium ions (K+) and thiocyanate ions (SCN-).
- KSCN(aq) ⟶ K+(aq) + SCN-(aq)
2. Fe3+ ions from another solution are present in the solution. These ions are typically in the form of a salt, such as iron(III) chloride (FeCl3), which dissociates in water to release Fe3+ ions.
- FeCl3(aq) ⟶ Fe3+(aq) + 3Cl-(aq)
3. The thiocyanate ions (SCN-) react with the Fe3+ ions to form the iron(III) thiocyanate complex ion.
- Fe3+(aq) + 3SCN-(aq) ⟶ [Fe(SCN)3](aq)
4. The iron(III) thiocyanate complex ion is responsible for the reddish-brown color observed in the final solution.
Conclusion:
In the reaction between potassium thiocyanate (KSCN) and Fe3+ ions, the color change observed is from colorless to reddish-brown. The formation of the iron(III) thiocyanate complex ion is responsible for this color change.
The complex ion formed when Fe2+ ions react with potassium thiocyanate (KSCN) is:- a)Fe(SCN)2+
- b)Fe(SCN)2
- c)Fe(SCN)3
- d)Fe(SCN)4-
Correct answer is option 'A'. Can you explain this answer?
The complex ion formed when Fe2+ ions react with potassium thiocyanate (KSCN) is:
a)
Fe(SCN)2+
b)
Fe(SCN)2
c)
Fe(SCN)3
d)
Fe(SCN)4-
|
|
Deepak Iyer answered |
When Fe2+ ions react with potassium thiocyanate (KSCN), the complex ion formed is iron(II) thiocyanate, which is represented as Fe(SCN)2+. The Fe2+ ion combines with the SCN- ion to form this complex.
What is the primary advantage of using steel instead of iron in construction?- a)Steel is cheaper than iron.
- b)Steel is more abundant than iron.
- c)Steel is lighter and stronger than iron.
- d)Steel does not rust like iron.
Correct answer is option 'C'. Can you explain this answer?
What is the primary advantage of using steel instead of iron in construction?
a)
Steel is cheaper than iron.
b)
Steel is more abundant than iron.
c)
Steel is lighter and stronger than iron.
d)
Steel does not rust like iron.
|
|
Deepak Iyer answered |
One of the main advantages of steel over iron is its superior strength and lighter weight. Steel has a higher tensile strength and yield strength compared to iron, allowing for the construction of structures that can bear larger loads with smaller cross-sections. Additionally, steel structures tend to be lighter, making them more cost-effective and easier to transport.
Which of the following is a disadvantage of the blast furnace method for extracting iron?- a)High energy consumption
- b)Low purity of iron obtained
- c)Generation of toxic gases
- d)All of the above
Correct answer is option 'D'. Can you explain this answer?
Which of the following is a disadvantage of the blast furnace method for extracting iron?
a)
High energy consumption
b)
Low purity of iron obtained
c)
Generation of toxic gases
d)
All of the above
|
|
Deepak Iyer answered |
The blast furnace method for extracting iron has the disadvantages of high energy consumption, low purity of iron obtained, and the generation of toxic gases as by-products.
Which of the following is an example of an oxide ore of iron?- a)Hematite
- b)Magnetite
- c)Pyrite
- d)Siderite
Correct answer is option 'A'. Can you explain this answer?
Which of the following is an example of an oxide ore of iron?
a)
Hematite
b)
Magnetite
c)
Pyrite
d)
Siderite
|
Khadijah Musa answered |
Understanding Oxide Ores of Iron
Iron ores are primarily classified based on their chemical composition. Among them, oxide ores are characterized by the presence of iron combined with oxygen.
Examples of Oxide Ores
1. Hematite (Fe2O3)
- Hematite is a major source of iron and is recognized as one of the most important iron ores.
- It consists mainly of ferric oxide and appears in colors ranging from reddish-brown to black.
- Hematite is commonly found in sedimentary rocks and is mined extensively due to its high iron content.
2. Magnetite (Fe3O4)
- While also an oxide ore, magnetite is less commonly highlighted as the primary example in some contexts.
- It contains both ferrous and ferric oxide, and is magnetic, which differentiates it from hematite.
3. Pyrite (FeS2)
- Pyrite, also known as "fool's gold," is not an oxide ore; it is a sulfide mineral.
- Though it contains iron, it does not fit the classification of oxide ores.
4. Siderite (FeCO3)
- Siderite is another non-oxide iron mineral, classified as a carbonate ore.
- It contains iron in the form of iron carbonate, thus falling outside the oxide ore category.
Conclusion
In summary, while both hematite and magnetite are oxide ores of iron, hematite stands out as the most recognized and widely used example. It is critical for industries and is the correct answer in the context of identifying oxide ores of iron.
Iron ores are primarily classified based on their chemical composition. Among them, oxide ores are characterized by the presence of iron combined with oxygen.
Examples of Oxide Ores
1. Hematite (Fe2O3)
- Hematite is a major source of iron and is recognized as one of the most important iron ores.
- It consists mainly of ferric oxide and appears in colors ranging from reddish-brown to black.
- Hematite is commonly found in sedimentary rocks and is mined extensively due to its high iron content.
2. Magnetite (Fe3O4)
- While also an oxide ore, magnetite is less commonly highlighted as the primary example in some contexts.
- It contains both ferrous and ferric oxide, and is magnetic, which differentiates it from hematite.
3. Pyrite (FeS2)
- Pyrite, also known as "fool's gold," is not an oxide ore; it is a sulfide mineral.
- Though it contains iron, it does not fit the classification of oxide ores.
4. Siderite (FeCO3)
- Siderite is another non-oxide iron mineral, classified as a carbonate ore.
- It contains iron in the form of iron carbonate, thus falling outside the oxide ore category.
Conclusion
In summary, while both hematite and magnetite are oxide ores of iron, hematite stands out as the most recognized and widely used example. It is critical for industries and is the correct answer in the context of identifying oxide ores of iron.
Which of the following reagents is commonly used to test for the presence of Fe2+ ions?- a)Sodium hydroxide (NaOH)
- b)Ammonium hydroxide (NH4OH)
- c)Silver nitrate (AgNO3)
- d)Barium chloride (BaCl2)
Correct answer is option 'B'. Can you explain this answer?
Which of the following reagents is commonly used to test for the presence of Fe2+ ions?
a)
Sodium hydroxide (NaOH)
b)
Ammonium hydroxide (NH4OH)
c)
Silver nitrate (AgNO3)
d)
Barium chloride (BaCl2)
|
|
Deepak Iyer answered |
Ammonium hydroxide is commonly used to test for the presence of Fe2+ ions. When ammonium hydroxide is added to a solution containing Fe2+ ions, a light green precipitate of iron(II) hydroxide [Fe(OH)2] is formed. This precipitation reaction is a characteristic test for Fe2+ ions.
In the oxidation of Fe2+ ions to Fe3+ ions, the number of electrons gained by each Fe3+ ion is:- a)1
- b)2
- c)3
- d)4
Correct answer is option 'B'. Can you explain this answer?
In the oxidation of Fe2+ ions to Fe3+ ions, the number of electrons gained by each Fe3+ ion is:
a)
1
b)
2
c)
3
d)
4
|
|
Deepak Iyer answered |
In the oxidation of Fe2+ ions to Fe3+ ions, each Fe3+ ion gains 2 electrons. This process involves the transfer of electrons from Fe2+ to an oxidizing agent, resulting in the formation of Fe3+ ions.
Which of the following tests can be used to distinguish between Fe2+ and Fe3+ ions?- a)Flame test
- b)Solubility test
- c)Precipitation test
- d)Redox titration
Correct answer is option 'D'. Can you explain this answer?
Which of the following tests can be used to distinguish between Fe2+ and Fe3+ ions?
a)
Flame test
b)
Solubility test
c)
Precipitation test
d)
Redox titration
|
Chioma Eze answered |
Redox Titration to Distinguish between Fe2+ and Fe3+ ions:
To distinguish between Fe2+ and Fe3+ ions, a redox titration can be used. This method relies on the difference in oxidation states of the two ions.
Procedure:
- In this titration, a known concentration of a reducing agent, such as a solution of potassium permanganate (KMnO4), is added to a solution containing either Fe2+ or Fe3+ ions.
- The reaction between the reducing agent and the iron ions will result in a color change, which can be used to determine the endpoint of the titration.
Distinguishing Fe2+ and Fe3+ ions:
- Fe2+ ions are easily oxidized to Fe3+ ions in the presence of an oxidizing agent like KMnO4. Therefore, if the solution turns pink or purple (indicating the formation of Mn2+ ions) during the titration, it suggests the presence of Fe2+ ions.
- Fe3+ ions, on the other hand, cannot be further oxidized by KMnO4. If the solution remains colorless after the addition of the KMnO4 solution, it indicates the presence of Fe3+ ions.
Conclusion:
- By observing the color change during the redox titration, one can distinguish between Fe2+ and Fe3+ ions based on their different oxidation states and reactivity towards the oxidizing agent.
Copper is primarily extracted from which of the following ores?- a)Malachite
- b)Hematite
- c)Bauxite
- d)Graphite
Correct answer is option 'A'. Can you explain this answer?
Copper is primarily extracted from which of the following ores?
a)
Malachite
b)
Hematite
c)
Bauxite
d)
Graphite
|
|
Deepak Iyer answered |
Copper is primarily extracted from copper ores, and one of the commonly occurring copper ores is malachite. Malachite is a green mineral that contains copper carbonate. It is often found in association with other copper minerals and is an important source of copper.
The process used to convert iron(III) oxide into iron metal is called:- a)Reduction
- b)Oxidation
- c)Calcination
- d)Electrolysis
Correct answer is option 'A'. Can you explain this answer?
The process used to convert iron(III) oxide into iron metal is called:
a)
Reduction
b)
Oxidation
c)
Calcination
d)
Electrolysis
|
|
Deepak Iyer answered |
The process used to convert iron(III) oxide (Fe2O3) into iron metal is called reduction. Reduction involves the removal of oxygen from a compound.
What property of iron makes it suitable for the production of magnets?- a)High melting point
- b)Brittle nature
- c)Magnetic property
- d)Low electrical conductivity
Correct answer is option 'C'. Can you explain this answer?
What property of iron makes it suitable for the production of magnets?
a)
High melting point
b)
Brittle nature
c)
Magnetic property
d)
Low electrical conductivity
|
|
Deepak Iyer answered |
Iron is a ferromagnetic material, meaning it possesses a natural magnetic property. Due to this property, iron is widely used in the production of magnets, electromagnets, and magnetic storage devices. The magnetic property of iron allows it to be easily magnetized and demagnetized.
Which of the following processes is commonly used for the extraction of copper from sulphide ores?- a)Froth flotation
- b)Roasting
- c)Leaching
- d)Electrorefining
Correct answer is option 'A'. Can you explain this answer?
Which of the following processes is commonly used for the extraction of copper from sulphide ores?
a)
Froth flotation
b)
Roasting
c)
Leaching
d)
Electrorefining
|
|
Deepak Iyer answered |
Froth flotation is a commonly used process for the extraction of copper from sulphide ores. In this process, the ore is crushed and ground to a fine powder. It is then mixed with water and various chemicals, including froth collectors and froth stabilizers. Air is blown into the mixture, causing the copper minerals to float on the surface in the form of a froth, which can be skimmed off.
Which of the following equations represents the reduction of iron ore using carbon monoxide?- a)Fe2O3 + 3CO → 2Fe + 3CO2
- b)Fe2O3 + 3CO → 3Fe + 2CO2
- c)FeO + CO → Fe + CO2
- d)Fe2O3 + CO → 2Fe + CO2
Correct answer is option 'B'. Can you explain this answer?
Which of the following equations represents the reduction of iron ore using carbon monoxide?
a)
Fe2O3 + 3CO → 2Fe + 3CO2
b)
Fe2O3 + 3CO → 3Fe + 2CO2
c)
FeO + CO → Fe + CO2
d)
Fe2O3 + CO → 2Fe + CO2
|
|
Deepak Iyer answered |
This equation represents the reduction of iron ore (Fe2O3) using carbon monoxide (CO). The reaction produces three moles of iron and two moles of carbon dioxide.
Copper(II) oxide can be reduced to copper by which of the following gases?- a)Oxygen
- b)Nitrogen
- c)Carbon dioxide
- d)Carbon monoxide
Correct answer is option 'D'. Can you explain this answer?
Copper(II) oxide can be reduced to copper by which of the following gases?
a)
Oxygen
b)
Nitrogen
c)
Carbon dioxide
d)
Carbon monoxide
|
|
Deepak Iyer answered |
Copper(II) oxide can be reduced to copper by carbon monoxide gas in the presence of heat. This is known as a thermite reaction. Carbon monoxide acts as a reducing agent, donating oxygen to copper(II) oxide and converting it into copper metal.
Permallory is an alloy used in:- a)Electrical wires
- b)Aircraft construction
- c)Dental fillings
- d)Magnetic materials
Correct answer is option 'D'. Can you explain this answer?
Permallory is an alloy used in:
a)
Electrical wires
b)
Aircraft construction
c)
Dental fillings
d)
Magnetic materials
|
|
Deepak Iyer answered |
Permallory is an alloy used in the production of magnetic materials, such as permanent magnets.
Soft solder is mainly composed of:- a)Lead and tin
- b)Copper and zinc
- c)Copper and tin
- d)Zinc and tin
Correct answer is option 'C'. Can you explain this answer?
Soft solder is mainly composed of:
a)
Lead and tin
b)
Copper and zinc
c)
Copper and tin
d)
Zinc and tin
|
|
Deepak Iyer answered |
Soft solder is primarily composed of tin and lead, used for joining metals together.
Alnico is an alloy commonly used in the production of:- a)Jewelry
- b)Kitchen utensils
- c)Permanent magnets
- d)Musical instruments
Correct answer is option 'C'. Can you explain this answer?
Alnico is an alloy commonly used in the production of:
a)
Jewelry
b)
Kitchen utensils
c)
Permanent magnets
d)
Musical instruments
|
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Deepak Iyer answered |
Alnico is an alloy used for making permanent magnets, commonly found in speakers and electric motors.
Copper is a good conductor of electricity due to:- a)Its low density
- b)Its high melting point
- c)The presence of free electrons in its structure
- d)Its resistance to corrosion
Correct answer is option 'C'. Can you explain this answer?
Copper is a good conductor of electricity due to:
a)
Its low density
b)
Its high melting point
c)
The presence of free electrons in its structure
d)
Its resistance to corrosion
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Deepak Iyer answered |
Copper is an excellent conductor of electricity because of the presence of free electrons in its atomic structure. Copper has one valence electron in its outer shell, which is loosely held by the nucleus. These electrons are easily mobilized and can move freely through the lattice, allowing for efficient conduction of electricity.
Which of the following properties makes steel an excellent material for reinforcement in concrete structures?- a)High electrical conductivity
- b)Resistance to corrosion
- c)Low density
- d)Brittleness
Correct answer is option 'B'. Can you explain this answer?
Which of the following properties makes steel an excellent material for reinforcement in concrete structures?
a)
High electrical conductivity
b)
Resistance to corrosion
c)
Low density
d)
Brittleness
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Deepak Iyer answered |
Steel is commonly used as reinforcement in concrete structures due to its high tensile strength and resistance to corrosion. Concrete is strong in compression but weak in tension. By incorporating steel reinforcement, the composite material becomes capable of withstanding both compression and tension, resulting in more durable and long-lasting structures.
What is the major advantage of using steel in the manufacturing industry?- a)Steel is highly ductile.
- b)Steel is chemically inert.
- c)Steel can be easily welded and formed.
- d)Steel has a low melting point.
Correct answer is option 'C'. Can you explain this answer?
What is the major advantage of using steel in the manufacturing industry?
a)
Steel is highly ductile.
b)
Steel is chemically inert.
c)
Steel can be easily welded and formed.
d)
Steel has a low melting point.
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Deepak Iyer answered |
One of the major advantages of using steel in the manufacturing industry is its excellent weldability and formability. Steel can be easily joined using various welding techniques, allowing for the fabrication of complex structures. Additionally, steel can be formed into different shapes and sizes through processes such as rolling, forging, and bending, providing versatility in manufacturing applications.
Which of the following compounds is commonly used as an oxidizing agent in the preparation of copper(II) tetraoxosulphate(VI)?- a)Hydrochloric acid
- b)Sulphuric acid
- c)Nitric acid
- d)Acetic acid
Correct answer is option 'C'. Can you explain this answer?
Which of the following compounds is commonly used as an oxidizing agent in the preparation of copper(II) tetraoxosulphate(VI)?
a)
Hydrochloric acid
b)
Sulphuric acid
c)
Nitric acid
d)
Acetic acid
|
|
Deepak Iyer answered |
Nitric acid (HNO3) is commonly used as an oxidizing agent in the preparation of copper(II) tetraoxosulphate(VI). Nitric acid oxidizes copper metal to copper(II) ions, which then react with sulphuric acid to form copper(II) tetraoxosulphate(VI).
The reduction of iron ore to iron metal is achieved by the use of:- a)Carbon monoxide
- b)Oxygen gas
- c)Hydrogen gas
- d)Nitrogen gas
Correct answer is option 'A'. Can you explain this answer?
The reduction of iron ore to iron metal is achieved by the use of:
a)
Carbon monoxide
b)
Oxygen gas
c)
Hydrogen gas
d)
Nitrogen gas
|
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Deepak Iyer answered |
The reduction of iron ore to iron metal is achieved by using carbon monoxide (CO) as the reducing agent. The carbon monoxide reacts with the iron oxide in the ore, reducing it to elemental iron.
The process of converting pig iron into steel by removing impurities is called:- a)Galvanization
- b)Annealing
- c)Quenching
- d)Bessemerization
Correct answer is option 'D'. Can you explain this answer?
The process of converting pig iron into steel by removing impurities is called:
a)
Galvanization
b)
Annealing
c)
Quenching
d)
Bessemerization
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Deepak Iyer answered |
Bessemerization is the process of converting pig iron into steel by removing impurities, such as carbon, silicon, and phosphorus. This process involves blowing air through the molten pig iron.
The molten iron obtained from the blast furnace is called:- a)Pig iron
- b)Wrought iron
- c)Cast iron
- d)Steel
Correct answer is option 'A'. Can you explain this answer?
The molten iron obtained from the blast furnace is called:
a)
Pig iron
b)
Wrought iron
c)
Cast iron
d)
Steel
|
|
Deepak Iyer answered |
The molten iron obtained from the blast furnace is called pig iron. It contains a high percentage of carbon and other impurities and is brittle in nature.
Which of the following is a common use of cast iron?- a)Making cutlery and utensils
- b)Structural supports and beams
- c)Electrical wiring
- d)Automotive bodies and engine blocks
Correct answer is option 'D'. Can you explain this answer?
Which of the following is a common use of cast iron?
a)
Making cutlery and utensils
b)
Structural supports and beams
c)
Electrical wiring
d)
Automotive bodies and engine blocks
|
|
Deepak Iyer answered |
Cast iron is commonly used for making automotive bodies and engine blocks. It has excellent casting properties, high wear resistance, and good heat retention, making it suitable for engine components that operate under high temperatures and mechanical stress.
Which of the following is an example of an alloy?- a)Iron
- b)Copper
- c)Gold
- d)Bronze
Correct answer is option 'D'. Can you explain this answer?
Which of the following is an example of an alloy?
a)
Iron
b)
Copper
c)
Gold
d)
Bronze
|
|
Deepak Iyer answered |
Bronze is an example of an alloy, as it is a mixture of copper and tin.
Which of the following alloys contains copper as one of its major components?- a)Stainless steel
- b)Bronze
- c)Cast iron
- d)Aluminum alloy
Correct answer is option 'B'. Can you explain this answer?
Which of the following alloys contains copper as one of its major components?
a)
Stainless steel
b)
Bronze
c)
Cast iron
d)
Aluminum alloy
|
|
Deepak Iyer answered |
Bronze is an alloy that contains copper as one of its major components. It is composed primarily of copper, with the addition of other elements, such as tin, aluminum, or nickel. Bronze is known for its strength, durability, and resistance to corrosion, making it suitable for various applications like statues, musical instruments, and bearings.
Which form of iron is produced by refining pig iron?- a)Wrought iron
- b)Cast iron
- c)Steel
- d)Pig iron
Correct answer is option 'A'. Can you explain this answer?
Which form of iron is produced by refining pig iron?
a)
Wrought iron
b)
Cast iron
c)
Steel
d)
Pig iron
|
|
Deepak Iyer answered |
Wrought iron is produced by refining pig iron. The refining process involves removing impurities, primarily carbon, from pig iron through a process called puddling. Wrought iron is relatively pure and has a fibrous structure, making it malleable and ductile.
Which of the following is a common use of copper in everyday life?- a)Production of gasoline
- b)Manufacturing of glass
- c)Construction of electrical wires
- d)Food preservation
Correct answer is option 'C'. Can you explain this answer?
Which of the following is a common use of copper in everyday life?
a)
Production of gasoline
b)
Manufacturing of glass
c)
Construction of electrical wires
d)
Food preservation
|
|
Deepak Iyer answered |
Copper is commonly used in the construction of electrical wires due to its excellent electrical conductivity. Copper wires are preferred for transmitting electricity because they offer low resistance and minimize energy loss.
Which of the following is NOT a characteristic of Fe3+ ions?- a)Paramagnetic
- b)High reactivity
- c)Forms complex ions
- d)Blue color in solution
Correct answer is option 'D'. Can you explain this answer?
Which of the following is NOT a characteristic of Fe3+ ions?
a)
Paramagnetic
b)
High reactivity
c)
Forms complex ions
d)
Blue color in solution
|
|
Deepak Iyer answered |
Fe3+ ions do not exhibit a blue color in solution. They are typically pale yellow or orange-brown in color. Blue color in solution is associated with certain other transition metal ions like Cu2+.
Alloys are important in metallurgy because they:- a)Can be recycled easily
- b)Have lower production costs
- c)Possess unique and desirable properties
- d)Are more abundant than pure metals
Correct answer is option 'B'. Can you explain this answer?
Alloys are important in metallurgy because they:
a)
Can be recycled easily
b)
Have lower production costs
c)
Possess unique and desirable properties
d)
Are more abundant than pure metals
|
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Deepak Iyer answered |
Brass is a commonly used alloy for making musical instruments due to its acoustic properties.
Which of the following is an example of a non-ferrous alloy?- a)Brass
- b)Cast iron
- c)Steel
- d)Wrought iron
Correct answer is option 'A'. Can you explain this answer?
Which of the following is an example of a non-ferrous alloy?
a)
Brass
b)
Cast iron
c)
Steel
d)
Wrought iron
|
|
Deepak Iyer answered |
Brass is a non-ferrous alloy composed of copper and zinc.
The main reducing agent used in the extraction of iron from its ore is:- a)Carbon monoxide
- b)Oxygen gas
- c)Hydrogen gas
- d)Nitrogen gas
Correct answer is option 'A'. Can you explain this answer?
The main reducing agent used in the extraction of iron from its ore is:
a)
Carbon monoxide
b)
Oxygen gas
c)
Hydrogen gas
d)
Nitrogen gas
|
|
Deepak Iyer answered |
Carbon monoxide (CO) is the main reducing agent used in the extraction of iron from its ore. It reacts with the iron oxide to remove oxygen and obtain elemental iron.
Stainless steel is primarily composed of:- a)Iron and carbon
- b)Iron and nickel
- c)Iron and chromium
- d)Iron and aluminum
Correct answer is option 'C'. Can you explain this answer?
Stainless steel is primarily composed of:
a)
Iron and carbon
b)
Iron and nickel
c)
Iron and chromium
d)
Iron and aluminum
|
|
Deepak Iyer answered |
Stainless steel is primarily composed of iron and chromium, which provide its corrosion resistance.
Copper reacts with oxygen in the presence of moisture to form a green layer. What is this layer called?- a)Oxide layer
- b)Carbonate layer
- c)Sulphate layer
- d)Patina layer
Correct answer is option 'D'. Can you explain this answer?
Copper reacts with oxygen in the presence of moisture to form a green layer. What is this layer called?
a)
Oxide layer
b)
Carbonate layer
c)
Sulphate layer
d)
Patina layer
|
|
Deepak Iyer answered |
When copper reacts with oxygen in the presence of moisture, it forms a greenish layer called the patina layer. This layer is composed of various copper compounds, such as copper hydroxide and copper carbonate, and it acts as a protective coating against further corrosion.
Which of the following is a confirmatory test for the presence of Fe3+ ions?- a)Sodium hydroxide test
- b)Ammonium hydroxide test
- c)Potassium ferrocyanide test
- d)Barium chloride test
Correct answer is option 'C'. Can you explain this answer?
Which of the following is a confirmatory test for the presence of Fe3+ ions?
a)
Sodium hydroxide test
b)
Ammonium hydroxide test
c)
Potassium ferrocyanide test
d)
Barium chloride test
|
|
Deepak Iyer answered |
The potassium ferrocyanide test is a confirmatory test for the presence of Fe3+ ions. When potassium ferrocyanide is added to a solution containing Fe3+ ions, a deep blue precipitate of iron(III) ferrocyanide (Prussian blue) is formed.
Fe3+ ions can be reduced to Fe2+ ions by:- a)Adding sodium hydroxide (NaOH)
- b)Adding hydrogen peroxide (H2O2)
- c)Adding sodium carbonate (Na2CO3)
- d)Adding a reducing agent like zinc (Zn)
Correct answer is option 'D'. Can you explain this answer?
Fe3+ ions can be reduced to Fe2+ ions by:
a)
Adding sodium hydroxide (NaOH)
b)
Adding hydrogen peroxide (H2O2)
c)
Adding sodium carbonate (Na2CO3)
d)
Adding a reducing agent like zinc (Zn)
|
|
Deepak Iyer answered |
Fe3+ ions can be reduced to Fe2+ ions by adding a reducing agent. Zinc (Zn) is commonly used as a reducing agent in this context. When zinc is added to a solution containing Fe3+ ions, the zinc reacts with Fe3+ ions, transferring electrons and reducing Fe3+ to Fe2+.
Duralumin is an alloy that contains:- a)Aluminum and zinc
- b)Aluminum and copper
- c)Aluminum and magnesium
- d)Aluminum and iron
Correct answer is option 'C'. Can you explain this answer?
Duralumin is an alloy that contains:
a)
Aluminum and zinc
b)
Aluminum and copper
c)
Aluminum and magnesium
d)
Aluminum and iron
|
|
Deepak Iyer answered |
Duralumin is an aluminum-based alloy that contains copper and magnesium, known for its lightweight and high strength.
Which of the following best defines an alloy?- a)A pure substance composed of a single element.
- b)A mixture of two or more elements, with at least one being a metal.
- c)A compound formed by the reaction of a metal with a non-metal.
- d)A mixture of two or more non-metals.
Correct answer is option 'B'. Can you explain this answer?
Which of the following best defines an alloy?
a)
A pure substance composed of a single element.
b)
A mixture of two or more elements, with at least one being a metal.
c)
A compound formed by the reaction of a metal with a non-metal.
d)
A mixture of two or more non-metals.
|
|
Deepak Iyer answered |
Alloys are mixtures of two or more elements, with at least one being a metal.
When Fe2+ ions react with potassium manganate(VII) (KMnO4) in an acidic medium, the Fe2+ ions are oxidized to Fe3+ ions and the MnO4- ions are reduced to:- a)MnO2
- b)Mn2O3
- c)MnO4
- d)Mn2O7
Correct answer is option 'A'. Can you explain this answer?
When Fe2+ ions react with potassium manganate(VII) (KMnO4) in an acidic medium, the Fe2+ ions are oxidized to Fe3+ ions and the MnO4- ions are reduced to:
a)
MnO2
b)
Mn2O3
c)
MnO4
d)
Mn2O7
|
|
Deepak Iyer answered |
When Fe2+ ions react with potassium manganate(VII) (KMnO4) in an acidic medium, Fe2+ ions are oxidized to Fe3+ ions, and the MnO4- ions are reduced to brown manganese dioxide (MnO2). This reaction is commonly known as the "iodometric titration."
Which of the following color changes is observed when Fe2+ ions are oxidized to Fe3+ ions?- a)Colorless to pale green
- b)Pale green to orange-brown
- c)Orange-brown to colorless
- d)Colorless to blue
Correct answer is option 'B'. Can you explain this answer?
Which of the following color changes is observed when Fe2+ ions are oxidized to Fe3+ ions?
a)
Colorless to pale green
b)
Pale green to orange-brown
c)
Orange-brown to colorless
d)
Colorless to blue
|
|
Deepak Iyer answered |
When Fe2+ ions are oxidized to Fe3+ ions, the color of the solution changes from pale green to orange-brown. This color change is due to the formation of the Fe3+ ion, which has an orange-brown color in solution.
Which form of iron has the highest carbon content?- a)Wrought iron
- b)Cast iron
- c)Steel
- d)Pig iron
Correct answer is option 'D'. Can you explain this answer?
Which form of iron has the highest carbon content?
a)
Wrought iron
b)
Cast iron
c)
Steel
d)
Pig iron
|
|
Deepak Iyer answered |
Pig iron is the form of iron that is obtained directly from the blast furnace. It has a high carbon content, typically around 3-4%, along with other impurities. Pig iron is not suitable for most applications and requires further processing to produce useful iron and steel products.
Chapter doubts & questions for First Transition Series Elements - Chemistry for JAMB 2025 is part of JAMB exam preparation. The chapters have been prepared according to the JAMB exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for JAMB 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
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Chemistry for JAMB
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