125876 + Interview Questions in General QA Page 572 InterviewSolution

28551.	If carbon dioxide is dissolved in water it produces……………..acid A) Carbonic B) Hydrochloric C) Chlorous D) Sulphuric
Answer» Correct option is A) Carbonic

Discussion

28552.	Match the following : a) Horn silver — i) MnO2 b) Pyrolusite — ii) AgClc) Zincite — iii) NaCl d) Rock salt — iv) ZnO A) a → i, b→ii, c → iii, d →iv B) a → iv, b → iii, c → ii, d → i C) a → ii, b → i, c → iv, d → iii D) a → iv, b → ii, c → i, d→iii
Answer» C) a → ii, b → i, c → iv, d → iii

Discussion

28553.	The ore of mercury is …………. A) Galena B) Cinnabar C.) Gypsum D) Zincite
Answer» Correct option is B) Cinnabar

Discussion

28554.	Match the following: a) Horn silver — i) KCl. MgCl2 . 6H2Ob) Haematite — ii) AgCl c) Cinnabar — iii) Fe2O3 d) Camalite — iv) Hgs A) a → ii, b → iii, c→ iv, d → i B) a→ i, b → ii, c → iii, d → iv C) a → iv, b → iii, c → ii, d → i D) a → iv, b → i, c → di, d → iii
Answer» A) a → ii, b → iii, c→ iv, d → i

Discussion

28555.	What are the examples of corrosion?
Answer» 1. Rusting of iron. 2. Tarnishing of silver. 3. Development of green coating on copper (CuCO₃). 4. Green coating on Bronze.

28555.

What are the examples of corrosion?

Answer»

1. Rusting of iron.

2. Tarnishing of silver.

3. Development of green coating on copper (CuCO₃).

4. Green coating on Bronze.

Discussion

28556.	Explain the process involved in corrosion.
Answer» 1) Corrosion is an electrochemical phenomenon. 2) In corrosion, a metal is oxidised by loss of electrons generally to oxygen and results in the formation of oxides. 3) During corrosion at a particular spot on the surface of an object made of iron, oxidation takes place and that spot behaves as anode. Anode : 2 Fe_(s) → 2 Fe²⁺ + 4e^- 4) Electrons released at this anodic spot move through the metal and go to another spot and reduce oxygen at that spot in the presence of H+. 5) This spot behaves as cathode. Cathode : O_2(g) + 4 H⁺_(aq) + 4e^- → 2H₂O_(I) Net reaction : 2 Fe_(s) + O_2(g) + 4 H⁺_(aq) → 2 Fe²⁺_(aq) + 2 H₂O_(I) 6) The ferrous ions are further oxidised by atmospheric oxygen to ferric ions which come out as rust in the form of hydrated ferric oxide (Fe₂O₃ . XH₂O) and with further production of hydrogen ions.

28556.

Explain the process involved in corrosion.

Answer»

1) Corrosion is an electrochemical phenomenon.

2) In corrosion, a metal is oxidised by loss of electrons generally to oxygen and results in the formation of oxides.

3) During corrosion at a particular spot on the surface of an object made of iron, oxidation takes place and that spot behaves as anode.

Anode : 2 Fe_(s) → 2 Fe²⁺ + 4e^-

4) Electrons released at this anodic spot move through the metal and go to another spot and reduce oxygen at that spot in the presence of H+.

5) This spot behaves as cathode.

Cathode : O_2(g) + 4 H⁺_(aq) + 4e^- → 2H₂O_(I)

Net reaction : 2 Fe_(s) + O_2(g) + 4 H⁺_(aq) → 2 Fe²⁺_(aq) + 2 H₂O_(I)

6) The ferrous ions are further oxidised by atmospheric oxygen to ferric ions which come out as rust in the form of hydrated ferric oxide (Fe₂O₃ . XH₂O) and with further production of hydrogen ions.

Discussion

28557.	Give some examples for corrosion.
Answer» Examples for corrosion : 1. The rusting of iron (Iron oxide) 2. Tarnishing of silver (Silver sulphide) 3. Development of green coating on copper (Copper carbonate) and bronze.

28557.

Give some examples for corrosion.

Answer»

Examples for corrosion :

1. The rusting of iron (Iron oxide)

2. Tarnishing of silver (Silver sulphide)

3. Development of green coating on copper (Copper carbonate) and bronze.

Discussion

28558.	Name the form of carbon used in the blast furnace for the extraction of iron.
Answer» Carbon is used in the form of coke to reduce iron in blast furnace.

Discussion

28559.	Name two metals normally manufactured by the electrolysis of fused compounds.
Answer» Metals with high reactivity can be extracted by electrolysis of their fused compounds. The examples are potassium, sodium and calcium.

Discussion

28560.	Do metals exist in the same form as that we use in our daily life?
Answer» No, they exist as ores and minerals and some may exist in the form of metals.

Discussion

28561.	Write about electrolysis of NaCl.
Answer» 1) Fused NaCl is electrolysed with steel cathode and graphite anode. 2) The metal sodium (Na) will be deposited at cathode and chlorine gas liberates at the anode. At Cathode : 2 Na⁺ + 2e^- → 2 Na At Anode : 2 Cl^- → Cl₂ + 2e^-

28561.

Write about electrolysis of NaCl.

Answer»

1) Fused NaCl is electrolysed with steel cathode and graphite anode.

2) The metal sodium (Na) will be deposited at cathode and chlorine gas liberates at the anode.

At Cathode : 2 Na⁺ + 2e^- → 2 Na

At Anode : 2 Cl^- → Cl₂ + 2e^-

Discussion

28562.	The chemical formula of rust is A) Fe2O3 .XH2O B) FeO C) FeS D) Fe2O5
Answer» Correct option is A) Fe₂O₃ .XH₂O

Discussion

28563.	The formula of rust is…………….. A) Fe2O3 B) FeO C) Fe2O3 . XH2O.D) Fe(OH)3
Answer» C) Fe₂O₃ . XH₂O.

Discussion

28564.	The method used for extraction of metals at the top of the activity series is …………….. A) Simple reduction of their oxides B) Electrolysis of their aqueous solutions C) Electrolysis of their fused compounds D) All of these
Answer» C) Electrolysis of their fused compounds

Discussion

28565.	Where do we use hand picking and washing methods in our daily life ? Give examples. How do you correlate these examples with enrichment of ore?
Answer» Daily life examples for hand picking: 1. Separating mud particles from rice is an example for hand picking because the colour and size of these two are different. 2. Similarly, the ore particles and the impurities are different in one of the properties like colour, size, etc. are separated by hand picking. Daily life examples for washing : 1. We can clean some vegetables like potatoes by controlled flow of water. Less densive impurities are carried away by the flow leaving the more densive potatoes. 2. Similarly, ores are washed with controlled flow of water. Less densive impurities i are carried away by water flow, leaving the more densive ore particles behind.

28565.

Where do we use hand picking and washing methods in our daily life ? Give examples. How do you correlate these examples with enrichment of ore?

Answer»

Daily life examples for hand picking:

1. Separating mud particles from rice is an example for hand picking because the colour and size of these two are different.

2. Similarly, the ore particles and the impurities are different in one of the properties like colour, size, etc. are separated by hand picking.

Daily life examples for washing :

1. We can clean some vegetables like potatoes by controlled flow of water. Less densive impurities are carried away by the flow leaving the more densive potatoes.

2. Similarly, ores are washed with controlled flow of water. Less densive impurities i are carried away by water flow, leaving the more densive ore particles behind.

Discussion

28566.	Match the following: a) Magnesite — i) Ca b) Horn silver — ii) Mg c) Lime stone — iii) Fe d) Haematite — iv) Ag A) a → i, b → ii, c → iii, d → iv B) a → iv, b → iii, c → ii, d → i C) a → ii, b → iv, c → i, d → iiiD) a → iv, b → ii, c → i, d → iii
Answer» C) a → ii, b → iv, c → i, d → iii

Discussion

28567.	Give name and formulae of sulphide ore of lead and mercury.
Answer» a) Sulphide ore of lead is Galena. Its formula is PbS. b) Sulphide ore of mercury is Cinnabar. Its formula is HgS.

28567.

Give name and formulae of sulphide ore of lead and mercury.

Answer»

a) Sulphide ore of lead is Galena. Its formula is PbS.

b) Sulphide ore of mercury is Cinnabar. Its formula is HgS.

Discussion

28568.	What are the uses of thermite reaction?
Answer» Thermite reaction is used to join railings of railway tracks or cracked machine parts.

Discussion

28569.	Which pyrochemical process is useful to convert zinc blende into oxide ore?
Answer» Zinc blende is sulphide ore of zinc. Its formula is ZnS. So it can be converted into oxide ore by heating strongly in excess of air known as roasting. 2 ZnS + 3 O₂ → 2 ZnO + 2 SO₂

28569.

Which pyrochemical process is useful to convert zinc blende into oxide ore?

Answer»

Zinc blende is sulphide ore of zinc. Its formula is ZnS. So it can be converted into oxide ore by heating strongly in excess of air known as roasting.

2 ZnS + 3 O₂ → 2 ZnO + 2 SO₂

Discussion

28570.	Give two examples for corrosion.
Answer» 1) Rusting of iron 2) Green coating on copper.

28570.

Give two examples for corrosion.

Answer»

1) Rusting of iron

2) Green coating on copper.

Discussion

28571.	Predict, what happens in the field of domestic use of metals if alloys were not discovered.
Answer» If alloys were not discovered, 1. All the vessels/utensils made of single metal like iron, copper, aluminium, etc. may be used for cooking purpose. 2. We may face problems like rusting of iron, tarnishing of silver and copper, etc. 3. We may face the problems of corrosion of home appliances. 4. We may face difficulties in cleaning of the vessels due to rusting and tarnishing. 5. Cost of the utensils may be risen, because of less availability of the metals like copper. 6. Using of the plastic ware may be risen for storage due to lack of steel containers. 7. Brass, steel, bronze, etc. utensils are not available to use. 8. Making of jewellary is also difficult.

28571.

Predict, what happens in the field of domestic use of metals if alloys were not discovered.

Answer»

If alloys were not discovered,

1. All the vessels/utensils made of single metal like iron, copper, aluminium, etc. may be used for cooking purpose.

2. We may face problems like rusting of iron, tarnishing of silver and copper, etc.

3. We may face the problems of corrosion of home appliances.

4. We may face difficulties in cleaning of the vessels due to rusting and tarnishing.

5. Cost of the utensils may be risen, because of less availability of the metals like copper.

6. Using of the plastic ware may be risen for storage due to lack of steel containers.

7. Brass, steel, bronze, etc. utensils are not available to use.

8. Making of jewellary is also difficult.

Discussion

28572.	During electrolysis of NaCZ the substances formed at anode and cathode are …………….. A) Na, Cl2 B) Cl2 , Na C) Na2 , Cl D) None of these
Answer» Correct option is B) Cl₂ , Na

Discussion

28573.	Which of the following is the correct formula of Gypsum? A) CuSO4 • 2 H2O B) CaSO4 • ½ H2O C) CuSO4 • 5 H2O D) CaSO4 • 2 H2O
Answer» Correct option is: D) CaSO₄ • 2 H₂O

Discussion

28574.	Write the physical methods used for the concentration of the ore. Explain the method used for concentration of the sulphide ore.
Answer» Physical methods used for the concentration of the ore is, i) Hand Picking ii) Washing iii) Froth floatation iv) Magnetic Separation. Concentration of sulphide ore : 1. Sulphide ore is concentrated by using froth floatation Method. 2. The ore with impurities is timely powdered and kept in water taken in a flotation cell. 3. Air under pressure is blown to produce froth in water. 4. Froth so produced, taken the ore particles to the surface whereas impurities settle at the bottom. 5. Froth is separated and washed to get ore particles.

28574.

Write the physical methods used for the concentration of the ore. Explain the method used for concentration of the sulphide ore.

Answer»

Physical methods used for the concentration of the ore is,

i) Hand Picking

ii) Washing

iii) Froth floatation

iv) Magnetic Separation.

Concentration of sulphide ore :

1. Sulphide ore is concentrated by using froth floatation Method.

2. The ore with impurities is timely powdered and kept in water taken in a flotation cell.

3. Air under pressure is blown to produce froth in water.

4. Froth so produced, taken the ore particles to the surface whereas impurities settle at the bottom.

5. Froth is separated and washed to get ore particles.

Discussion

28575.	The method used to convert magnesite to oxide ore is …………….. A) Roasting B) Calcination C) Smelting D) All of these
Answer» B) Calcination

Discussion

28576.	Define mineral. Mention any two ores of ‘magnesium’.
Answer» 1) Minerals : The elements or compounds of the metals which occur in nature in the earth crust are called ‘minerals’. 2) Two ores of magnesium : Magnesite – MgCO₃ Carnalite – KCl MgCl₂ 6H₂O

28576.

Define mineral. Mention any two ores of ‘magnesium’.

Answer»

1) Minerals :

The elements or compounds of the metals which occur in nature in the earth crust are called ‘minerals’.

2) Two ores of magnesium :

Magnesite – MgCO₃

Carnalite – KCl MgCl₂ 6H₂O

Discussion

28577.	Is silver mineral or ore? Justify your answer.
Answer» Silver is neither mineral nor ore. It is a metal.

Discussion

28578.	Have you ever heard the words like ore, mineral and metallurgy?
Answer» Yes, these words are related to extraction of metals

Discussion

28579.	The oil used in the froth floatation process is…………….. A) kerosene oil B) pine oil C) coconut oil D) olive oil
Answer» Correct option is B) pine oil

Discussion

28580.	Give an example with the chemical equation for the reduction of ores using more reactive metals.
Answer» The reaction of Iron oxide with aluminium. Fe₂ O₃ + 2Al → 2Fe + Al₂ O₃ + Heat (Or) Reaction of Titanium Chloride with Magnesium. TiCl₄ + 2Mg → Ti + 2MgCl₂ (Or) Reaction of Titanium Chloride with Sodium. HCl₄ + 4Na → Ti + 4NaCl (Or) Reaction of Cromium oxide with aluminium. Cr₂ O₃ + 2Al → 2Cr + Al₂ O₃ + Heat

28580.

Give an example with the chemical equation for the reduction of ores using more reactive metals.

Answer»

The reaction of Iron oxide with aluminium.

Fe₂ O₃ + 2Al → 2Fe + Al₂ O₃ + Heat

(Or)

Reaction of Titanium Chloride with Magnesium.

TiCl₄ + 2Mg → Ti + 2MgCl₂

(Or)

Reaction of Titanium Chloride with Sodium.

HCl₄ + 4Na → Ti + 4NaCl

(Or)

Reaction of Cromium oxide with aluminium.

Cr₂ O₃ + 2Al → 2Cr + Al₂ O₃ + Heat

Discussion

28581.	The ores of metals in the middle of activity series generally present in the form of…………….. i) Oxides ii) Chlorides iii) Sulphates iv) SulphidesA) (i) and (ii) B) (i) and (iii) C) (ii) and (iii) D) (i) and (iv)
Answer» D) (i) and (iv)

Discussion

28582.	The oil used in the froth flotation process is A) kerosene oil B) pine oil C) coconut oil D) olive oil
Answer» Correct option is: B) pine oil

Discussion

28583.	What is froth flotation ?
Answer» Air under pressure is blown to produce froth in water is called froth flotation.

Discussion

28584.	What is an ore? On what basis a mineral is chosen as an ore?
Answer» Ore : A mineral from which a metal can be extracted economically and conveniently is called ore. A mineral is chosen as an ore if the mineral is economical and profitable to extract. Example: Aluminium is the common metal in the Earth’s crust in all sorts of minerals. It is economically feasible and profitable to extract from bauxite which contains 50-70% of aluminium oxide.

28584.

What is an ore? On what basis a mineral is chosen as an ore?

Answer»

Ore :

A mineral from which a metal can be extracted economically and conveniently is called ore. A mineral is chosen as an ore if the mineral is economical and profitable to extract.

Example:

Aluminium is the common metal in the Earth’s crust in all sorts of minerals. It is economically feasible and profitable to extract from bauxite which contains 50-70% of aluminium oxide.

Discussion

28585.	What are the ores of iron?
Answer» Haematite (Fe₂ O₃), Magnetite (Fe₃ O₄).

Discussion

28586.	Name two ores of calcium and give their formulae.
Answer» The ores of calcium are 1. Gypsum (CaSO₄ • 2H₂O) 2. Limestone (CaCO₃)

28586.

Name two ores of calcium and give their formulae.

Answer»

The ores of calcium are

1. Gypsum (CaSO₄ • 2H₂O)

2. Limestone (CaCO₃)

Discussion

28587.	The most abundant metal in the earth’s crust is …………….. A) silver B) aluminium C) zinc D) iron
Answer» B) aluminium

Discussion

28588.	The purpose of smelting an ore is to …….. it. A) Oxidise B) Reduce C) Neutralise D) None of these
Answer» Correct option is: B) Reduce

Discussion

28589.	What metals can we get from the ores mentioned in the Table – 1?
Answer» The metals are Aluminium (Al), Copper (Cu), Magnesium (Mg), Silver (Ag), Manganese (Mn), Iron (Fe), Zinc (Zn), Sodium (Na), Mercury (Hg), Lead (Pb), Calcium (Ca).

Discussion

28590.	Write the names of any two ores of iron.
Answer» The names of two ores of iron : 1. Haematite (Fe₂O₃) 2. Magnetite (Fe₃O₄).

28590.

Write the names of any two ores of iron.

Answer»

The names of two ores of iron :

1. Haematite (Fe₂O₃)

2. Magnetite (Fe₃O₄).

Discussion

28591.	The elements or compounds of the metals which occur in nature in the earth crust are called ……………… A) ores B) minerals C) gangue D) slag
Answer» Correct option is B) minerals

Discussion

28592.	What is Micelle?
Answer» Micelle: A spherical aggregate of soap molecules in the soap solution in water is called a micelle.

Discussion

28593.	How do metals occur in nature ? Give examples to any two types of minerals.
Answer» 1. The earth’s crust is the major source of metals. 2. Sea water also contains some soluble salts such as sodium chloride and magnesium chloride etc. 3. Some metals like gold (Au), silver (Ag) and copper (Cu) are available in nature in free state as they are least reactive. 4. Other metals are found in nature in the combined form due to their more reactivity. 5. The elements or compounds of the metals which occur in nature in the earth’s crust are called minerals. Examples : Minerals in oxide form : Bauxite, Zincite, Magnetite, etc. Minerals in sulphide form : Copper iron pyretes, Galena, etc.

28593.

How do metals occur in nature ? Give examples to any two types of minerals.

Answer»

1. The earth’s crust is the major source of metals.

2. Sea water also contains some soluble salts such as sodium chloride and magnesium chloride etc.

3. Some metals like gold (Au), silver (Ag) and copper (Cu) are available in nature in free state as they are least reactive.

4. Other metals are found in nature in the combined form due to their more reactivity.

5. The elements or compounds of the metals which occur in nature in the earth’s crust are called minerals.

Examples :

Minerals in oxide form :

Bauxite, Zincite, Magnetite, etc.

Minerals in sulphide form :

Copper iron pyretes, Galena, etc.

Discussion

28594.	How are the metals present in nature?
Answer» Some metals like gold (Au), silver (Ag) and copper (Cu) are available in nature in free sjate. Other metals mostly are found in nature in the combined form.

Discussion

28595.	What is Metallurgy?
Answer» Metallurgy is the process of extraction of metals from their ores and the preparation of alloys.

Discussion

28596.	What are minerals ?
Answer» The elements or compounds of the metals which occur in nature in the earth’s crust are called minerals.

Discussion

28597.	Why few metals are found in free state in nature ?
Answer» Metals like gold (Au), silver (Ag) and copper (Cu) are available in nature in a free state as they are least reactive.

Discussion

28598.	High reactivityModerate reactivityLow reactivityK, Na, Ca, Mg, AlZn, Fe, Pb, CuAg, AuObserve the table and answer the following questions. i) Which of the above metals found even in free state in nature ? ii) Which of the above metal’s ore are concentrated by using magnetic separation?
Answer» i) Ag, Au. ii) Fe.

28598.

High reactivityModerate reactivityLow reactivityK, Na, Ca, Mg, AlZn, Fe, Pb, CuAg, AuObserve the table and answer the following questions. i) Which of the above metals found even in free state in nature ? ii) Which of the above metal’s ore are concentrated by using magnetic separation?

Answer»

i) Ag, Au.

ii) Fe.

Discussion

28599.	List three metals that are found in nature in uncombined form.
Answer» The three metals that are found in nature in uncombined form are 1. Gold 2. Silver 3. Platinum.

28599.

List three metals that are found in nature in uncombined form.

Answer»

The three metals that are found in nature in uncombined form are

1. Gold

2. Silver

3. Platinum.

Discussion

28600.	The area of a rectangle field is 3584 m2 and its length is 64 m. A boy runs around the field at the rate of 6 km/h. How long will he take to go 5 times around it?
Answer» From the question we have, Area of the rectangular field = 3584 m² Length of the rectangular field = 64 m Boy runs around the field at the rate = 6 km/h = ((6 × 1000) / 60) m/min = 100 m/min Breadth of the rectangular field = (area /length) = (3584/ 64) = 56 m ∴perimeter of the field = 2(l + b) units = 2 (64 + 56) = 2 (120) = 240m Total distance covered by the boy = 5 × perimeter of the field = 5 × 240 = 1200m ∴required time to cover the distance of 1200m = (1200/100) = 12min Hence, boy took 12 min to go 5 times around of rectangular field.

28600.

The area of a rectangle field is 3584 m2 and its length is 64 m. A boy runs around the field at the rate of 6 km/h. How long will he take to go 5 times around it?

Answer»

From the question we have,

Area of the rectangular field = 3584 m²

Length of the rectangular field = 64 m

Boy runs around the field at the rate = 6 km/h

= ((6 × 1000) / 60) m/min

= 100 m/min

Breadth of the rectangular field = (area /length)

= (3584/ 64)

= 56 m

∴perimeter of the field = 2(l + b) units

= 2 (64 + 56)

= 2 (120)

= 240m

Total distance covered by the boy = 5 × perimeter of the field

= 5 × 240

= 1200m

∴required time to cover the distance of 1200m = (1200/100) = 12min

Hence, boy took 12 min to go 5 times around of rectangular field.

Discussion

Explore topic-wise InterviewSolutions in .

If carbon dioxide is dissolved in water it produces……………..acid A) Carbonic B) Hydrochloric C) Chlorous D) Sulphuric

Match the following : a) Horn silver — i) MnO2 b) Pyrolusite — ii) AgClc) Zincite — iii) NaCl d) Rock salt — iv) ZnO A) a → i, b→ii, c → iii, d →iv B) a → iv, b → iii, c → ii, d → i C) a → ii, b → i, c → iv, d → iii D) a → iv, b → ii, c → i, d→iii

The ore of mercury is …………. A) Galena B) Cinnabar C.) Gypsum D) Zincite

What are the examples of corrosion?

Explain the process involved in corrosion.

Give some examples for corrosion.

Name the form of carbon used in the blast furnace for the extraction of iron.

Name two metals normally manufactured by the electrolysis of fused compounds.

Do metals exist in the same form as that we use in our daily life?

Write about electrolysis of NaCl.

The chemical formula of rust is A) Fe2O3 .XH2O B) FeO C) FeS D) Fe2O5

The formula of rust is…………….. A) Fe2O3 B) FeO C) Fe2O3 . XH2O.D) Fe(OH)3

The method used for extraction of metals at the top of the activity series is …………….. A) Simple reduction of their oxides B) Electrolysis of their aqueous solutions C) Electrolysis of their fused compounds D) All of these

Where do we use hand picking and washing methods in our daily life ? Give examples. How do you correlate these examples with enrichment of ore?

Match the following: a) Magnesite — i) Ca b) Horn silver — ii) Mg c) Lime stone — iii) Fe d) Haematite — iv) Ag A) a → i, b → ii, c → iii, d → iv B) a → iv, b → iii, c → ii, d → i C) a → ii, b → iv, c → i, d → iiiD) a → iv, b → ii, c → i, d → iii

Give name and formulae of sulphide ore of lead and mercury.

What are the uses of thermite reaction?

Which pyrochemical process is useful to convert zinc blende into oxide ore?

Give two examples for corrosion.

Predict, what happens in the field of domestic use of metals if alloys were not discovered.

During electrolysis of NaCZ the substances formed at anode and cathode are …………….. A) Na, Cl2 B) Cl2 , Na C) Na2 , Cl D) None of these

Which of the following is the correct formula of Gypsum? A) CuSO4 • 2 H2O B) CaSO4 • ½ H2O C) CuSO4 • 5 H2O D) CaSO4 • 2 H2O

Write the physical methods used for the concentration of the ore. Explain the method used for concentration of the sulphide ore.

The method used to convert magnesite to oxide ore is …………….. A) Roasting B) Calcination C) Smelting D) All of these

Define mineral. Mention any two ores of ‘magnesium’.

Is silver mineral or ore? Justify your answer.

Have you ever heard the words like ore, mineral and metallurgy?

The oil used in the froth floatation process is…………….. A) kerosene oil B) pine oil C) coconut oil D) olive oil

Give an example with the chemical equation for the reduction of ores using more reactive metals.

The ores of metals in the middle of activity series generally present in the form of…………….. i) Oxides ii) Chlorides iii) Sulphates iv) SulphidesA) (i) and (ii) B) (i) and (iii) C) (ii) and (iii) D) (i) and (iv)

The oil used in the froth flotation process is A) kerosene oil B) pine oil C) coconut oil D) olive oil

What is froth flotation ?

What is an ore? On what basis a mineral is chosen as an ore?

What are the ores of iron?

Name two ores of calcium and give their formulae.

The most abundant metal in the earth’s crust is …………….. A) silver B) aluminium C) zinc D) iron

The purpose of smelting an ore is to …….. it. A) Oxidise B) Reduce C) Neutralise D) None of these

What metals can we get from the ores mentioned in the Table – 1?

Write the names of any two ores of iron.

The elements or compounds of the metals which occur in nature in the earth crust are called ……………… A) ores B) minerals C) gangue D) slag

What is Micelle?

How do metals occur in nature ? Give examples to any two types of minerals.

How are the metals present in nature?

What is Metallurgy?

What are minerals ?

Why few metals are found in free state in nature ?

High reactivityModerate reactivityLow reactivityK, Na, Ca, Mg, AlZn, Fe, Pb, CuAg, AuObserve the table and answer the following questions. i) Which of the above metals found even in free state in nature ? ii) Which of the above metal’s ore are concentrated by using magnetic separation?

List three metals that are found in nature in uncombined form.

The area of a rectangle field is 3584 m2 and its length is 64 m. A boy runs around the field at the rate of 6 km/h. How long will he take to go 5 times around it?