7248 + Interview Questions in Chemistry Page 40 InterviewSolution

1951.	What is the process of obtaining crystals of a substance from its solution in water called?
Answer» What is the process of obtaining crystals of a substance from its solution in water called?

Discussion

1952.	As seen in the figure, two nails are carefully dipped in copper sulphate solution with the help of threads. What will happen when the nails are removed after half an hour?
Answer» As seen in the figure, two nails are carefully dipped in copper sulphate solution with the help of threads. What will happen when the nails are removed after half an hour?

1952.

As seen in the figure, two nails are carefully dipped in copper sulphate solution with the help of threads. What will happen when the nails are removed after half an hour?

Answer»

As seen in the figure, two nails are carefully dipped in copper sulphate solution with the help of threads. What will happen when the nails are removed after half an hour?

Discussion

1953.	How do we clean silver or brass articles that have got tarnished?
Answer» How do we clean silver or brass articles that have got tarnished?

Discussion

1954.	Question 7.What kind of change is burning of a candle?
Answer» Question 7. What kind of change is burning of a candle?

1954.

Question 7.What kind of change is burning of a candle?

Answer»

Question 7.

What kind of change is burning of a candle?

Discussion

1955.	Why is chromium plating done on many objects such as car parts, bath taps etc.? Why is steel not preferred as a car part or a bath tap?
Answer» Why is chromium plating done on many objects such as car parts, bath taps etc.? Why is steel not preferred as a car part or a bath tap?

Discussion

1956.	It is advised not to throw plastic in garbage dumping area as:
Answer» It is advised not to throw plastic in garbage dumping area as:

Discussion

1957.	A uniform solid cylinder of density 0.8 g/cm3 floats in equilibrium in a combination of two non-mixing liquids A and B with its axis vertical. The densities of the liquids A and B are 0.7 g/cm3 and 1.2 g/cm3 respectively. The height of liquid A is hA=1.2 cm. The length of the part of the cylinder immersed in liquid B is hB=0.8 cm.
Answer» A uniform solid cylinder of density $0.8 g / {cm}^{3}$ floats in equilibrium in a combination of two non-mixing liquids A and B with its axis vertical. The densities of the liquids A and B are $0.7 g / {cm}^{3}$ and $1.2 g / {cm}^{3}$ respectively. The height of liquid A is $h_{A} = 1.2 cm$ . The length of the part of the cylinder immersed in liquid B is $h_{B} = 0.8 cm$ .

1957.

A uniform solid cylinder of density 0.8 g/cm3 floats in equilibrium in a combination of two non-mixing liquids A and B with its axis vertical. The densities of the liquids A and B are 0.7 g/cm3 and 1.2 g/cm3 respectively. The height of liquid A is hA=1.2 cm. The length of the part of the cylinder immersed in liquid B is hB=0.8 cm.

Answer»

A uniform solid cylinder of density $0.8 g / {cm}^{3}$ floats in equilibrium in a combination of two non-mixing liquids A and B with its axis vertical. The densities of the liquids A and B are $0.7 g / {cm}^{3}$ and $1.2 g / {cm}^{3}$ respectively. The height of liquid A is $h_{A} = 1.2 cm$ . The length of the part of the cylinder immersed in liquid B is $h_{B} = 0.8 cm$ .

Discussion

1958.	29.A metal sphere weighing 60gm in air is suspended by a thread in an oil of specfic gravity 0.6. If the tension in the thread is 55gmt the specfic gravity of the metal sphere is?
Answer» 29.A metal sphere weighing 60gm in air is suspended by a thread in an oil of specfic gravity 0.6. If the tension in the thread is 55gmt the specfic gravity of the metal sphere is?

Discussion

1959.	Nylon is made from coal, water and air which are obtained from nature. Then why it is called Synthetic Fibre?
Answer» Nylon is made from coal, water and air which are obtained from nature. Then why it is called Synthetic Fibre?

Discussion

1960.	Prepare a brief speech on global warming. You have to deliver the speech in your class.
Answer» Prepare a brief speech on global warming. You have to deliver the speech in your class.

Discussion

1961.	Which of the following is an example of exhaustible resources?
Answer» Which of the following is an example of exhaustible resources?

Discussion

1962.

Aqueous solutions of zinc sulphate and iron sulphate were taken in the test tubes I and II by four students. A, B, C and D. Metal pieces of iron and zinc were dropped in the two solutions and observations made after several hours and recorded in the form of a table as given below: Observation by Metal Solution Colour change of solution Deposit/Residue obtained A Fe ZnSO4 turned green silvery grey coating Zn FeSO4 no change no change B Fe ZnSO4 no change black residue Zn FeSO4 colour faded grey coating C Fe ZnSO4 no change no change Zn FeSO4 turned colourless black residue D Fe ZnSO4 no change grey residue Zn FeSO4 no change black residue The correct reporting has been made observations reported by the student :(1) A(2) B(3) C(4) D

Answer» Aqueous solutions of zinc sulphate and iron sulphate were taken in the test tubes I and II by four students. A, B, C and D. Metal pieces of iron and zinc were dropped in the two solutions and observations made after several hours and recorded in the form of a table as given below:

Observation by	Metal	Solution	Colour change of solution	Deposit/Residue obtained
A	Fe	ZnSO₄	turned green	silvery grey coating
A	Zn	FeSO₄	no change	no change
B	Fe	ZnSO₄	no change	black residue
B	Zn	FeSO₄	colour faded	grey coating
C	Fe	ZnSO₄	no change	no change
C	Zn	FeSO₄	turned colourless	black residue
D	Fe	ZnSO₄	no change	grey residue
D	Zn	FeSO₄	no change	black residue

The correct reporting has been made observations reported by the student :

(1) A

(2) B

(3) C

(4) D

Discussion

1963.	Which of the following is not a greenhouse gas?
Answer» Which of the following is not a greenhouse gas?

Discussion

1964.	How many molecules of O2 are present in 1L of air containing 80 percent of O2 at STP
Answer» How many molecules of O2 are present in 1L of air containing 80 percent of O2 at STP

Discussion

1965.	10. What is the effect of heat on the states of matter?Illustrate the effect of heat on ice.
Answer» 10. What is the effect of heat on the states of matter?Illustrate the effect of heat on ice.

Discussion

1966.	A physician wishes to prepare a buffersolution at pH = 3.58 that efficiently resists a change in pH yet contains onlysmall conc. of the buffering agents. Which one of the following weak acidtogether with its sodium salt would be best to use?
Answer» A physician wishes to prepare a buffer solution at pH = 3.58 that efficiently resists a change in pH yet contains only small conc. of the buffering agents. Which one of the following weak acid together with its sodium salt would be best to use?

Discussion

1967.	Calculate the molecular mass of the following: (i) H2O (ii) CO2 (iii) CH4
Answer» Calculate the molecular mass of the following: (i) H₂O (ii) CO₂ (iii) CH₄

1967.

Calculate the molecular mass of the following: (i) H2O (ii) CO2 (iii) CH4

Answer»

Calculate the molecular mass of the following:

(i) H₂O (ii) CO₂ (iii) CH₄

Discussion

1968.	find the electric field at center of a semicircular ring of radius R ; and having half (+)ve and half (-)ve charge.
Answer» find the electric field at center of a semicircular ring of radius R ; and having half (+)ve and half (-)ve charge.

Discussion

1969.	Are the terms bis tris tetrakis considered in alphabetical order for naming organic compounds ?
Answer» Are the terms bis tris tetrakis considered in alphabetical order for naming organic compounds ?

Discussion

1970.	What is green house effect
Answer» What is green house effect

Discussion

1971.	An astronaut makes water on the moon by mixing hydrogen and oxygen. Will the mass ratio of hydrogen to oxygen of the water that he made on the Moon will be same as that on the Earth?
Answer» An astronaut makes water on the moon by mixing hydrogen and oxygen. Will the mass ratio of hydrogen to oxygen of the water that he made on the Moon will be same as that on the Earth?

Discussion

1972.	Question 4 (d)Write the chemical formulae of the following:(d) Aluminium chloride
Answer» Question 4 (d) Write the chemical formulae of the following: (d) Aluminium chloride

Discussion

1973.	Give reasons.(a) Wateris not used to control fires involving electrical equipment.(b) LPG isa better domestic fuel than wood.(c) Paper by itself catches fire easily whereas a piece of paperwrapped around an aluminium pipe does not.
Answer» Give reasons. (a) Water is not used to control fires involving electrical equipment. (b) LPG is a better domestic fuel than wood. (c) Paper by itself catches fire easily whereas a piece of paper wrapped around an aluminium pipe does not.

1973.

Give reasons.(a) Wateris not used to control fires involving electrical equipment.(b) LPG isa better domestic fuel than wood.(c) Paper by itself catches fire easily whereas a piece of paperwrapped around an aluminium pipe does not.

Answer»

Give reasons.

(a) Water
is not used to control fires involving electrical equipment.

(b) LPG is
a better domestic fuel than wood.

(c) Paper by itself catches fire easily whereas a piece of paper
wrapped around an aluminium pipe does not.

Discussion

1974.	the rate of radioactive disintegration at an instant for a radioactive sample of half life 2.2*10^9 s is 10^10 .the no. of radioactive atoms in that sample at that instant is
Answer» the rate of radioactive disintegration at an instant for a radioactive sample of half life 2.2*10^9 s is 10^10 .the no. of radioactive atoms in that sample at that instant is

Discussion

1975.	what is acid anhydride
Answer» what is acid anhydride

Discussion

1976.	What is the maximum number of electrons that can be present in M-shell?
Answer» What is the maximum number of electrons that can be present in M-shell?

Discussion

1977.	If the concentration of OH- ions in the reaction Fe(OH)3 gives Fe3+ + 3OHDecreased by 1/4 the equilibrium concentration of Fe3+ will increase by ?
Answer» If the concentration of OH- ions in the reaction Fe(OH)3 gives Fe3+ + 3OH Decreased by 1/4 the equilibrium concentration of Fe3+ will increase by ?

Discussion

1978.	What is atomic radii
Answer» What is atomic radii

Discussion

1979.	Question 2On the basis of Rutherford’s model of an atom, which subatomic particle is present in the nucleus of an atom?
Answer» Question 2 On the basis of Rutherford’s model of an atom, which subatomic particle is present in the nucleus of an atom?

Discussion

1980.	Elements are mostly grouped into metals, non-metals and___ .
Answer» Elements are mostly grouped into metals, non-metals and___ .

Discussion

1981.	3Fe+4H2O→Fe3O4+yH2 The value of y in the equation is ___
Answer» $3 F e + 4 H_{2} O \to F e_{3} O_{4} + y H_{2}$ The value of y in the equation is ___

Discussion

1982.	Why does gravitational force not depend upon the medium between the two bodies?
Answer» Why does gravitational force not depend upon the medium between the two bodies?

Discussion

1983.	Question 1 (f)Classify the following as chemical or physical changes: f. Dissolving common salt in water
Answer» Question 1 (f) Classify the following as chemical or physical changes: f. Dissolving common salt in water

Discussion

1984.	What is rust and mention the necessary conditions for rusting?
Answer» What is rust and mention the necessary conditions for rusting?

Discussion

1985.	Why do HCl, HNO3, etc., show acidic characters in aqueous solutions while solutions of compounds like alcohol and glucose do not show acidic character?
Answer» Why do HCl, $H N O_{3}$ , etc., show acidic characters in aqueous solutions while solutions of compounds like alcohol and glucose do not show acidic character?

Discussion

1986.	Which element is considered as the most versatile atom on Earth?
Answer» Which element is considered as the most versatile atom on Earth?

Discussion

1987.	Question 3 (f)Discuss the effects of deforestation on the next generation.
Answer» Question 3 (f) Discuss the effects of deforestation on the next generation.

Discussion

1988.	What is the water of crystallization of blue vitriol?5
Answer» What is the water of crystallization of blue vitriol? 5

Discussion

1989.	ntif we consider that 1/6, in place of 1/12,mass of carbon atom is taken to be relative atomic mass unit ,the mass of 1 mole of substance will?n
Answer» ntif we consider that 1/6, in place of 1/12,mass of carbon atom is taken to be relative atomic mass unit ,the mass of 1 mole of substance will?n

Discussion

1990.	What is empirical formula of a compound containing 50.1% sulphur and 49.9% oxygen by Mass?
Answer» What is empirical formula of a compound containing 50.1% sulphur and 49.9% oxygen by Mass?

Discussion

1991.	Metals can be converted into sheets by hammering. This property of metals is called
Answer» Metals can be converted into sheets by hammering. This property of metals is called

Discussion

1992.	An hypothetical element (Y) has two oxides if first oxide (YO) contain 40% oxygen and second oxide contain 20% oxygen then the formula of second oxide isoptions YO2 Y8O3 Y20 Y2O5 EXPLAIN HOW Y8O3 ??
Answer» An hypothetical element (Y) has two oxides if first oxide (YO) contain 40% oxygen and second oxide contain 20% oxygen then the formula of second oxide is options YO2 Y8O3 Y20 Y2O5 EXPLAIN HOW Y8O3 ??

Discussion

1993.	What measure has been taken in Delhi to fight against air pollution?
Answer» What measure has been taken in Delhi to fight against air pollution?

Discussion

1994.	Simple definition of equivalent cconductivity and molar conductivity .
Answer» Simple definition of equivalent cconductivity and molar conductivity .

Discussion

1995.	'Manufacturing synthetic fibres is actually helping conservation of forests'. Comment.
Answer» 'Manufacturing synthetic fibres is actually helping conservation of forests'. Comment.

Discussion

1996.	Rean bought a statue made of copper. To her surprise it acquired a dull green coating after a couple of months. in the explain the reason
Answer» Rean bought a statue made of copper. To her surprise it acquired a dull green coating after a couple of months. in the explain the reason

Discussion

1997.	What is difference between true solution and suspension and colloid?
Answer» What is difference between true solution and suspension and colloid?

Discussion

1998.	Nylon is ___ .
Answer» Nylon is ___ .

Discussion

1999.	(a) Name the chemicals required for the preparation of carbon dioxide in the laboratory. (b) How will you collect the gas? (c) Write the balanced chemical equation for the above reaction. (d) Why is sulphuric acid not used for the preparation of carbon dioxide in the laboratory?
Answer» (a) Name the chemicals required for the preparation of carbon dioxide in the laboratory. (b) How will you collect the gas? (c) Write the balanced chemical equation for the above reaction. (d) Why is sulphuric acid not used for the preparation of carbon dioxide in the laboratory?

1999.

(a) Name the chemicals required for the preparation of carbon dioxide in the laboratory. (b) How will you collect the gas? (c) Write the balanced chemical equation for the above reaction. (d) Why is sulphuric acid not used for the preparation of carbon dioxide in the laboratory?

Answer»

(a) Name the chemicals required for the preparation of carbon dioxide in the laboratory.

(b) How will you collect the gas?

(c) Write the balanced chemical equation for the above reaction.

(d) Why is sulphuric acid not used for the preparation of carbon dioxide in the laboratory?

Discussion

2000.	What is meant by boiling point and freezing point? Write the boiling point and freezing point of water.
Answer» What is meant by boiling point and freezing point? Write the boiling point and freezing point of water.

Discussion

Explore topic-wise InterviewSolutions in .

What is the process of obtaining crystals of a substance from its solution in water called?

As seen in the figure, two nails are carefully dipped in copper sulphate solution with the help of threads. What will happen when the nails are removed after half an hour?

How do we clean silver or brass articles that have got tarnished?

Question 7.What kind of change is burning of a candle?

Why is chromium plating done on many objects such as car parts, bath taps etc.? Why is steel not preferred as a car part or a bath tap?

It is advised not to throw plastic in garbage dumping area as:

29.A metal sphere weighing 60gm in air is suspended by a thread in an oil of specfic gravity 0.6. If the tension in the thread is 55gmt the specfic gravity of the metal sphere is?

Nylon is made from coal, water and air which are obtained from nature. Then why it is called Synthetic Fibre?

Prepare a brief speech on global warming. You have to deliver the speech in your class.​

Which of the following is an example of exhaustible resources?

Which of the following is not a greenhouse gas?

How many molecules of O2 are present in 1L of air containing 80 percent of O2 at STP

10. What is the effect of heat on the states of matter?Illustrate the effect of heat on ice.

A physician wishes to prepare a buffersolution at pH = 3.58 that efficiently resists a change in pH yet contains onlysmall conc. of the buffering agents. Which one of the following weak acidtogether with its sodium salt would be best to use?

Calculate the molecular mass of the following: (i) H2O (ii) CO2 (iii) CH4

find the electric field at center of a semicircular ring of radius R ; and having half (+)ve and half (-)ve charge.

Are the terms bis tris tetrakis considered in alphabetical order for naming organic compounds ?

What is green house effect

An astronaut makes water on the moon by mixing hydrogen and oxygen. Will the mass ratio of hydrogen to oxygen of the water that he made on the Moon will be same as that on the Earth?

Question 4 (d)Write the chemical formulae of the following:(d) Aluminium chloride

Give reasons.(a) Wateris not used to control fires involving electrical equipment.(b) LPG isa better domestic fuel than wood.(c) Paper by itself catches fire easily whereas a piece of paperwrapped around an aluminium pipe does not.

the rate of radioactive disintegration at an instant for a radioactive sample of half life 2.2*10^9 s is 10^10 .the no. of radioactive atoms in that sample at that instant is

what is acid anhydride

What is the maximum number of electrons that can be present in M-shell?

If the concentration of OH- ions in the reaction Fe(OH)3 gives Fe3+ + 3OHDecreased by 1/4 the equilibrium concentration of Fe3+ will increase by ?

What is atomic radii

Question 2On the basis of Rutherford’s model of an atom, which subatomic particle is present in the nucleus of an atom?

Elements are mostly grouped into metals, non-metals and___ .

3Fe+4H2O→Fe3O4+yH2 The value of y in the equation is ___

Why does gravitational force not depend upon the medium between the two bodies?

Question 1 (f)Classify the following as chemical or physical changes: f. Dissolving common salt in water

What is rust and mention the necessary conditions for rusting?

Why do HCl, HNO3, etc., show acidic characters in aqueous solutions while solutions of compounds like alcohol and glucose do not show acidic character?

Which element is considered as the most versatile atom on Earth?

Question 3 (f)Discuss the effects of deforestation on the next generation.

What is the water of crystallization of blue vitriol?5

ntif we consider that 1/6, in place of 1/12,mass of carbon atom is taken to be relative atomic mass unit ,the mass of 1 mole of substance will?n

What is empirical formula of a compound containing 50.1% sulphur and 49.9% oxygen by Mass?

Metals can be converted into sheets by hammering. This property of metals is called

An hypothetical element (Y) has two oxides if first oxide (YO) contain 40% oxygen and second oxide contain 20% oxygen then the formula of second oxide isoptions YO2 Y8O3 Y20 Y2O5 EXPLAIN HOW Y8O3 ??

What measure has been taken in Delhi to fight against air pollution?

Simple definition of equivalent cconductivity and molar conductivity .

'Manufacturing synthetic fibres is actually helping conservation of forests'. Comment.

Rean bought a statue made of copper. To her surprise it acquired a dull green coating after a couple of months. in the explain the reason

What is difference between true solution and suspension and colloid?

Nylon is ___ .

(a) Name the chemicals required for the preparation of carbon dioxide in the laboratory. (b) How will you collect the gas? (c) Write the balanced chemical equation for the above reaction. (d) Why is sulphuric acid not used for the preparation of carbon dioxide in the laboratory?

What is meant by boiling point and freezing point? Write the boiling point and freezing point of water.

Prepare a brief speech on global warming. You have to deliver the speech in your class.