5083 + Interview Questions in Chemistry Page 5 InterviewSolution

201.	How many molecules and atoms are present in 5O2?
Answer» How many molecules and atoms are present in $5 O_{2}$ ?

Discussion

202.	Differtate between chemical and physical change
Answer» Differtate between chemical and physical change

Discussion

203.	What is difference between atomicity and valency?
Answer» What is difference between atomicity and valency?

Discussion

204.	What kind of soil will hold more water–one made up of small particles or one with bigger particles?
Answer» What kind of soil will hold more water–one made up of small particles or one with bigger particles?

Discussion

205.	Anu showed Appu a sample of water from the Ganga River. It was not transparent and contained some suspended grime. Appu said that he could make it drinkable. He filtered the water using a filter paper to remove the grime. The filtered water was clean; Appu also boiled this water to kill harmful microbes and gave it to Anu to drink. Anu said that the water was still polluted and undrinkable. Can you say why?
Answer» Anu showed Appu a sample of water from the Ganga River. It was not transparent and contained some suspended grime. Appu said that he could make it drinkable. He filtered the water using a filter paper to remove the grime. The filtered water was clean; Appu also boiled this water to kill harmful microbes and gave it to Anu to drink. Anu said that the water was still polluted and undrinkable. Can you say why?

Discussion

206.	Draw the graph of disintegrated mass of radioactive nuclei versus time
Answer» Draw the graph of disintegrated mass of radioactive nuclei versus time

Discussion

207.	2NH3 → N2+3H2 Write down the rate expression for the above reaction.
Answer» $2 N H_{3}$ $\to$ $N_{2} + 3 H_{2}$ Write down the rate expression for the above reaction.

207.

2NH3 → N2+3H2 Write down the rate expression for the above reaction.

Answer»

$2 N H_{3}$ $\to$ $N_{2} + 3 H_{2}$

Write down the rate expression for the above reaction.

Discussion

208.	Which amongst the following is true about electrolytes?
Answer» Which amongst the following is true about electrolytes?

Discussion

209.	What was the main occupation of Gond people?
Answer» What was the main occupation of Gond people?

Discussion

210.	Identify the physical state of matter which can be easily compressed.
Answer» Identify the physical state of matter which can be easily compressed.

Discussion

211.	Sodium chloride and sand are mixed in water. The resultant mixture is heated for a long time. What will we find at the end?
Answer» Sodium chloride and sand are mixed in water. The resultant mixture is heated for a long time. What will we find at the end?

Discussion

212.	What is the difference between homogeneous and heterogeneous mixtures?
Answer» What is the difference between homogeneous and heterogeneous mixtures?

Discussion

213.	A student has been collecting silver coins and copper coins. One day she observed a black coating on silver coins and a green coating on copper coins. Which chemical phenomenon is responsible for these coatings? Write the chemical name of black and green coatings.
Answer» A student has been collecting silver coins and copper coins. One day she observed a black coating on silver coins and a green coating on copper coins. Which chemical phenomenon is responsible for these coatings? Write the chemical name of black and green coatings.

Discussion

214.	What will happen if a drop of phenolphthalein is added to an acid
Answer» What will happen if a drop of phenolphthalein is added to an acid

Discussion

215.	How does a cube of ice transform itself into liquid water?
Answer» How does a cube of ice transform itself into liquid water?

Discussion

216.	rate of reaction and tate of change of conentration a reac†an t are two different terms, tgen what the point of defining rate of reaction such strange way, why cant we take change concentrationof reac†an t per unit time as rae of reaction
Answer» rate of reaction and tate of change of conentration a reac†an t are two different terms, tgen what the point of defining rate of reaction such strange way, why cant we take change concentrationof reac†an t per unit time as rae of reaction

Discussion

217.	When a sample of soil is mixed in beaker with some water, a layer of the soil always floats on top. This layer is called humus. What is it composed of ?
Answer» When a sample of soil is mixed in beaker with some water, a layer of the soil always floats on top. This layer is called humus. What is it composed of ?

Discussion

218.	Difference between physical change and chemical change with example
Answer» Difference between physical change and chemical change with example

Discussion

219.	Usually, atoms combine together to form a ___
Answer» Usually, atoms combine together to form a ___

Discussion

220.	Which of the following statements is/are incorrect?
Answer» Which of the following statements is/are incorrect?

Discussion

221.	The ionic-end of soap dissolves in ___ while the carbon chain dissolves in ___.
Answer» The ionic-end of soap dissolves in ___ while the carbon chain dissolves in ___.

Discussion

222.	Discuss why wearing more layers of clothing during winter keeps us warmer than wearing just one thick piece of clothing.
Answer» Discuss why wearing more layers of clothing during winter keeps us warmer than wearing just one thick piece of clothing.

Discussion

223.	Hydrogen combines with oxygen to form two compounds namely water and hydrogen peroxide. In this reaction the masses of oxygen which combine with a fixed mass of hydrogen bear a simple ratio. The given statement can be explained on the basis of:
Answer» Hydrogen combines with oxygen to form two compounds namely water and hydrogen peroxide. In this reaction the masses of oxygen which combine with a fixed mass of hydrogen bear a simple ratio. The given statement can be explained on the basis of:

Discussion

224.	Which of the following is a good conductor of electricity?
Answer» Which of the following is a good conductor of electricity?

Discussion

225.	How to find basicity or acidity of a substance to find its equivalent weight?
Answer» How to find basicity or acidity of a substance to find its equivalent weight?

Discussion

226.	Which of the following is a metal displacement reaction ?
Answer» Which of the following is a metal displacement reaction ?

Discussion

227.	Question 2 Name the change in which the original identity of the substance can be retained. Give examples for the change mentioned in (a). Reversible changes are sometimes known as _____ (permanent change / temporary change).
Answer» Question 2 Name the change in which the original identity of the substance can be retained. Give examples for the change mentioned in (a). Reversible changes are sometimes known as _____ (permanent change / temporary change).

227.

Question 2 Name the change in which the original identity of the substance can be retained. Give examples for the change mentioned in (a). Reversible changes are sometimes known as _____ (permanent change / temporary change).

Answer»

Question 2

Name the change in which the original identity of the substance can be retained.

Give examples for the change mentioned in (a).

Reversible changes are sometimes known as _____ (permanent change / temporary change).

Discussion

228.	The usage of water is determined by ascertaining the quality of water. What are the factors that affect the quality of water? Why is the water table going down? [3 MARKS]
Answer» The usage of water is determined by ascertaining the quality of water. What are the factors that affect the quality of water? Why is the water table going down? [3 MARKS]

Discussion

229.	35. If the heat changw at constant volume for decomposition of silver oxide is 80.25kj. What will be the heat change at constant pressure
Answer» 35. If the heat changw at constant volume for decomposition of silver oxide is 80.25kj. What will be the heat change at constant pressure

Discussion

230.	Which of the following is not a mixture?
Answer» Which of the following is not a mixture?

Discussion

231.	Sodium chloride salt is used for cooking. It is formed when hydrochloric acid is added to sodium hydroxide solution, both of which are corrosive in nature. But sodium chloride is not. Give reasons.
Answer» Sodium chloride salt is used for cooking. It is formed when hydrochloric acid is added to sodium hydroxide solution, both of which are corrosive in nature. But sodium chloride is not. Give reasons.

Discussion

232.	The resistance of a 0.02 N solution of an electrolyte MgCl2 was found to be 210 ohm at 298 K using a conductivity cell with a cell constant of 0.88 cm−1. Calculate the equivalent conductivity of the solution.
Answer» The resistance of a $0.02 N$ solution of an electrolyte $M g C l_{2}$ was found to be $210 o h m$ at $298 K$ using a conductivity cell with a cell constant of $0.88 c m^{- 1}$ . Calculate the equivalent conductivity of the solution.

Discussion

233.	Match the correct option
Answer» Match the correct option

233.

Match the correct option

Answer»

Match the correct option

Discussion

234.	Half-life period of a first-order reaction is 10 minutes. Starting with 10 mol L−1, rate after 20 minutes will be :
Answer» Half-life period of a first-order reaction is $10$ minutes. Starting with $10$ ${mol L}^{- 1}$ , rate after $20$ minutes will be :

Discussion

235.	A real gas obeying van der Waals equation will resemble an ideal gas if the:
Answer» A real gas obeying van der Waals equation will resemble an ideal gas if the:

Discussion

236.	Brief Note on Psuedo Noble Gas Configuration: All Elements which show P.N.G.C Electronic Configuration of P.N.G.C
Answer» Brief Note on Psuedo Noble Gas Configuration: All Elements which show P.N.G.C Electronic Configuration of P.N.G.C

Discussion

237.	10.A potential difference of V volt is applied across the faces of a germanium crystal plate. The face area of the crystal is A and its thickness is l. The free electron concentration in germanium is n and the electron and holes mobilities are a and b respectively. Then prove that current across the plate will be i = [eAVn(a+b)]/l
Answer» 10.A potential difference of V volt is applied across the faces of a germanium crystal plate. The face area of the crystal is A and its thickness is l. The free electron concentration in germanium is n and the electron and holes mobilities are a and b respectively. Then prove that current across the plate will be i = [eAVn(a+b)]/l

Discussion

238.	What is the speed of the veins in our body to send messages to brain?
Answer» What is the speed of the veins in our body to send messages to brain?

Discussion

239.	“Forests are our lifeline.” Write five sentences on this topic.
Answer» “Forests are our lifeline.” Write five sentences on this topic.

Discussion

240.	Which of the following mixtures can be separated into its constituents using centrifugation?
Answer» Which of the following mixtures can be separated into its constituents using centrifugation?

Discussion

241.	Question 1Lustre is the shine of a material. (a) What are Lustrous objects? Give examples(b) What are non-lustrous objects? Give examples(c) Name a non-metal that is lustrous in nature (HINT: it is the hardest known material).
Answer» Question 1 Lustre is the shine of a material. (a) What are Lustrous objects? Give examples (b) What are non-lustrous objects? Give examples (c) Name a non-metal that is lustrous in nature (HINT: it is the hardest known material).

241.

Question 1Lustre is the shine of a material. (a) What are Lustrous objects? Give examples(b) What are non-lustrous objects? Give examples(c) Name a non-metal that is lustrous in nature (HINT: it is the hardest known material).

Answer»

Question 1

Lustre is the shine of a material.

(a) What are Lustrous objects? Give examples

(b) What are non-lustrous objects? Give examples

(c) Name a non-metal that is lustrous in nature (HINT: it is the hardest known material).

Discussion

242.	Choose the incorrect statement(s) about physical change:-
Answer» Choose the incorrect statement(s) about physical change:-

Discussion

243.	An electric current of 100 ampere is passed through a molten liquid of sodium chloride between platinum electrodes for 5 hours. Calculate the volume of chlorine gas liberated at the electrode at NTP.[Molar mass of Cl2 is 71 g/mol]
Answer» An electric current of $100$ ampere is passed through a molten liquid of sodium chloride between platinum electrodes for 5 hours. Calculate the volume of chlorine gas liberated at the electrode at NTP. [Molar mass of $C l_{2}$ is $71 g / m o l$ ]

Discussion

244.	Que. 25 ml of a solution containing NaOH and Na2CO3 required 1)50 ml of 0.2 N HCI using phenolphthalein as indicator 2) 72 ml of 0.2N HCI when titrated using methyl orange as indicator. The ratio of weight of NaOH and Na2CO3, in this solution is (1)0.48 (2) 0.44 (3) 0.40 (4) 0.38
Answer» Que. 25 ml of a solution containing NaOH and Na2CO3 required 1)50 ml of 0.2 N HCI using phenolphthalein as indicator 2) 72 ml of 0.2N HCI when titrated using methyl orange as indicator. The ratio of weight of NaOH and Na2CO3, in this solution is (1)0.48 (2) 0.44 (3) 0.40 (4) 0.38

Discussion

245.	0.5g of Ba-hydroxide , 0.01 mol Ba-hydroxide and 0.01eq Ba-hydroxide were together diluted to one litre. Calculate the normality of the basic solution.
Answer» 0.5g of Ba-hydroxide , 0.01 mol Ba-hydroxide and 0.01eq Ba-hydroxide were together diluted to one litre. Calculate the normality of the basic solution.

Discussion

246.	18. Find Out mole fraction of solvent in 3 molal aqueous solution
Answer» 18. Find Out mole fraction of solvent in 3 molal aqueous solution

Discussion

247.	Why boron and carbon are exceptions!
Answer» Why boron and carbon are exceptions!

Discussion

248.	An acid base indicator has Ka of 3×10−5. The acid form of the indicator is red and the basic form is blue. By how much must the pH change in order to change the indicator from 75% red to 75% blue?
Answer» An acid base indicator has $K_{a}$ of $3 \times 10^{- 5}$ . The acid form of the indicator is red and the basic form is blue. By how much must the $p H$ change in order to change the indicator from $75 %$ red to $75 %$ blue?

Discussion

249.	When a student added red litmus to an aqueous solution, the red litmus turned blue. Which one of the following should be added in excess so that the change in colour is reversed?(1) baking soda solution(2) lime water (3) vinegar solution(4) ammonia solution
Answer» When a student added red litmus to an aqueous solution, the red litmus turned blue. Which one of the following should be added in excess so that the change in colour is reversed? (1) baking soda solution (2) lime water (3) vinegar solution (4) ammonia solution

Discussion

250.	why didn't carbon join in front of the two oxygen atoms,why only in between the two oxygen atoms?
Answer» why didn't carbon join in front of the two oxygen atoms,why only in between the two oxygen atoms?

Discussion

Explore topic-wise InterviewSolutions in .

How many molecules and atoms are present in 5O2?

Differtate between chemical and physical change

What is difference between atomicity and valency?

What kind of soil will hold more water–one made up of small particles or one with bigger particles?

Draw the graph of disintegrated mass of radioactive nuclei versus time

2NH3 → N2+3H2 Write down the rate expression for the above reaction.

Which amongst the following is true about electrolytes?

What was the main occupation of Gond people?

Identify the physical state of matter which can be easily compressed.

Sodium chloride and sand are mixed in water. The resultant mixture is heated for a long time. What will we find at the end?

What is the difference between homogeneous and heterogeneous mixtures?

A student has been collecting silver coins and copper coins. One day she observed a black coating on silver coins and a green coating on copper coins. Which chemical phenomenon is responsible for these coatings? Write the chemical name of black and green coatings.

What will happen if a drop of phenolphthalein is added to an acid

How does a cube of ice transform itself into liquid water?

rate of reaction and tate of change of conentration a reac†an t are two different terms, tgen what the point of defining rate of reaction such strange way, why cant we take change concentrationof reac†an t per unit time as rae of reaction

When a sample of soil is mixed in beaker with some water, a layer of the soil always floats on top. This layer is called humus. What is it composed of ?

Difference between physical change and chemical change with example

Usually, atoms combine together to form a ___

Which of the following statements is/are incorrect?

The ionic-end of soap dissolves in ___ while the carbon chain dissolves in ___.

Discuss why wearing more layers of clothing during winter keeps us warmer than wearing just one thick piece of clothing.

Hydrogen combines with oxygen to form two compounds namely water and hydrogen peroxide. In this reaction the masses of oxygen which combine with a fixed mass of hydrogen bear a simple ratio. The given statement can be explained on the basis of:

Which of the following is a good conductor of electricity?

How to find basicity or acidity of a substance to find its equivalent weight?

Which of the following is a metal displacement reaction ?

Question 2 Name the change in which the original identity of the substance can be retained. Give examples for the change mentioned in (a). Reversible changes are sometimes known as _____ (permanent change / temporary change).

The usage of water is determined by ascertaining the quality of water. What are the factors that affect the quality of water? Why is the water table going down? [3 MARKS]

35. If the heat changw at constant volume for decomposition of silver oxide is 80.25kj. What will be the heat change at constant pressure

Which of the following is not a mixture?

Sodium chloride salt is used for cooking. It is formed when hydrochloric acid is added to sodium hydroxide solution, both of which are corrosive in nature. But sodium chloride is not. Give reasons.

The resistance of a 0.02 N solution of an electrolyte MgCl2 was found to be 210 ohm at 298 K using a conductivity cell with a cell constant of 0.88 cm−1. Calculate the equivalent conductivity of the solution.

Match the correct option

Half-life period of a first-order reaction is 10 minutes. Starting with 10 mol L−1, rate after 20 minutes will be :

A real gas obeying van der Waals equation will resemble an ideal gas if the:

Brief Note on Psuedo Noble Gas Configuration: All Elements which show P.N.G.C Electronic Configuration of P.N.G.C

What is the speed of the veins in our body to send messages to brain?

“Forests are our lifeline.” Write five sentences on this topic.

Which of the following mixtures can be separated into its constituents using centrifugation?

Question 1Lustre is the shine of a material. (a) What are Lustrous objects? Give examples(b) What are non-lustrous objects? Give examples(c) Name a non-metal that is lustrous in nature (HINT: it is the hardest known material).

Choose the incorrect statement(s) about physical change:-

An electric current of 100 ampere is passed through a molten liquid of sodium chloride between platinum electrodes for 5 hours. Calculate the volume of chlorine gas liberated at the electrode at NTP.[Molar mass of Cl2 is 71 g/mol]

Que. 25 ml of a solution containing NaOH and Na2CO3 required 1)50 ml of 0.2 N HCI using phenolphthalein as indicator 2) 72 ml of 0.2N HCI when titrated using methyl orange as indicator. The ratio of weight of NaOH and Na2CO3, in this solution is (1)0.48 (2) 0.44 (3) 0.40 (4) 0.38

0.5g of Ba-hydroxide , 0.01 mol Ba-hydroxide and 0.01eq Ba-hydroxide were together diluted to one litre. Calculate the normality of the basic solution.

18. Find Out mole fraction of solvent in 3 molal aqueous solution

Why boron and carbon are exceptions!

An acid base indicator has Ka of 3×10−5. The acid form of the indicator is red and the basic form is blue. By how much must the pH change in order to change the indicator from 75% red to 75% blue?

When a student added red litmus to an aqueous solution, the red litmus turned blue. Which one of the following should be added in excess so that the change in colour is reversed?(1) baking soda solution(2) lime water (3) vinegar solution(4) ammonia solution

why didn't carbon join in front of the two oxygen atoms,why only in between the two oxygen atoms?

The ionic-end of soap dissolves in _ while the carbon chain dissolves in _.