15280 + Interview Questions in Chemistry Page 18 InterviewSolution

851.	(a) Why are alkali metals kept in kerosene oil? (b) What is : (i) basic lead carbonate and (ii) brown powder deposit on iron? (c) Why is hydrogen kept in the metal activity series?
Answer» (a) Why are alkali metals kept in kerosene oil? (b) What is : (i) basic lead carbonate and (ii) brown powder deposit on iron? (c) Why is hydrogen kept in the metal activity series?

851.

(a) Why are alkali metals kept in kerosene oil? (b) What is : (i) basic lead carbonate and (ii) brown powder deposit on iron? (c) Why is hydrogen kept in the metal activity series?

Answer»

(a) Why are alkali metals kept in kerosene oil?

(b) What is :

(i) basic lead carbonate and

(ii) brown powder deposit on iron?

(c) Why is hydrogen kept in the metal activity series?

Discussion

852.	Which group of elements is stored in oil due to their reactive nature with water and air?
Answer» Which group of elements is stored in oil due to their reactive nature with water and air?

Discussion

853.	Oxidising Agent + Hydrochloric Acid → Salt + Water + ___
Answer» Oxidising Agent + Hydrochloric Acid → Salt + Water + ___

Discussion

854.	An element, X has the following isotopiccomposition 200X : 90% 199X: 8% 202X : 2.0%. Theweighted average atomic mass of the naturallyoccurring element X is closest to(2) 202 amu(1) 201 amu(4) 200 amu(3) 199 amu
Answer» An element, X has the following isotopiccomposition 200X : 90% 199X: 8% 202X : 2.0%. Theweighted average atomic mass of the naturallyoccurring element X is closest to(2) 202 amu(1) 201 amu(4) 200 amu(3) 199 amu

Discussion

855.	how many grams of Naoh are present in 250ml of 0.5M naoh solution ?
Answer» how many grams of Naoh are present in 250ml of 0.5M naoh solution ?

Discussion

856.	If x molecules of CH4 are removed from 44.8L of methane sample, then it was observed that 10 g of CH4 was remained . find the value of x.
Answer» If x molecules of CH4 are removed from 44.8L of methane sample, then it was observed that 10 g of CH4 was remained . find the value of x.

Discussion

857.	The IP1, IP2, IP3, IP4 and IP5 of an element are 7.1, 14.3, 34.5, 46.8, 162.2 eV respectively. The element is likely to be -
Answer» The IP1, IP2, IP3, IP4 and IP5 of an element are 7.1, 14.3, 34.5, 46.8, 162.2 eV respectively. The element is likely to be -

Discussion

858.	If 25ml of a sulphuric acid solution reacts completely with 1.06 g of pure sodium carbonate, what is the normality of this acid solution?
Answer» If 25ml of a sulphuric acid solution reacts completely with 1.06 g of pure sodium carbonate, what is the normality of this acid solution?

Discussion

859.	State a safety precaution taken during the preparation of hydrochloric acid through funnel experiment.
Answer» State a safety precaution taken during the preparation of hydrochloric acid through funnel experiment.

Discussion

860.	27. What are rigid and elastic diatomic molecules?
Answer» 27. What are rigid and elastic diatomic molecules?

Discussion

861.

The substituents R1 and R2 for nine peptides are listed in the table given below. How many of these peptides are positively charged at pH=7.0? Peptide R1 R2 I H H II H CH3 III −CH2COOH H IV −CH2CONH2 (CH2)4NH2 V −CH2CONH2 −CH2CONH2 VI (CH2)4NH2 (CH2)4NH2 VII −CH2COOH −CH2CONH2 VIII −CH2OH (CH2)4NH2 IX (CH2)4NH2 CH3

Answer» The substituents

R_{1}

and

R_{2}

for nine peptides are listed in the table given below. How many of these peptides are positively charged at pH=7.0?

Peptide	$R_{1}$	$R_{2}$
I	H	H
II	H	$C H_{3}$
III	$- C H_{2} C O O H$	H
IV	$- C H_{2} C O N H_{2}$	$(C H_{2})_{4} N H_{2}$
V	$- C H_{2} C O N H_{2}$	$- C H_{2} C O N H_{2}$
VI	$(C H_{2})_{4} N H_{2}$	$(C H_{2})_{4} N H_{2}$
VII	$- C H_{2} C O O H$	$- C H_{2} C O N H_{2}$
VIII	$- C H_{2} O H$	$(C H_{2})_{4} N H_{2}$
IX	$(C H_{2})_{4} N H_{2}$	$C H_{3}$

Discussion

862.	When a glass rod dipped in ammonia solution is brought near vapours of hydrochloric acid we see the formation of a dense white fume. What is this dense white fume?
Answer» When a glass rod dipped in ammonia solution is brought near vapours of hydrochloric acid we see the formation of a dense white fume. What is this dense white fume?

Discussion

863.	when 1-chloro-2,2-dimethyl propane is treated with NaOH /DMSO then reaction does not occur but when treated with aqueous NaOH then it give Sn1 reaction .why??
Answer» when 1-chloro-2,2-dimethyl propane is treated with NaOH /DMSO then reaction does not occur but when treated with aqueous NaOH then it give Sn1 reaction .why??

Discussion

864.	What are ions and molecules and compounds.
Answer» ^{_{What are ions and molecules and compounds.}}

Discussion

865.	The property which is common between vinegar and curd is that they:
Answer» The property which is common between vinegar and curd is that they:

Discussion

866.	MnO2,PbO2 and red lead react with conc. HCl acid liberates Cl2. What is the common property being shown by these metal oxides ?
Answer» $M n O_{2}, P b O_{2}$ and red lead react with conc. HCl acid liberates $C l_{2}$ . What is the common property being shown by these metal oxides ?

Discussion

867.	Explain the reactivity series of metals and arrange the given metals in the descending order of their reactivity. Aluminium, Copper, Potassium
Answer» Explain the reactivity series of metals and arrange the given metals in the descending order of their reactivity. Aluminium, Copper, Potassium

Discussion

868.	The standard potential of the reaction H2O + e- gives 1/2 H2 + OH- at 298 K by using Kw(H2O) = 10 raise to the power -14 , is___
Answer» The standard potential of the reaction H2O + e- gives 1/2 H2 + OH- at 298 K by using Kw(H2O) = 10 raise to the power -14 , is___

Discussion

869.	In any ionic crystal A has formed cubical closepacking and B atoms are present at everytetrahedral voids. If any sample of crystal containN' number of B atoms then number of A atoms inthat sample is
Answer» In any ionic crystal A has formed cubical closepacking and B atoms are present at everytetrahedral voids. If any sample of crystal containN' number of B atoms then number of A atoms inthat sample is

Discussion

870.	2CO2 (g)+2H2(g)→2CO(g)+ 2H2O(g) In this reaction ______ is getting oxidised.
Answer» $2 {CO}_{2} (g) + 2 H_{2} (g) \to 2 CO (g) + 2 H_{2} O (g)$ In this reaction ______ is getting oxidised.

Discussion

871.	How to find the charge of an ionic compound
Answer» How to find the charge of an ionic compound

Discussion

872.	The ‘green rust’ of copper is scrapped and dissolved in water. When litmus paper is dipped in it, what will be the change in colour ?
Answer» The ‘green rust’ of copper is scrapped and dissolved in water. When litmus paper is dipped in it, what will be the change in colour ?

Discussion

873.	Which of the following sets of quantum numbers represents the highest energy for an atom?
Answer» Which of the following sets of quantum numbers represents the highest energy for an atom?

Discussion

874.	How many elements were known at the time of Mendeleev?
Answer» How many elements were known at the time of Mendeleev?

Discussion

875.	Write a note on the position of metals and non-metals in the periodic table.
Answer» Write a note on the position of metals and non-metals in the periodic table.

Discussion

876.	What would you observe in the following case:Ammonium hydroxide is first added in a small quantity and then in excess to a solution of copper sulphate.
Answer» What would you observe in the following case: Ammonium hydroxide is first added in a small quantity and then in excess to a solution of copper sulphate.

Discussion

877.	38. What is the highest occupied molecular orbital in NO+ ?
Answer» 38. What is the highest occupied molecular orbital in NO+ ?

Discussion

878.	Why is it not possible to remove stains with water alone?
Answer» Why is it not possible to remove stains with water alone?

Discussion

879.	What is the basis of behaviour as strong or weak field ligands for NH3 and H2O
Answer» What is the basis of behaviour as strong or weak field ligands for NH3 and H2O

Discussion

880.	Question 5 (a)State the following statement is True or False:Fossil fuels can be made in the laboratory.
Answer» Question 5 (a) State the following statement is True or False: Fossil fuels can be made in the laboratory.

Discussion

881.	What is an oxidation reaction ? Identify in the following reactions : (i) the substance oxidised (ii) the substance reduced. ZnO+C→Zn+CO
Answer» What is an oxidation reaction ? Identify in the following reactions : (i) the substance oxidised (ii) the substance reduced. $Z n O + C \to Z n + C O$

Discussion

882.	Which of the following options correctly represents the bond formed between hydrogen and chlorine in HCl?
Answer» Which of the following options correctly represents the bond formed between hydrogen and chlorine in $H C l$ ?

Discussion

883.	why benzene is more stable?
Answer» why benzene is more stable?

Discussion

884.	The element Z=114 has been discovered recently. It will belong to which of the following group:(a) Halogen family.(b) Carbon family.(c) Oxygen family.(d) Nitrogen family.
Answer» The element Z=114 has been discovered recently. It will belong to which of the following group: (a) Halogen family. (b) Carbon family. (c) Oxygen family. (d) Nitrogen family.

Discussion

885.	Which of the following gives an unsaturated hydrocarbon product when treated with conc. sulphuric acid
Answer» Which of the following gives an unsaturated hydrocarbon product when treated with conc. sulphuric acid

Discussion

886.	How nd' why metals react with water.........???
Answer» How nd' why metals react with water.........???

Discussion

887.	What is Y from the below reaction?CH3−CH2OHAlkaline KMnO4+Heat−−−−−−−−−−−−−−−−−−→Or acidified K2Cr2O7+HeatY
Answer» What is Y from the below reaction? $C H_{3} - C H_{2} O H A l k a l i n e K M n O_{4} + H e a t - ----------------- \to O r a c i d i f i e d K_{2} C r_{2} O_{7} + H e a t Y$

Discussion

888.	16.How many moles of oxygen atom present in 44gm of CO2
Answer» 16.How many moles of oxygen atom present in 44gm of CO2

Discussion

889.	28.Calculate frequency of x-rays when atomic number is 50 and a=b=1
Answer» 28.Calculate frequency of x-rays when atomic number is 50 and a=b=1

Discussion

890.	Which ions can conduct electricity? Anions or cations?
Answer» Which ions can conduct electricity? Anions or cations?

Discussion

891.	A mixture of N2 and H2is caused to react in a closed container to form NH3. The reaction ceases before either reactant has been totally consumed. At this stage,4 moles each of N2,H2,and NH3 are present. Then the weight of N2 And H2 present originally were respectively
Answer» A mixture of N2 and H2is caused to react in a closed container to form NH3. The reaction ceases before either reactant has been totally consumed. At this stage,4 moles each of N2,H2,and NH3 are present. Then the weight of N2 And H2 present originally were respectively

Discussion

892.	(a) What is the difference between an atom and a molecule?(b) Define relative molecular mass.
Answer» (a) What is the difference between an atom and a molecule? (b) Define relative molecular mass.

Discussion

893.	Question 11Why are decomposition reactions called the opposite of combination reactions? Write equations for these reactions.
Answer» Question 11 Why are decomposition reactions called the opposite of combination reactions? Write equations for these reactions.

Discussion

894.	The product formed in the following reaction will be: 2KHCO3+H2SO4→
Answer» The product formed in the following reaction will be: $2 K H C O_{3} + H_{2} S O_{4} \to$

894.

The product formed in the following reaction will be: 2KHCO3+H2SO4→

Answer»

The product formed in the following reaction will be:

$2 K H C O_{3} + H_{2} S O_{4} \to$

Discussion

895.	Question 14Which of the following gases can be used for storage of fresh sample of an oil for a long time?a) Carbon dioxide or oxygen(b) Nitrogen or oxygen(c) Carbon dioxide or helium(d) Helium or nitrogen
Answer» Question 14 Which of the following gases can be used for storage of fresh sample of an oil for a long time? a) Carbon dioxide or oxygen (b) Nitrogen or oxygen (c) Carbon dioxide or helium (d) Helium or nitrogen

Discussion

896.	30. If quantum number of element are given such as n,l,m,s then how to find period and group of element.
Answer» 30. If quantum number of element are given such as n,l,m,s then how to find period and group of element.

Discussion

897.	Explain the following briefly:(a) Sodium chloride dissolves in water but carbon tetrachloride is insoluble in water.(b) Helium does not form He2 molecule.(c) Pure water does not conduct electricity, but on adding sodium chloride to it, it starts conducting electricity.(d) Cl2 is a non-polar molecule, while HCl is a polar molecule.(e) Metals are electropositive.
Answer» Explain the following briefly: (a) Sodium chloride dissolves in water but carbon tetrachloride is insoluble in water. (b) Helium does not form He₂ molecule. (c) Pure water does not conduct electricity, but on adding sodium chloride to it, it starts conducting electricity. (d) Cl₂ is a non-polar molecule, while HCl is a polar molecule. (e) Metals are electropositive.

Discussion

898.	28. Electronegativity of carbon atoms? Sp2 hybridised or sp how to identify?
Answer» 28. Electronegativity of carbon atoms? Sp2 hybridised or sp how to identify?

Discussion

899.	what is the covalency of nitrogen? 3 or 4?and why it is not 5?
Answer» what is the covalency of nitrogen? 3 or 4? and why it is not 5?

Discussion

900.	in toluene the order of reactivity of each hydrogen
Answer» in toluene the order of reactivity of each hydrogen

Discussion

Explore topic-wise InterviewSolutions in .

(a) Why are alkali metals kept in kerosene oil? (b) What is : (i) basic lead carbonate and (ii) brown powder deposit on iron? (c) Why is hydrogen kept in the metal activity series?

Which group of elements is stored in oil due to their reactive nature with water and air?

Oxidising Agent + Hydrochloric Acid → Salt + Water + ___

An element, X has the following isotopiccomposition 200X : 90% 199X: 8% 202X : 2.0%. Theweighted average atomic mass of the naturallyoccurring element X is closest to(2) 202 amu(1) 201 amu(4) 200 amu(3) 199 amu

how many grams of Naoh are present in 250ml of 0.5M naoh solution ?

If x molecules of CH4 are removed from 44.8L of methane sample, then it was observed that 10 g of CH4 was remained . find the value of x.

The IP1, IP2, IP3, IP4 and IP5 of an element are 7.1, 14.3, 34.5, 46.8, 162.2 eV respectively. The element is likely to be -

If 25ml of a sulphuric acid solution reacts completely with 1.06 g of pure sodium carbonate, what is the normality of this acid solution?

State a safety precaution taken during the preparation of hydrochloric acid through funnel experiment.

27. What are rigid and elastic diatomic molecules?

When a glass rod dipped in ammonia solution is brought near vapours of hydrochloric acid we see the formation of a dense white fume. What is this dense white fume?

when 1-chloro-2,2-dimethyl propane is treated with NaOH /DMSO then reaction does not occur but when treated with aqueous NaOH then it give Sn1 reaction .why??

What are ions and molecules and compounds.

The property which is common between vinegar and curd is that they:

MnO2,PbO2 and red lead react with conc. HCl acid liberates Cl2. What is the common property being shown by these metal oxides ?

Explain the reactivity series of metals and arrange the given metals in the descending order of their reactivity. Aluminium, Copper, Potassium

The standard potential of the reaction H2O + e- gives 1/2 H2 + OH- at 298 K by using Kw(H2O) = 10 raise to the power -14 , is___

In any ionic crystal A has formed cubical closepacking and B atoms are present at everytetrahedral voids. If any sample of crystal containN' number of B atoms then number of A atoms inthat sample is

2CO2 (g)+2H2(g)→2CO(g)+ 2H2O(g) In this reaction ______ is getting oxidised.

How to find the charge of an ionic compound

The ‘green rust’ of copper is scrapped and dissolved in water. When litmus paper is dipped in it, what will be the change in colour ?

Which of the following sets of quantum numbers represents the highest energy for an atom?

How many elements were known at the time of Mendeleev?

Write a note on the position of metals and non-metals in the periodic table.

What would you observe in the following case:Ammonium hydroxide is first added in a small quantity and then in excess to a solution of copper sulphate.

38. What is the highest occupied molecular orbital in NO+ ?

Why is it not possible to remove stains with water alone?

What is the basis of behaviour as strong or weak field ligands for NH3 and H2O

Question 5 (a)State the following statement is True or False:Fossil fuels can be made in the laboratory.

What is an oxidation reaction ? Identify in the following reactions : (i) the substance oxidised (ii) the substance reduced. ZnO+C→Zn+CO

Which of the following options correctly represents the bond formed between hydrogen and chlorine in HCl?

why benzene is more stable?

The element Z=114 has been discovered recently. It will belong to which of the following group:(a) Halogen family.(b) Carbon family.(c) Oxygen family.(d) Nitrogen family.

Which of the following gives an unsaturated hydrocarbon product when treated with conc. sulphuric acid

How nd' why metals react with water.........???

What is Y from the below reaction?CH3−CH2OHAlkaline KMnO4+Heat−−−−−−−−−−−−−−−−−−→Or acidified K2Cr2O7+HeatY

16.How many moles of oxygen atom present in 44gm of CO2

28.Calculate frequency of x-rays when atomic number is 50 and a=b=1

Which ions can conduct electricity? Anions or cations?

A mixture of N2 and H2is caused to react in a closed container to form NH3. The reaction ceases before either reactant has been totally consumed. At this stage,4 moles each of N2,H2,and NH3 are present. Then the weight of N2 And H2 present originally were respectively

(a) What is the difference between an atom and a molecule?(b) Define relative molecular mass.

Question 11Why are decomposition reactions called the opposite of combination reactions? Write equations for these reactions.

The product formed in the following reaction will be: 2KHCO3+H2SO4→

Question 14Which of the following gases can be used for storage of fresh sample of an oil for a long time?a) Carbon dioxide or oxygen(b) Nitrogen or oxygen(c) Carbon dioxide or helium(d) Helium or nitrogen

30. If quantum number of element are given such as n,l,m,s then how to find period and group of element.

28. Electronegativity of carbon atoms? Sp2 hybridised or sp how to identify?

what is the covalency of nitrogen? 3 or 4?and why it is not 5?

in toluene the order of reactivity of each hydrogen