Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

SiO_(4)^(4-) ion has geometry

Answer»

TRIANGULAR
Tetrahedral
PENTAGONAL bipyramidal
Linear

Answer :B
Discussion
2.

SiO_(4)^(4-)"ion" has __________ geometry

Answer»

Trinagular
Tetrahedral
Linear
Pentagonal bipyramidal

ANSWER :B
Discussion
3.

SiO_(2)is ………………..

Answer»

PLASTICIZER
FILLER
ANTIOXIDENT
NONE of these

Solution :filler
Discussion
4.

SiO_(2) is a

Answer»

FLUX
gangue
slag
catalyst

Answer :A::B
Discussion
5.

SiO_(2) is a:

Answer»

flux
gangue
slag
catalyst

Answer :A::B
Discussion
6.

Single electrode potential is

Answer»

The potential DEVELOPED at any electrode of a cell at all times.
The potential DIFFERENCE between an electrode and the SOLUTION AROUND it only at 298 K.
The potential developed at the electrode when reactants and products are of unit activity.
The potential difference between an electrode and the solution around it , is at equilibrium

Answer :D
Discussion
7.

Since N, N-diethylbenzene sulphonamide does not contain any hydrogen atom attached to N-atom, it is not __________ and hence __________ in alkali.

Answer»


ANSWER :ACIDIC, INSOLUBLE
Discussion
8.

Single bond between sulphure atoms is present in

Answer»

`H_2S_2O_7`
`H_2S_2O_8`
`H_2S_2O_6`
`H_2S_2O_3`

ANSWER :C
Discussion
9.

Since, Grignard reagents resemble carbanion, so they are strong nucleophile and strong base. Their most useful nucleophilic reaction is addition to carbonyl group. Arrange the following compounds in decreasing order of nucleophilic addition reaction :

Answer»

`RgtPgtSgtQ`
`PgtQgtRgtS`
`QgtRgtSgtP`
`RgtSgtPgtQ`

SOLUTION :N//A
Discussion
10.

Since, Grignard reagents resemble carbanion, so they are strong nucleophile and strong base. Their most useful nucleophilic reaction is addition to carbonyl group. Which of the following compounds will not give acid-base reaction with RMgX?

Answer»

`CH_(3)-CH_(2)-CL`
`CH_(3)OH`

`H_(2)S`

Solution :N//A
Discussion
11.

Since, lanthanides relased electron from 4f, 5d and 6s orbitals, they show

Answer»

fixed oxidation state
variable oxidation state
TWO oxidation state
ONE oxidation state

ANSWER :B
Discussion
12.

Since glucose is converted to fructose by this method, what can you say about the configuration of C_3,C_4 " and "C_5 in the sugars.

Answer»

Solution :
Here aldohexosereacts with one MOLECULE of phenylhdrazine which condenses with the aldehyde group to give phenylhydrazone. When warmed with axcess of phenyl hydrazine, the SECONDARY alcoholic group adjacent to the aldehyde group is oxidised by another molecule of PHENYLHYDRAZINE, to a ketonic group. With this ketonic group, the third molecule of phenylhydrazine condenses to GIVEN osazone. The phenylhydrazinyl group is transferred from osazone to `C_6H_5CHO` giving `C_6H_5CH=N.NHC_6H_5` and a dicarbonyl compound called an osone. The more reactive aldehyde group of the osone is REDUCED, not the less reactive keto group and it give the 2-ketohexose.
Discussion
13.

Since both aldehydes and ketones possess carbonyl functional group, they undergo similar chemical reactions. (i) Explain the structure of carbonyl group.

Answer»


Answer :Carbon in CARBONYL GROUP is `sp^2` hybridised. Carbonyl group is planar. BOND ANGLE is `120^@`.
Discussion
14.

Since both aldehydes and ketones possess carbonyl functional group, they undergo similar chemical reactions. (ii) Explain Aldol condensation with an example.

Answer»


ANSWER :REFER to the answer of HSE MARCH 2014 (a)
Discussion
15.

Since all lanthanides and actinides belong to group IIIB or 3rd group they have common oxidation state of +3 as the most stable state. In addition to +3, they also show +2 and +4 states also. M+2 states they are good reducing agents. Actinides show higher oxidation states of +5, +6 and +7. For them +3 state is not the most stable state especially for the flfst four elements Based upon the information above answer the following questions Lanthanides which show powerful reducing action in +2 state

Answer»

La, OD, HO
Er,LU,Eu
Th,YB,CE
Nd,Sm,Tb

Solution :Ce can SHOW +4
Discussion
16.

Since all lanthanides and actinides belong to group IIIB or 3rd group they have common oxidation state of +3 as the most stable state. In addition to +3, they also show +2 and +4 states also. M+2 states they are good reducing agents. Actinides show higher oxidation states of +5, +6 and +7. For them +3 state is not the most stable state especially for the flfst four elements Based upon the information above answer the following questions Actinides which show higher uxidastion state +5, +6 and +7 states and respectively are

Answer»

TH,Pa and Am
Am,CM and U
Pa,U and Ac
Pa,U and Np

Solution :[Pa= +5,U=+6,Np=+7]
Discussion
17.

Since 1891 lighting lamps have been manufactured in the Netherlands. The improvement today in comparison to the first lamp is enormous , especially with the intorduction of the gas discharge lamps. The life- time has increased by orders of magnitude . the colour is also an important aspect. Rare earth metal compunds like CeBr_(3) are now included to reach a colour temperature of 6000K in the lamp the compounds are ionic solids at room temperature , and upon heating they sublime partially to give a vapour of neutral metal halide molecules . To achieve a high vapour pressure, the sublimation enthalpy should be as low as possible. Conclusion in relation to the previous answers. was adding CsBr a good idea ? Mark the correct answer. implies Adding CsBr is counterproductive. implies AddingCsBr has no influence implies Adding CsBr is advantageous implies From these data no clear answer can be given.

Answer»


SOLUTION :N//A
Discussion
18.

Since 1891 lighting lamps have been manufactured in the Netherlands. The improvement today in comparisonto the first lamp is enormous , especially with the intorduction of the gas discharge lamps. The life- time has increased by orders of magnitude . the colour is also an important aspect. Rare earth metal compunds like CeBr_(3) are now included to reach a colour temperature of 6000K in the lamp the compounds are ionic solids at room temperature , and upon heating they sublime partially to give a vapour of neutral metal halide molecules . To achieve a high vapour pressure, the sublimation enthalpy should be as low as possible. Calculate the enthalpy of sublimation of CeBr_(3) (in intergers, be aware of signs). Attemps to make a better lamp have been undertaken by adding a stoichiometric amount of CsBr to the CeBr_(3) in the lamp leading at room temperature to solid CsCeBr_(4) lattice has a NaCl structure with Cs as cations and tetrahedral CeBr_(4)^(-) as complex anions. Sublimation of CsCeBr_(4) leads to a vapour of CsBr and CeBr_(3) molecules.

Answer»


SOLUTION :N//A
Discussion
19.

Since 1891 lighting lamps have been manufactured in the Netherlands. The improvement today in comparison to the first lamp is enormous , especially with the intorduction of the gas discharge lamps. The life- time has increased by orders of magnitude . the colour is also an important aspect. Rare earth metal compunds like CeBr_(3) are now included to reach a colour temperature of 6000K in the lamp the compounds are ionic solids at room temperature , and upon heating they sublime partially to give a vapour of neutral metal halide molecules . To achieve a high vapour pressure, the sublimation enthalpy should be as low as possible. Calculate the enthalpy of sublimation fo CsCeBr_(4) (in integers) Use the Born-Lande formula for all steps in the process and report the separate energies also (be aware of the signs). The CeBr_(4)^(-) anion is a teteahedron and in which the ratio between the edge and the destance between a corner of the tetrahedron and the centre of gravity (body - radius) amounts to (2sqrt(6))//3 = 1.33 . The Born exponent of the CsBr is 11.The radius of Cs is 0.181 nm.

Answer»


SOLUTION :N//A
Discussion
20.

Since 1891 lighting lamps have been manufactured in the Netherlands. The improvement today in comparisonto the first lamp is enormous , especially with the intorduction of the gas discharge lamps. The life- time has increased by orders of magnitude . the colour is also an important aspect. Rare earth metal compunds like CeBr_(3) are now included to reach a colour temperature of 6000K in the lamp the compounds are ionic solids at room temperature , and upon heating they sublime partially to give a vapour of neutral metal halide molecules . To achieve a high vapour pressure, the sublimation enthalpy should be as low as possible. Give a thermochemical cycle (law of Hess) for sublimation of CeBr_(3) , via vapour of mononucler ions (H_(1) =H_("lattice"), H_(e) = H_("electrostatic"), H_(s) =H_("sublimation") , H is not absolute , H means DeltaH) H_(s)=-H_(1) + H_(e) The lattice energy of the solid can be calculatedusing the Baron -Lande formula, H_(1)=d(Z+Z-Ae^(2))/(r_(+) +r_(-))(1-(1)/(n)) The factorFe^(2) (necessary in order to calculate the lattice is 2.985. The Borm exponent n is 11. The charge of the ions Z_(+) and Z_(_) are integer number (Z is negative ). For the calculation of the energy of gaseous CeBr_(3) (when formed from ions) the same Born- Lande formula can be used without A. The structure of CeBr_(3) in the gas phase is planer triangular . The radius of Ce^(3+) is 0.115 nm and of Br is 0.182nm.

Answer»


SOLUTION :N//A
Discussion
21.

Since 1891 lighting lamps have been manufactured in the Netherlands. The improvement today in comparison to the first lamp is enormous , especially with the intorduction of the gas discharge lamps. The life- time has increased by orders of magnitude . the colour is also an important aspect. Rare earth metal compunds like CeBr_(3) are now included to reach a colour temperature of 6000K in the lamp the compounds are ionic solids at room temperature , and upon heating they sublime partially to give a vapour of neutral metal halide molecules . To achieve a high vapour pressure, the sublimation enthalpy should be as low as possible. Give the reaction equations of the thermochemical cycle (Law of Hess) for this process in which some steps involve CeBr_(4)^(-) ions monmelecular ions and /or neutral molecules in the phase. Step 1: overset(+H_(1))rarr""+ Step 2 : +""overset(+H_(2)) rarr Step 3 : +""overset(+H_(3))rarr Step 4: +""overset(+H_(4))rarr Total : (CsCeBr_(4))_("lattice") overset(+H_("total"))rarr (CeBr_(3))_("molecules") + (CsBr)_("molecules")

Answer»


SOLUTION :N//A
Discussion
22.

Simplest biological amino acid is

Answer»

ALANINE
LYSINE
HISTIDINE
GLYCINE

SOLUTION :
Discussion
23.

Simplest alkyne is represented by

Answer»

CH
`CH_2`
`C_2H_2`
`C_2H_4`

ANSWER :C
Discussion
24.

Simplest proteins has one peptide linkage. It is

Answer»

TRIPEPTIDE
dipepetide
tetrapeptide
oligopeptide

ANSWER :B
Discussion
25.

Simple proteins bonded with a non-protein prosthetic group ( acting as cofactor ) are called

Answer»

SIMPLE proteins
Conjugated proteins
Proteonic proteins
None

Answer :B
Discussion
26.

Simple distillation is used to separate liquids which differ in their boiling point by :

Answer»

`5^@C`
`10^@C`
`30^@ -80^@C`
Less then `20^@C`

ANSWER :C
Discussion
27.

Simple aliphatic acids having upto four carbon atoms are ______ in water.

Answer»

SOLUTION :MISCIBLE
Discussion
28.

Simple and mix ethers can be prepared by which process ?

Answer»

WURTZ REACTION
Etherification reaction
Grignard reaction
WILLIAMSON's reaction

Solution : Williamson.s reaction
Discussion
29.

Similarity of fluorine and oxygen may not be attributed to

Answer»

their ATOMIC and IONIC radii are closely similar
the ATOMS of both elements are RESTRICTED to an octet of electrons in their valence shell
both of them are highly electronegative elements
both FORM stable pr-pa multiple bonds with themselves

Answer :A
Discussion
30.

Silverware turns black after a period of time due to formation of

Answer»

nitrate coating on SILVER
SULPHIDE coating on silver
chloride coating on silver
oxide coating on silver

Solution :Silver comes in contact with `H_(2)S` of air and forms silver sulphide which is black in colour.
`2Ag + H_(2)S to Ag_(2)underset("black")(S + ) H_(2)`
Discussion
31.

Silvering of mirror is done by

Answer»

`AgNO_(3)`
`Ag_(2)O_(3)`
`Fe_(2)O_(3)`
`Al_(2)O_(3)`

Answer :A
Discussion
32.

Silver with impurity of lead is refined by .........

Answer»

Vapour PHASE refining 
ELECTROLYTIC refining 
Cupellation 
CHROMATOGRAPHY 

ANSWER :C
Discussion
33.

Silver sulphide is heated in the presence of air and common salt to convert it to sodium sulphate. This is an example of

Answer»

sulpliatising ROASTING
OXIDISING roasting
chloridising roasting
CALCINATION process

Answer :C
Discussion
34.

Silver on warming in O_3 the reaction is

Answer»

Oxidaition of the METAL
Formation of ozonide
Alternate OXIDATION of the metal and reduction of OXIDE takes place
Reduction of metal

Answer :C
Discussion
35.

Silver salt method is used todeterminemolecular weight of

Answer»

Organic ACIDS
Organic BASES
Both acids and bases
None of these

Solution :(a) is CORRECT because acids will react with `AgNO_(3)` to form silver salt whereares bases do not react.
`:.` (B), (c ) and (d) are not react.
Discussion
36.

Silver possesses metallic lusture because:

Answer»

It is noble metal
It is COATED with the OXIDE of silver
Valency electrons ABSORB WHITE LIGHT completely
Valency electrons absorb and eject white light

Answer :D
Discussion
37.

Silver salt of a fatty acid on refluxing with an alkyl halide gives an

Answer»

ACID
Ester
AMIDE
AMINE

Answer :C
Discussion
38.

Silver salt of a diabsic acid contains 71.05 % of Ag. M.Wt of acid is ..... x 10

Answer»


SOLUTION :`E=(("Wt of silver salt")/("Wt of silver") XX 108 -107)`, `M.Wt=E xx "VALENCY"=90`
Discussion
39.

Silver obtained from argentiferrous lead containing lead impurity is purified by

Answer»

Distillation
Froth floatation
CUPELLATION
Treatment of KCN

Solution : Cupellation : If metal possess the IMPURITY o ANOTHER metal whihh forms volatile OXIDE. Then cupellation method is used.
Discussion
40.

Silver obtained by argentiferrous lead is purified by:

Answer»

DISTILLATION
FORTH floatation
Cupellation
Reacting with KCN

Answer :C
Discussion
41.

Silver obtained from argentiferous lead is purified by :

Answer»

DISTILLATION
FROTH floatation
Cupellation
Reaction with KCN

Answer :C
Discussion
42.

Silver nitrate solution when added to a colorless aqueous solution E forms a white precipitate which dissolves in excess of E. If the white precipitate is heated with water it turns black and the supernatant solution gives a white precipitate with acidified barrum nitrate solution. Therefore, E is :

Answer»

`Na_(2)S`
`Na_(2)S_(2)O_(3)`
`Na_(2)SO_(3)`
`Na_(2)SO_(4)`

Answer :B
Discussion
43.

Silver nitrate solution is kept in brown bottles in laboratory because:

Answer»

it REACTS with ordinary bottles
brown bottles cut the PASSAGE of LIGHT through
brown bottles do not react with it
ordinary bottles catalyst its decomposition

Answer :B
Discussion
44.

Silver nitrate solution gives a red precipitate with :

Answer»

SODIUM iodide
Potassium CHLORIDE
CALCIUM nitrate
Sodium chromate

ANSWER :D
Discussion
45.

Silver nitrate solution is gradually added to an aqueous solution containing 0.01 M each of chloride, bromide and iodide ions. The correct sequence in which the halides will be precipitated is

Answer»

`Br^(-) ,CI^(-),I^(-)`
`I^(- ),CI^(-) ,Br^(-)`
`I^(-) ,Br^(-),CI^-`
`Br^(-) ,I^(-) ,CI^(-)`

Solution :`K_(sp)`for ` AG CI ,AgBr` andAglare `1.8 xx 10^(-10) , 5.0 xx 10^(-13)and 8.3 xx 10^(-17) `respectivelyLowerthe solubilityproductmoreeasilyitgetsprecipitated .
Discussion
46.

Silver nitrate on heating gives

Answer»

`AgO and NO_(2)`
`AgO, NO and O_(2)`
`AG and NO_(2)`
`Ag, NO_(2) and O_(2)`

SOLUTION :`2AgNO_(3)OVERSET("RED HOT")rarr 2Ag+2NO_(2)+O_(2)`
Discussion
47.

Silver nitrate produces a black stain on skin due to :

Answer»

Its corrosive action
Its REDUCTION to METALLIC SILVER
Its STRONG reducing action
The formation of a complex compound

ANSWER :B
Discussion
48.

Silver nitrate, on heating at molerate temperature gives

Answer»

`Ag_(2)O`
`AgNO_(2)`
`O_(2)`
Both (B) and (C)

Solution :`2AgNO_(3)overset("Moderate")underset("TEMP.")rarr 2AgNO_(2)+O_(2)`
(a) is not possible because it is unstable.
Discussion
49.

Silver nitrate is usually kept in coloured bottles because it is:

Answer»

oxidised in AIR
decomposes in sunlight
explodes in sunlight
reacts with air in sunlight

Answer :B
Discussion
50.

Silver nitrate is usually supplied in coloured bottles because it is:

Answer»

Oxidised in AIR
Decomposed in sunlight
Explodes in sunlight
Reactive TOWARDS air in sunlight

Answer :B
Discussion