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.

Which of the following will give syn addition ?

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ANSWER :A::B::C
Discussion
2.

Which of the following can act as an electrophile?

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`CN-`
`OH-`
`H_2O`
`BF_3`

ANSWER :d
Discussion
3.

What is the wavelength of the light emitted when the electron in a hydrogen atom undergoes transition from an energy level with n=4 to an energy level with n=2 ? What is the colour corresponding to this wavelength ? (Rydberg constant =109, 677 cm^(-1))

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Solution :`bar(v)=R(1/n_(1)^(2)-1/n_(2)^(2))=109677 (1/2^(2)-1/4^(2)) CM^(-1) =20564.4 cm^(-1)`
`lambda =1/v=1/(20564.4 cm^(-1))=486xx10^(-7) cm=486xx10^(-9) m=486 nm`
The colour CORRESPONDING to this wavelength is blue.
Discussion
4.

What will be the effect on concentration by decrease the volume of vessel containing CO_((g)) + 3H_(2(g)) hArr CH_(4(g)) + H_2O_((g)) ?

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Solution :The concentration of reactants and pressure increases. As the VOLUME of vessel decrease TOTAL pressure increases. Now pressure is proportional to the concentration. So as the volume decrease concentration increases.
Concentration`PROP` pressure `prop`MOLE so as the volume decrease concentration of REACTANT increases as reactants have 4 mole and product is has 2 mole.
Discussion
5.

Which elements of group-1 have highest hydration enthalpy? Why?

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Solution :The hydration ENTHALPIES of alkali metal ions decrease with increase in ionic SIZES. `Li^(+)` has maximum degree of hydration and for this REASON lithium salts are mostly HYDRATED.
Discussion
6.

Write short notes on Metallic Hydrides.

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Solution :Metallic (Interstitial) Hydride: Metalic hydrides usually obtained by hydrogenation of METALS and alloys inwhich hydrogen occupies the interstitial ites (voids). Hence, they are called interstitial hydrides. These hydrides SHOW properties similar to parent metals and hence they are also know as metallic hydries. Most of the hydries are non-stoichiometric with variable compositon `(TiH_(1.5-1.8)" and "PdH_(0.6-0.8)`, some are relatively LIGHT, inexpensive and THERMALLY unstable which MAKES them useful for hydrogen storage applications.
Discussion
7.

Which is not a property of water ?

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It is a COLOURLESS and TASTELESS liquid.
There is no hydrogen BONDING in solid state of water.
It is an excellent solvent for transportation of IONS in plants and animals.
Ice is lighter than liquid water.

Solution :There is extensive hydrogen bonding in solid state OS water.
Discussion
8.

Three moles of B_(2)H_(6) are completely reactedwith methanol. The numberof moles of boron containingproduct formed is

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SOLUTION :Six :
`3B_(2)H_(6) + 8 MEOH RARR UNDERSET("Trimethylborate")(6B(Ome)_(3))+ 18H_(2)`
Discussion
9.

Use molecular orbital theory to explain why Be, molecule does not exist.

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Solution :The atomic no. (z) of Be is 4. This means that S ELECTRONS are to be FILLED in the M.O. of `Be_(2)`
The configuration is : `sigma1s^(2)sigma**1s^(2)sigma2s^(2)sigma**2s^(2)`:
`B.O.=1/2[N_(b)-N_(a)]=1/2[4-4]=0`
As bond order of `Be_(2)` is zero the MOLECULE of `Be_(2)` does not exit.
Discussion
10.

When one mole of the given compound reats with sodium metal then how many moles of H_(2) gas will release

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1 MOLE
1.5 mole
2 mole
0.5 mole

Answer :D
Discussion
11.

Write the reaction involved in formation of LiBH_4

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Discussion
12.

What changes are observed in atoms undergoing ionic bonding?

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Solution :The atom ATTAINS STABLE octet CONFIGURATION and FORMS electrostatic forces of attraction.
Discussion
13.

Which of the following is not a method of preparation of colloidal solution

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Electrical dispersion
Peptization
COAGULATION
Mechanical dispersion

Solution :The precipitation of a colloid through INDUCED AGGREGATION by the ADDITION of some suitable electrolyte is CALLED coagulation.
Discussion
14.

Which of the following is correct option for free expansion of an ideal gas under adiabatic condition ?

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`q=0, Delta T NE 0, W=0`
`q ne 0, Delta T = 0, w=0`
`q=0, Delta T =0, w=0`
`q=0, Delta T lt 0, w ne 0`

Solution :For FREE EXPANSION of an IDEAL gas under adiabatic condition, `q=0, Delta T=0, w=0`
Discussion
15.

Which is the decreasing order of strength of bases : OH^- , NH_2^(-), HC -=C^(-) and CH_3 CH_2^(-) ?

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`CH_3CH_2^(-) GT NH_2^(-) gt HC-=C^(-) gt OH^(-)`
`HC-=C^(-) gt CH_3CH_2^(-) gt NH_2^(-) gt OH^(-)`
`OH^(-) gt NH_2^(-) gt HC -=C^(-) gt CH_3CH_2^(-)`
`NH_2^(-) gt HC -=C^(-) gt OH^(-) gt CH_3CH_2^-`

ANSWER :A
Discussion
16.

What is the maximum probability for an electron to be present within the atomic orbital ?

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SOLUTION :`90 - 95%`
Discussion
17.

Which of the following will be the most hydrated salt ? (1) NaCl (2) MgCl_2 (3) AlCl_3 (4) SiCl_4

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SOLUTION :Smaller the CHARGE density `(q/r^(2))` , more is the EXTENT of HYDRATION.
Discussion
18.

Which of the following carbides on treatment with water give methane?

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`CaC_(2)`
`Be_(2)C`
`Al_(4)C_(3)`
`Mg_(2)C_(3)`

SOLUTION :`Be_(2)C+4H_(2)Oto2Be(OH)_(2)+underset("METHANE")(CH_(4))`
`Al_(4)C_(3)+12H_(2)Oto4Al(OH)_(3)+underset("Methane")(CH_(4))`
`CaC_(2)+2H_(2)OtoCa(OH)_(2)+underset("Acetylene")(C_(2)H_(2))`
`MgC_(3)+4H_(2)Oto2Mg(OH)_(2)+underset("PROPYNE")(HC-=C-CH_(3))`
Discussion
19.

What are the various factors due to which the ionization enthalpy of the main group elements tends to decrease down the group?

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Solution :ATOMIC size: With the increase in atomic size, the NUMBER of electron SHELLS increase. Therefore, the force that binds the electrons with the nucleus decreases. The ionization enthalpy thus decreases with the increase in atomic size.
Screening or shielding effect of inner shell electron: With the addition of new shells, the number of inner electron shells which SHIELD the VALENCE electrons increases. As a result, the force of attraction of the nucleus for the valence electrons further decreases and hence the ionization enthalpy decreases.
Discussion
20.

Which of the following hydrides conduct clectricity?

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`SiH_4 `
`B_2H_6`
`CH_4`
`KH`

SOLUTION :KH is a crystalline SOLID, molten state it conducts electricity as it possesses `K^(+) and H^(-)` ions
Discussion
21.

When 10 ml of hydrogen and 12.5 ml of chlorine are allowed to react the final mixture contains under the same conditions

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22.5 ML of HCl
12.5 ml of HCl
20 ml of HCl and 2.5 ml of chlorine
20 ml of HCl nly

Solution :`H_(2)+Cl_(2) rarr 2HCl`
Discussion
22.

Which of the following is not used for the purification of solid impurities?

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DISTILLATION
SUBLIMATION
CRYSTALLIZATION
none of these

Solution :All of these are effective to remove volatile ORGANIC compounds from SOLID impurities.
Discussion
23.

Which of the following transistions in hydrogen atom will require the highest amount of energy

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n=1 to n=2
n=1 to n=3
n=2 to n=1
n=3 to n=4

Solution :EXCITATION GAP is more for `1 to 2 `
Discussion
24.

Write short notes on the following (i) Raschig process. (ii) Dows process. (iii) Darzens process.

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Solution :(i) Raschig process: Chloro benzene is commerically prepared by passing a MIXTURE of benzene vapour, air and HCL over heated cupric chloride is reaction is called Raschig process.

(ii) Dows Process:
`underset("Chlorobenzene")(C_(6)H_(5)Cl+NaOH) underset(300atm)overset(350^(@)C) to underset("Phenol")(C_(6)H_(5)OH)+NACL`
This reaction is known as Dow's process.
(iii) Darzens process:

This reaction is known as Darzen's HALOGENATION.
Discussion
25.

Which is the unit of Dipole moment ?

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SOLUTION :D bye in SHORT D. It is a
1 D = `3.33564 XX 10^(-30)` cm
Discussion
26.

What is the molecular formula of Borazole ?

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`B_(2)H_(6)`
`B_(6)N_(6)H_(6)`
`B_(3)N_(3)H_(6)`
`B_(3)N_(3)H_(6)`

SOLUTION :Molecular formula of BORAZOLE is `B_(3)N_(3)H_(6)`
Discussion
27.

What is Kernel ?

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SOLUTION :According to Lewis Kernel is positively charged part with the NUCLEUS PLUS the INNER ELECTRONS
Discussion
28.

What do you mean by syngas ?

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Discussion
29.

What is the molecular formula of aluminium chloride ?

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SOLUTION :`Al_2 Cl_6`
Discussion
30.

Which of the following quantum numbers for orbitals in hydrogen atom has a greater energy for electrons ? (i) n=3, l=2 and m=+1(ii) n=3, l=2 and m=-1

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SOLUTION :Same ENERGY but DIFFERENT ORIENTATIONS
Discussion
31.

Which element accept one electron and get noble gas like configuration ?

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Solution :HYDROGEN ELEMENT accept one ELECTRON and get NOBLE gas like CONFIGURATION.
Discussion
32.

Which of the following species have five unpaired electrons ?

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`Cr^(3+)`
`Mn^(2+)`
`Fe^(3+)`
`Cu^(2+)`

ANSWER :B::C
Discussion
33.

Which of the following is not the characteristics of an arene?

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A. Resonance
B. DELOCALIZATION of pie electrons
C. More stability
D. UNDERGOES electrophilic addition reaction

Answer :B
Discussion
34.

Which elements of group-I and group-ll are differ from the other elements of same group?

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SOLUTION : Lithium and beryllium, the first elements of Group-1 and Group-2 RESPECTIVELY exhibit some properties which are different from those of the other members of the RESPECTIVE group. Lithium shows similarities to MAGNESIUM and beryllium to ALUMINIUM in many of their properties.
Discussion
35.

Why alkali metals are soft and have low melting points?

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Solution :ALKALI METALS have only one VALENCE electron per metal atom. As a result, the binding energy of alkali metal ions in the close-packed metal lattices are WEAK. Therefore, these are soft and have low melting point
Discussion
36.

Which among the following statement is false

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The ADSORPTION may be monolayered or multilayered
particle size of adsorbent will not AFFECT the amount of adsorption
Increase of PRESSURE increases amount of adsorption
Increase of TEMPERATURE may decrease the amount of adsorption

Answer :B
Discussion
37.

What is the pH of normal rain water? What happens to the pH of rain water if it is accompanied by a thunderstorm and why?

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Solution :pH of normal rain WATER is about 5.6 When rain is accompanied by a thunderstorm `N_2` and `O_2` of the air COMBINE to FORM NO which is further oxidized to `NO_2` and DISSOLVES in rain water to form `HNO_3`. Hence rain water becomes more acidic and hence pH falls below 5.6.
Discussion
38.

Which d-orbitals has its four lobes along the axes

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`d_(XY)`
`d_(x^(2)-y^(2))`
`d_(Z^(2))`
`d_(XZ)`

Answer :B
Discussion
39.

X and Y are respectively :

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ANSWER :A
Discussion
40.

Which of the following statements is/are correct with respect to behaviour of real gas.

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For every vander Waal gas at CRITICAL condition, attractive force will be dominant. 
The LIQUID and gaseous STATE can be distinguished only if the temperature is below the gas's critical temperature, 
At very HIGH pressures, real gases occupy greater VOLUME as compared to ideal gas having samo moles at same temperature and exerting same pressure. 
For a real gas the 'y' intercept of `(PV_m)/(T)` vs curve where 'P' represents pressure (in atm), `V_m` represents molar volume and ‘T’ represents temperature in kelvin is equal to 0.0821 atm-litre/mol Kelvin. 

Solution :At critical state `Z < 1 implies` attractions dominate only below `T_c`, gas can be liquified at higher P, `Z > 1 implies V_r > V_i`.
Discussion
41.

Write suitable chemical equations to show their nature.

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SOLUTION :(i)`B_2O_3, SiO_2, CO_2` it reacts with bases to form salts . It reacts with NaOH.
`B_2O_3+2NAOH to underset"SODIUM metaborate"(2NaBO_2)+H_2O`
`SiO_2+2NaOH oversetDeltato underset"Sodium silicate"(Na_2SiO_3) + H_2O`
`CO_2 + 2NaOH to underset"Sodium carbonate"(Na_2CO_3) + H_2O`
(ii) Due to amphoteric nature of both `Al_2O_3` and `PbO_2` they can react with both acid and base.
`Al_2O_3 + 2NaOH to underset"Sodium meta aluminate"(NaAlO_2+ H_2O)`
`Al_2O_3 + 3H_2SO_4 to Al_2(SO_4)_3 + 3H_2O`
`PbO_2 + 2NaOH to underset"Sodium plumbet"(Na_2PbO_3) + H_2O`
`2PbO_2 + 2H_2SO_4 to 2PbSO_4 + 2H_2O + O_2`
(III) `Tl_2O_3` it reacts with acids to form salts . It reacts with HCl to form thallium chloride.
`Tl_2O_3 + 6HCl to 2TlCl_3 + 3H_2O`
Discussion
42.

Why alkane is used as fuel ?

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Solution :High ENERGY is PRODUCED during combustion reaction of alkane compound and hence, alkane is used as FUEL.
Discussion
43.

What do you understand by rest mass of the electron ? What is its value on the unified scale ? How is the mass of the electron related to its velocity ? What will be the mass of the electron if it travels with velocity equal to the velocity of light ?

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Solution :Rest mass of the electron is the mass of the electron when it is moving with a velocity much less than the velocity of light. Its value `= 9.1095 xx 10^(-31)kg or 0.0005486u`. When the electron is moving with velocity v, its mass is given by : `m = (m_("rest"))/(SQRT(1 - ((v)/(c))^(2)))` where c is the velocity of light.
Thus, when electron is moving with the velocity of light so that v = c, its mass is infinite.
Discussion
44.

Which of the following contains both covalent and ionic bond?

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`CCl_(4)`
`CaCl_(2)`
`NH_(4) Cl`
`H_(2) O `

Solution :N/A`(H-UNDERSET(H)underset(|)overset(H)overset(|)N-N)Cl^(-)`
Discussion
45.

What happens if ferric salt is added to the equilibrium of thr reaction between Fe^(3+) and SCN^(-) ions ?

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SOLUTION :RED COLOUR DEEPENS.
Discussion
46.

Which of the following is (are) correct order(s) for basic strength ?

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`NaOHgtNH_(4)OHgtH_(2)O`
`NH_(3)gtN_(2)H_(4)gtNH_(2)OH`
`NH_(3)gtH_(2)OgtHF`
`OH^(-)ltC_(2)H^(-)ltNH_(2)^(-)ltC_(2)H_(3)^(-)ltC_(2)H_(5)^(-)`

Answer :A::B::C::D
Discussion
47.

The value of equilibrium constant of reaction HI_((g))hArr1/2H_(2(g))+1/2I_(2(g)) is 8.0. The equilibrium constant of the reaction , H_(2(g))+I_(2(g))hArr2HI_((g)) will be

Answer»

`1/8`
`1/16`
`16`
`1/64`

Solution :FORMATION `ALPHA(1)/("DISSOCIATION")`
Then when the reactants & products CONCENTRATION are doubled, hence equilibrium constant is also doubled.
Discussion
48.

What is the molecular mass or molar volume at STP or NTP and SATP ?

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Solution :At STP
Molar VOLUME or ideal GAS = 24.413996 L
But in calculation we can take 22.71098 L, 22.71 L
Molar volume of ideal gas at SATP `= 24.787 L mol^(-1)`.
Discussion
49.

What is the volume strenth of H_(2)O_(2)?

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SOLUTION :Volum strenth `=5.6xx"normality and"`
VOLUME STRENGTH `=11.2xx"MOLARITY."`
Discussion
50.

What is the molecular formula of plaster of paris?

Answer»

`2CaSO_(4).H_(2)O`
`2CaSO_(4).2H_(2)O`
`CaSO_(4).2H_(2)O`
`CaSO_(4).3H_(2)O`

Answer :A
Discussion