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.

What is Hydrides ? Give its types and Explain.

Answer»

Solution :Dihydrogen, under certain REACTION conditions, combines with almost all elements, except noble gases, to FORM binary COMPOUNDS, called hydrides.
If .E. is the symbol of an element then hydride can be EXPRESSED as `EH_X` (e.g., `MgH_2`) or `E_mH_n` (e.g., `B_2H_6`).
The hydrides are classified into three categories:
(i) Ionic or saline or saltlike hydrides
(ii) COVALENT or molecular hydrides
(iii) Metallic or non-stoichiometric hydrides
Discussion
2.

Which of the following is amphoteric

Answer»

`Li_(2)O`
`BeO`
`Bao`
`Cs_(2)O`

SOLUTION :"BeO" is AMPHOTERIC oxide
`underset(("Basicoxide"))(BeO+2HCl) to BeCl_(2)+H_(2)O`,
`underset(("Acidicoxide"))(BeO+2NaOH) to Na_(2)BeO_(2)+H_(2)O`
Discussion
3.

Which of the following formulae represent an alkane?

Answer»

`C_10H_20`
`C_7H_16`
`C_5H_8`
`C_9H_10`

ANSWER :B
Discussion
4.

Which of the following statement is/are correct ?

Answer»

METALLIC hydries are deficient in hydrogen
Metallic HYDRIDES conduct HEAT an electricity
Ionic hydrides do not conduct electricity in SOLID state
Ionic hydrides are very good conductors of electricity in solid state

SOLUTION :Ionic hydrides does not posses any ions in solid state, so they do not conductelectricity in solid state.
Discussion
5.

Which of the following alkynes can be identified and distinguished from the rest of the alkynes on reaction with ammoniacal silver nitrate to gave a white presipitate?

Answer»

`CH_(3)C-=C-CH_(3)`
`CH_(3)CH_(2)C-=CH`
`CH_(3)CH_(2)C-=C CH_(3)`
`CH_(3)C-=C CH_(2)CH_(2)CH_(3)`

Solution :Only terminal alkynes REACT with ammoniacal SILVER NITRATE to give white PRECIPITATE of silver ACETYLIDES.
Discussion
6.

The values that are useful in writing chemical formulae and in calculation of oxidation states are

Answer»

IONISATION potential
Electron affinity
Electronegativity
Metallic character

Answer :C
Discussion
7.

Which molecular out of the following does not contain unpaired electrons ?

Answer»

`N_(2)^(+)`
`O_(2)`
`O_(2)^(2-)`
`B_(2)`

SOLUTION :`N_(2)^(+) = KK sigma_(2S)^(2) sigma_(2s)^(**2) pi_(2_(p_(x)))^(2) pi_(2_(p_(y)))^(2) sigma_(2_(p_(z)))^(1)`
`O_(2) = KK sigma_(2s)^(2) sigma_(2s)^(**2) sigma_(2p_(z))^(2) pi_(2_(p_(x)))^(2) pi_(2_(p_(y)))^(2)pi_(2_(p_(x)))^(**1)pi_(2_(p_(y)))^(**1) `
`O_(2)^(2-) = KK sigma_(2s)^(2) sigma_(2s)^(**2) sigma_(2p_(z))^(2) pi_(2_(p_(x)))^(2) pi_(2_(p_(y)))^(2)pi_(2_(p_(x)))^(**2)pi_(2_(p_(y)))^(**2) `
`B_(2) = KK sigma_(2s)^(2) sigma_(2s)^(**2)pi_(2_(p_(x)))^(1)pi_(2_(p_(y)))^(1) `
thus , `O_(2)^(2-)`has no unpaired electrons.
Discussion
8.

What is the value of pH and pK_b of mix solution of ammonium hydroxide and ammonium chloride ? Why ?

Answer»

Solution :`PH APPROX pK_b approx` 9.25
because in it taken `[NH_4^+] approx [NH_3]`
So, LOG `(["conjugate acid", NH_4^+])/(["base", NH_3])`=log 1 = ZERO
So, pH=`pK_b`
Discussion
9.

When Zoclite which is hydrated Sodium Aluminium Silicate, is treated with hard water, the sodium ions are exchanged with

Answer»

`H^(+)` IONS
`CA^(2+)` ions
`SO_4^(2-)` ions
`Mg^(2+)` ions

Solution :b) `Ca^(2+)+ 2H^(+) -" RESIN" to Ca"(Resin)"_2 + 2H^(+)`
d) `Mg^(2+) + 2H^(+) -" Resin" to Mg("Resin")_2 + 2H^(+)`
Discussion
10.

What is oxidation number of S in H_(2)SO_(5) ?

Answer»

SOLUTION :The oxidation number of S in `H_(2)SO_(5) is +6.
Discussion
11.

Which of the following decreases the dissolved oxygen in water?

Answer»

ORGANIC MATTER
FLOURIDES
Carbonates
Methyl Hg

Solution :Organic matter
Discussion
12.

What is the correct order of acid catalysed hydation of following alkenes ? (I)CH_2=CH_2(II)CH_3-CH=CH_2(III)(CH_3)_2C=CH_2(IV)CH_3-CH=CH-CH_3

Answer»

III GT I gt II gt IV
III gt IV gt II gt I
II gt IV gt III gt I
I gt II gt III gt IV

Answer :B
Discussion
13.

The reagent that can be used to distinguish between phenol and ethanoic acid is

Answer»

AMMONIACAL silver NITRATE SOLUTION
Fehling solution
Sodium carbonate solution
Phenolphthalein

Solution :`HCOOH` reduces ammoniacal silver nitrate solution i.e., TOLLEN's REAGENT but acetic acid does not
Discussion
14.

Which is the actual order of ions with respect to ionic radius?

Answer»

`N^(3-) gt O^(2-) gt F^(-) gt NA^(+)`
`N^(3-) gt Na^(+) gt O^(2-) gt F^(-)`
`O^(2-) gt F^(-) gt Na^(+) gt N^(3-)`
`Na^(+) gt O^(2-) gt N^(3-) gt F^(-)`

ANSWER :a
Discussion
15.

Whether the following redox reaction is oxidation and which is reduction? Zn to Zn^(2+)+2e^(-)

Answer»

SOLUTION :OXIDATION
Discussion
16.

The structure of 4-methylpent-2ene is

Answer»

`(CH_(2))_(2)CH-CH_(2)CH=CH_(2)`
`(CH_(3))_(2)Ch-CH=CH-CH_(3)`
`(CH_(3))_(2)CH-CH_(2)-CH=CH-CH_(3)`
`(CH_(3))_(2)C=CH-CH_(2)-CH_(3)`

SOLUTION :`(CH_(3))_(2)CH-CH=CH-CH_(3)`
Discussion
17.

What is the number of photons of light with a wavelength of 4000 pm that provide 1J of energy ?

Answer»

Solution :`lamda = 4000" pm " = 4000 xx 10^(-12) m = 4XX 10^(-9) m`
`E = Nhv = N h(c)/(lamda) :. N = (E xx lamda)/(h xx c) = ((1J) xx (4xx 10^(-9) m))/((6.626 xx 10^(-34) Js) (3.0 xx 10^(8) MS^(-1))) = 2.012 xx 10^(16)` photons
Discussion
18.

Which one is an example of gel

Answer»

Soap
Cheese
Milk
Fog

Answer :B
Discussion
19.

Which of the following species is non-linear ?

Answer»

`ICI_(2)^(-)`
`I_(3)^(-)`
`N_(3)^(-)`
`CIO_(2)^(-)`

SOLUTION :`ICI_(2)^(-)` = LINEAR , `I_(3)^(-)` = linear , `N_(3)^(-)` = linear , `ClO_(2)^(-) = `
angular due to `sp^(3)` hybridization of Cl-atom
Discussion
20.

Which of the following reactions does occur as shown (i.e., forward is favoured)

Answer»

`CH_3 -= C^(-) Na^(+) + CH_3CO_2 H to CH_3CO_2^(-) Na^(+) + CH_3C -= CH`
`CH_3C-= C^(-) Na^(+) + CH_3OH to CH_3O^(-)Na^(+) + CH_3C -= CH`
`CH_3C -= CH + NaNH_2 to NH_3 + CH_3C-= C^(-) Na^+`
`CH_3C -= CH + NaOH to H_2O + CH_3C -= C^(-) Na^(+)`

SOLUTION :Acid-Base REACTIONS are FAVOURED from STRONG to weak direction. Order of acidic strength is
`CH_3 COOH GT CH_3 - OH gt CH_3 - C -= CH gt NH_3`
Discussion
21.

Which of the following carbanion is most stable

Answer»

`CH_(3)CH_(2)^(-)`
`CH_(2)=CH^(-)`
`CH EQUIV C^(-)`
`CH_(3)`

SOLUTION :% `alpha` stability as carbanion
Discussion
22.

What is SI units of coefficient of viscosity ? How is it related to poise ?

Answer»

SOLUTION :SI unit=kg `m^(-1)s^(-1)`
Poise =1 g `CM^(-1)s^(-1)"" :. "" 1 "Poise"=10^(-1) kg ^(-1)s^(-1)=(1)/(10)`th of SI unit.
Discussion
23.

The value of enthalpy change(DeltaH ) for the reactionC_(2)H_(5)OH(l) +3O_(2)(g)rarr 2CO_(2)(g) +3H_(2)O(l) at 27^(@)C is -1366 kJ mol^(-1). The value of internal energy change for the above reaction at thistemperature will be

Answer»

`-1371.5 kJ `
`-1369.0 kJ `
`- 1364.0 kJ`
`-1361.5kJ `

Solution :`C_(2)H_(5)OH(l) + 3O_(2)(g) rarr2CO_(2)(g) + 3H_(2)O(l)`,` Deltan_(g)=2-3= -1`
`DeltaU = DeltaH -Deltan_(g)RT`
`= - 1366.5 kJ mol^(-1) - ( -1) XX 8.314 xx 10^(-3) kJ K^(-1)mol^(-1) xx 300K`
`= - 1366.5 + 0.8314 xx 3 kJ mol^(-1)`
`=- 1366.5 +2.4942 = - 1364kJ mol^(-1)`
Discussion
24.

Write preparation of diborane and give physical and chemical properties of it.

Answer»

Solution :Preparation :
The simplest boron hydride known, is diborane. It is prepared by treating boron trifluoride with `LiAlH_4` in diethyl ETHER.
`4BF_3 + 3LiAlH_4 to 2B_2H_6+ 3LiF + 3AlF_3`
A convenient laboratory method for the preparation of diborane involves the oxidation of sodium borohydride with iodine.
`I_2 + 2NaBH_4 to B_2H_6 + 2NaI + H_2`
Diborane is produced on an industrial scale by the reaction of `BF_3` with sodium hydride.
`2BF_3 + 6NaH overset(450 K)to B_2H_6+6NaF`
Physical properties :
Diborane is a colourless, highly toxic gas with a b.p. of 180 K.
Diborane catches fire spontaneously uponexposure to air.
It burns in oxygen releasing an enormousamount of energy.
Chemical properties :
Boranes are readily hydrolyzed by water to give boric acid .
`B_2H_(6(g)) + 6H_2O_((l)) to 2B(OH)_(3(aq)) + 6H_(2(g))`
Diborane undergoes CLEAVAGE reactions with Lewis bases (L) to give borane adducts, `BH_3 xx L`.
`B_2H_6+2NMe_3 to 2BH_3 . NMe_3`
`B_2H_6+ 2CO to 2BH_3 . CO`
Reaction of ammonia with diborane gives initially `B_2H_6 .2NH_3` which is FORMULATED as `[BH_2(NH_3)_2]^(+) [BH_4]^-`further heating gives borazine, `B_3N_3H_6` known as "inorganic benzene" in view of its ring structure with alternate BH and NH GROUPS.
`2B_2H_6+6NH_3 to 2[BH_2(NH_3)_2]^(+)[BH_4]^(-)oversetDeltato 2B_3N_3H_6+12H_2`

The four terminal hydrogen atoms and the two boron atoms lie in one plane. Above and below this plane, there are two bridging hydrogen atoms.
The four terminal B-H bonds are regular two centre-two electron bonds while the two bridge (B-H-B) bonds are different and can be DESCRIBED in terms of three centre-two electron bonds shown in fig.
Boron also forms a series of hydridoborates, the most important one is the tetrahedral `[BH_4]^-`ion. Tetrahydridoborates of several metals are known. Lithium and sodium tetrahydridoborates, also known as borohydrides, are prepared by the reaction of metal hydrides with `B_2H_6` in diethyl ether.
`2MH+B_2H_6 to 2M^(+) [BH_4]^(-)`where , [M=Li,Na]
Both `LiBH_4` and `NaBH_4` are used as reducing agents in organic synthesis. They are useful starting materials for preparing other metal borohydrides.
Discussion
25.

What is the pH value of human blood ?

Answer»

7.4
8
6.4
8.4

Answer :A
Discussion
26.

Which of the following compounds exhibits geometrical isomerism?

Answer»

2,3-dimethyl 1-2-butene
2,3-dichloro-1-butene
2,3-dichloro-2-butene
1,1-dichloro-1-butene

Solution :`CH_3-undersetoverset(|)(CL)(C ) = undersetoverset(|)(Cl)(C ) - CH_3`
Discussion
27.

Which of following is correct for P_(4) molecule of white phosphorus ?

Answer»

It has 6 lone PAIRS of electrons
It has six P-P single bonds
It has THREE P-P single bonds
It has four lone pairsof electrons

Answer :B::D
Discussion
28.

Which of the following statements is not correct regarding purification of liquids by steam distillation ?

Answer»

Impurities MUST be non-volatile
The liquid must be completely immiscible with WATER
The liquid must POSSES high BOILING point
The liquid must be miscible in water

ANSWER :D
Discussion
29.

What is the state of hybridization of carbon atoms in diamond and graphite?

Answer»

SOLUTION :`SP^(3) ` and `sp^(2)`
Discussion
30.

Torsion strain is the repulsive interaction between

Answer»

ELECTRON cloud of TWO bonds
Electron cloud of two `sigma`-bonds
Electron cloud of two `PI`-bonds
Electron cloud of two `sigma`-bonds on ADJACENT atoms

Answer :A::B::C::D
Discussion
31.

Which of the following orders of ionic radii is correct ?

Answer»

`H^(-)LGT H^(+)gt H`
`NA^(+)gt F^(-)gt O^(2-)`
`Fgt O^(2-)gt Na^(+)`
NONE of these

Discussion
32.

Which of the following statement about buckyball is incorrect ?

Answer»

It is `C_(60)` allotrope of carbon
All the carbon ATOMS are `SP^(3)`-hybridized
It CONTAINS 20 six membredrings and 12 FIVE-membered rings.
Five membered rings are connected both on five and six-membered rings

Solution :Five membered rings are connected only to six membered rings and not to five membered rings.
Discussion
33.

When the positive and negative charge present on carbon ? Give example

Answer»

Solution :If the carbon have three COVALENT bond and ONE vacant orbital then carbon contain (+1) charge e.g. All carbocation `H_(3) overset(+)(C )` means `H - UNDERSET(underset(H)(|))overset(+)(C )-H`
If the carbon have three bond and one non bonding ELECTRON pair then carbon contain (-1) charge. e.g All carbanion `H_(3) bar(C )`: means `H- underset(underset(H)(|))overset(..)( C)-H`
Discussion
34.

The stability of dihalides of Si, Ge, Sn and Pb increases steadily in the sequence,

Answer»

`GeX_(2)ltltSiX_(2)ltltSnX_(2)ltltPbX_(2)`
`SiX_(2)ltltGeX_(2)ltltPbX_(2)ltltSnX_(2)`
`SiX_(2)ltltGeX_(2)ltltSnX_(2)ltltPbX_(2)`
`PbX_(2)ltltSnX_(2)ltltGeX_(2)ltSiX_(2)`

ANSWER :C
Discussion
35.

When hydrogen gas at high pressure and room temperature expands adiabatically to a region of low pressure there is a decreases in temperature Hydrogen gas at room temperature is above its inversion temperature .

Answer»

SOLUTION :HYDROGEN gas at high pressure and room TEMPERATURE expands adiabatically into a REGION of LOW pressure there is a increase in temperature .
Discussion
36.

The standard reduction potential of three metallic cations x,y and z are +0.52,-3.03 and -1.18V respectively .The order of reducing power is:

Answer»

`YgtZgtX`
`XgtYgtX`
`ZGTYGTX`
`ZgtXgtY`

SOLUTION :is the CORRECT ANSWER
Discussion
37.

Which is the structural formula of 4-methyl hex-5-yne-2-one?

Answer»

`CH_(3)-CH_(2)-underset(underset(O)(||))(C )- underset(underset(CH_(3))(|))(C H)-C -= CH`
`CH_(3)- CO - underset(underset(CH_(3))(|))(C H)- CH_(2)- C -=H`
`CH -= C- overset(overset(CH_(3))(|))(CH)-CH_(2)- overset(overset(O)(||))(C )-CH_(3)`
`CH -= - C CH_(2)- underset(underset(CH_(3))(|))(C H)-overset(overset(O)(||))(C )-CH_(3)`

Answer :C
Discussion
38.

Which of the following compounds has zero dipole moment?

Answer»

`BeCl_(2)`
`HCl`
`NH_(3)`
`H_(2)O`

ANSWER :A
Discussion
39.

Which of the following ions is not isoelectronic with O^(2-)

Answer»

`N^(3-)`
`F^-`
`TI^(+)`
`NA^+`

Solution :`Ti^2`has more `e^-` than `O^(-2)`
Discussion
40.

Which of the following statements are correct.

Answer»

Tendency to form complex: `Sc^(+3) gt Y^(+3) gt LA^(+3)`
Most of `LN^(3+)` are coloured.
Ln(II) hydroxides are MAINLY basic in character
lanthanoids RELEASE `H_(2)` on reaction with strong acids.

Answer :A::B::C::D
Discussion
41.

Two gases have densities 0.388g/cc and 0.097gm/cc. If the second gas has the rate of diffusion 5cc/sec, find the rate of duffusion of the first gas.

Answer»


ANSWER :10cc/sec
Discussion
42.

What products are formed when m-xylene is treated with Br_(2) in the presence of FeBr_(3) ?

Answer»




ANSWER :B
Discussion
43.

What is the chemical compositon of zeolite ?

Answer»

Solution :HYDRATED SODIUM ALUMINIUM silicate , `Na_(2), Al_(2), Si_(2)O_(8).xH_(2)O`
Discussion
44.

The RMS velocity of an ideal gas at 300K is 12240 cm/see, then its most probable velocity in cm/sec at the same temperature is

Answer»

10000
11280
1000
12200

Solution :`C_P : BARC : C = 1 : 1 : 128: 1.224 `
`IMPLIES if C = 12240 cm//s ` then `C_p = 10000 cm//s`.
Discussion
45.

Which of the following does not represent the correct resonance struture of carbon monoxide

Answer»

`: C: : : O:`
`:C -=O:`
`:Coverset(LARR)(=)O:`
`:Coverset(RARR)(=)O:`

ANSWER :D
Discussion
46.

Two liquids (A) and (B) can be separated by the method of fractional distillation. The boiling point of liquid (A) is less than boiling point of liquid (B). Which of the liquids do you expect to come out first in the distillate ? Explain.

Answer»

Solution :Fractional distillation is used to SEPARATE the components of a MIXTURE if their boiling points differ by `20^(@)` or less. In this method, a fractionating column is used in between the flask and the condenser. The purpose of the fractionating column is to PROVIDE hurdles for the ascending vapours and to provide large surface area for condensing the high boiling liquid. Consequently, the vapours of the low boiling liquid (A) will move up while those of the high boiling liquid will condense and fall back into the flask. As a result of this FRACTIONATION, liquid A with lower boiling POINT will distil first and liquid B with higher boiling point afterwards.
Discussion
47.

Which of the following is an extensive property ? (a) Volume, (b) Surface tension, (c ) Viscosity , (d) Density.

Answer»

SOLUTION :(a) VOLUME is an EXTENSIVE PROPERTY.
Discussion
48.

Which of the following do not sublime on heating ?

Answer»

`AlF_(3)`
`AlCl_(3)`
`AlBr_(3)`
`AlI_(3)`

Solution :Only `AlCl_(3)` sublimes on HEATING.
Discussion
49.

Which of the following contains maximum number of lone pairs on the central atom?

Answer»

`ClO_(3-)`
`XeF_(4)`
`SF_(4)`
`I_(3)^(-)`

Solution :`1_(3)^(-)`
Discussion
50.

The relative number of atoms of different elements in a compound are as follows : A = 1.33, B = 1 and C = 1.5. The emperical formula of the compound is

Answer»

`A_(2)B_(2)C_(3)`
`ABC`
`A_(8)B_(6)C_(9)`
`A_(3)B_(3)C_(4)`

SOLUTION :`A:B: C`
`(1.33 1 1.5) 6 rArr 8:6:9`
Discussion