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.

Write down the outermostelectronic configuration of alkali metals. How Justify their placement in group 1 of the periodic table ?

Answer»

SOLUTION :All the ELEMNTS of group 1A (alkali metals.) they have same outer electronic configuration .i.e, `ns^(1) ( :. n=no`. Of PRINCIPLE shell.)
Electronic configuration is given below :
Discussion
2.

Which among the following compound behave both as an electrophile as well as nucleophile (a) CH_(2) - CH_(2) (b) CH_(2) = CH - CH_(2) (c ) CH_(3) - oversetoverset(O)("||")C-CH_(3) (d) CH_(3) - oversetoverset(O)("||")C-Cl

Answer»

Only a
a and B
C and d
b,c and d

ANSWER :C
Discussion
3.

Write Lewis dot symbols for atom of the following elements : Mg, Na , B, O, N, Br

Answer»

SOLUTION :`""_(12) MG = 2, 8, 2therefore `Lewis symbol =` overset(cdot )Mg*.""_(11) Na = 2,8, 1 therefore ` Lewis symbol = `overset(cdot )Na `
`._(5)N = 2, 5 therefore ` Lewis symbol= `*overset(cdot)(B )* ."" _(8)O = 2, 6therefore `Lewis symbol = `:overset(cdotcdot)(O):`
` _(7)N = 2, 5therefore `Lewissymbol= `:overset(cdotcdot)underset(cdot)(N):""_(35)Br = 2 , 8 , 28 , 7 therefore ` Lewis symbol=`:overset(cdotcdot)underset(cdotcdot )(Br):`
Discussion
4.

The shape of acetylene molecule is …………….

Answer»

SOLUTION :CYLINDRICAL
Discussion
5.

Which of the following are basic

Answer»

`B_(2)O_(3)`
`Pl_(2)O_(3)`
`In_(2)O_(3)`
`Al_(2)O_(3)`

SOLUTION :`Tl_(2)O_(3), In_(2)O_(3)` are more basic because of its SIZE.
Discussion
6.

What do the following abbreviations stand for ? (i) dL (ii) dm (iii) mu m (d) nL

Answer»


ANSWER :(a) DECILITRE (B) decimetre (C) MICROMETRE (d) nanolitre
Discussion
7.

Which of the following organohalogen compounds when heated with alcoholic potassium hydroxide does not undergo dehydrohalogenation reaction ?

Answer»

SECONDARY butyl chloride
ISOPROPYL chloride
Neopentyl chloride
Isobutyl chloride

Solution :`underset"Neopentyl bromide"(CH_3-underset(CH_3)underset(|betaalpha)oversetoverset(CH_3)|C-CH_2Br)OVERSET(KOH(alc.),Delta)to "No" beta`- HYDROGEN, no dehydrohalogenation reaction
Discussion
8.

What happens when KO_(2) reacts with water ? Write the balanced chemical equation for the reactions

Answer»

SOLUTION :`2 KO_(2) + 2H_(2)O to 2 KOH+ H_(2)O_(2) + O_(2) or 4KO_(2) + 2H_(2)O to 4 KOH + 3O_(2)`.
Discussion
9.

What are alkali metals?

Answer»

Solution :1 st GROUP ELEMENTS of periodic table i.e.,lithium, sodium, POTASSIUM, rubidium and CAESIUM are called ALKALI metals.
Discussion
10.

Uses of sodium metal is....

Answer»

as a REDUCING agent
in NUCLEAR reactor
in LESION test
All of above

Answer :D
Discussion
11.

What is the value of Avogadro's Number ?

Answer»


ANSWER :`6.022 XX 10^(23)`
Discussion
12.

The tautomeric pairs are

Answer»

`Me_(2)C=NOH and Me_(2)CH-underset(o+)N=O`
`CH_(2)=CH-NHCH_(3) and CH_(3)-CH=N-CH_(3)`

`CH_(2)=CH-underset(OH)underset(|)CH-CH_(3) and CH_(3)-CH_(2)-underset(O)underset(||)O-CH_(3)`

SOLUTION :(A,B) `{:("NITROSO" hArr "oxime (Tautomer)"),("lmine" hArr "enamine (Tautomer)"):}`
Discussion
13.

What is the maximinn number of orbitals that can be identified with the following quantum number.

Answer»

1
2
3
4

Answer :A
Discussion
14.

Thesize of Cl^(-)=1.81ÅandCl=0.99Å.Explain.

Answer»

Solution :`C1-1s^(2)2s^(2)2p^(6)3s^(2)3p^(5),C1^(-)-1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)`
GENERALLY anions are larger than their parent atom
`C1^(-)`had 18 electrons andC1 has 17 electrons . Thelater experiences an greater effective INWARD PULL by the nucleus.
This decreases the SIZE of C1 atom when compared to `C1^(-)` ion.
Discussion
15.

Write structures for each of the following compounds. Why are the given names incorrect ? Write correct IUPAC names : (i)2-Ethylpentane , (ii)5-Ethyl-3-methylheptane.

Answer»

SOLUTION :`(i)CH_3-underset("".^2CH_2overset1CH_3)underset(|)overset3(CH)-overset4CH_2overset5CH_2overset6CH_3`
The longest chain here contains six carbon atoms and not five . Therefore, the correct name is 2-methylhexane.
(ii)`overset7CH_3-overset6CH_2-undersetunderset(CH_3)|overset5CH-overset4CH_2-undersetunderset(""CH-CH_3)|overset3(CH)-overset2CH_2-overset1CH_3`
Since 'e' COMES before 'm' in ALPHABETICAL order , therefore , NUMBERING must be done from right to left. Therefore, the correct name is 3-ethyl-5-methylheptane.
Discussion
16.

Which one of the following characteristics is not correct for physical adsorption?

Answer»

ADSORPTION on solids is reversible
Adsorption increases with increase in temperature
Adsorption is spontaneous
Both enthalpy and entropy of adsorption are negative.

Solution :In PHYSICAL adsorption, the extent of adsorption DECREASE with increase in temperature.
Discussion
17.

Which type of hydrides are generally non-stoichiometric in nature?

Answer»

Metallic hydride
Covalent HYDRIDES
 IONIC hydride
Saline hydride

ANSWER :a
Discussion
18.

What is the nuclear radius of an atom whose mass number is 125 ?

Answer»

SOLUTION :Nuclear radius, `r = R_(0) A^(1//3) " where " R_(0) = 1.4 xx10^(-15)m`, A = MASS NUMBER
`:. "" r = (1.4 XX 10^(-15)m) xx (125)^(1//3) = 1.4 xx 10^(-15) xx 5m = 7.0 xx 10^(-15)m`
Discussion
19.

The value of n,lm and s of 8^(th) electron in an oxygen atom are respectively…………

Answer»

SOLUTION :2,1,+1,-1/2
Discussion
20.

Which is least stable?

Answer»

`.CH_(3)`
`.CH_(2)- CH_(3)`
`CH_(3) - OVERSET(.)CH-CH_(3)`
`CH_(3) - underset(underset(CH_(3))(|))overset(.)CH- CH_(3)`

Answer :A
Discussion
21.

When Sn^(2+) changes to Sn^(4+) in a reaction,then "_____________".

Answer»

It is an OXIDATION as `SN^(2+)` LOSES TWO electrons
it is an oxidation as `Sn^(2+)` gains two electrons
it is a reduction as `Sn^(2+)` loses two protons
it is a reduction as `Sn^(2+)` gains two protons

Answer :A
Discussion
22.

The treatment of CH_3MgX with CH_3C -= C-H produces

Answer»

`CH_4`
`CH_3-CH=CH_2`
`CH_3C-=C-CH_3`
`CH_3-oversetoversetH|C=oversetoversetH|C-CH_3`

SOLUTION :`CH_3C-=C-H + CH_3MgX to CH_3C -= CMgX + CH_4`
Discussion
23.

Which of the following compounds does not react with acetyl chloride ?

Answer»

Methylamine
Dimethylamine
Aniline
Trimethylamine

Answer :D
Discussion
24.

Which of the following reaction produces hydrogen

Answer»

`MG+H_2O`
`BaO_2 + HCL`
`H_2S_4O_8 + H_2O`
`Na_2O_2 + 2HCL`

Solution :`Mg+2H_2O to Mg(OH)_2 + H_2 UARR`
Discussion
25.

Which of the following behaves as a saturated compound?

Answer»

`C_2H_4`
` C_2H_2`
`C_3H_6`
`C_6H_6`

ANSWER :D
Discussion
26.

The size of colloidal particle is in between

Answer»

`10^(-7)-10^(-3) cm`
`10^(-9)-10^(-11) cm`
`10^(-5)-10^(-7) cm`
`10^(-2)-10^(-3) cm`

Answer :C
Discussion
27.

What is responsible for the blue colour of the solution of alkali metali in liquid ammonia? Give chemical equation also.

Answer»

Solution :The Solvated electron, `[e(NH_(3))]^(-)` or ammoniated electron is responsible for bios COLOUR of alkali metal solution in `NH_(3)`. It absorbs light from VISIBLE region and radiates COMPLEMENTARY colour. (in the equation am = amnioniated)
`Na^(+) (am) + e^(-) (am) + NH_(2) (I) to NaNH_(2) (am) + (1)/(2) H_(2) (g)`
Discussion
28.

Write the formulae of the first 5 members of homologous series starting with the underlined CH_2=CH_2

Answer»


ANSWER :`CH_3CH=CH2, CH_3CH_2CH=CH_2, CH_3CH_2CH_2CH=CH_2, CH_3-CH_2-CH_2-CH_2-CH=CH_2`
Discussion
29.

Write isotopes of alkaline C_(4)H_(8) and give one examples of it.

Answer»

Solution :(a) Position ISOMERS :
`CH_(3) - CH_(2) -C -=CH`
`CH_(3)-C-=C-CH_(3)`
(b) CHAIN isomers : There is no chain isomers of `C_(4)H_(8)`
(c) FUNCTIONAL group isomers :
`underset("But-1,2-diene")(H_(2)=C=CH-CH_(3))`
`underset("But-1,3-diene")(CH_(2)=CH-CH=CH_(2))`
(d) Cyclic isomers :
Discussion
30.

Weight percentage of meta is 0.033 calK^(-1) ,Calculate the valency of metal.

Answer»


ANSWER :2
Discussion
31.

What is the oxidation number of sulphur in the following molecules/ ions H_2SO_4

Answer»

Solution :In `H_2SO_4` LET X,+1 ,-2 be oxidation NUMBER of S, H and O
Let ON Be

i.e., `(+1 times 2)+ (x times 1)+(-2 times 4)=0`
`implies (1 times 2)+x+ (-2 times 4) =0 , 2+ x-8=0, x=+6`
Oxidation number of S in `H_2SO_4`is +6.
Discussion
32.

Which solid is most soluble in water at 25^(@)C?

Answer»

`AgNO_(3)`
`CaCO_(3)`
`PbO`
`ZNS`

ANSWER :A
Discussion
33.

Which liquid interact each other ?

Answer»

WATER - Oil
`H_(2)O` - ETHANOL
Water - Petrol
Water Kerosene

Answer :B
Discussion
34.

Which is least stable ?

Answer»

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

ANSWER :A
Discussion
35.

Which of the following statements concerning atomic size is correct?

Answer»

Atoic size DECREASES down a group
Atomic size decreases ALONG a PERIOD
Radius of cation is more than that of the atom
Radius of anion is LESS than that of the atom

ANSWER :B
Discussion
36.

When 5.0 g of a metal is strongly heated, 9.44g of its oxide is obtained. Then the equivalent mass of the metal is ?

Answer»

12
9
32.5
31.75

Solution :EQUIVALENT weight of metal `= ("WT of metal")/(" wt of oxygen") XX8`
`=(5)/(4.44) xx 8 =(40)/(4.44) =9`
Discussion
37.

Which is not suitable for atomic radius?

Answer»

In each period as GOING from L.H.S. to R.H.S. is decreases.
Increases from top to bottom.
Increases with INCREASE in POSITIVE CHARGE on atom.
Increases with increase in principle quantum number.

Solution : Increases with increase in positive charge on atom.
Discussion
38.

Whatis atomicnumberand number ofelectronin I and II protonpresent in hydrogenand sodium atomrespectively

Answer»

Solution :ATOMICNUMBER (Z ) =NUMBEROF protonsin nucleus
ATOMIC numberof hydrogen is I andatomicnumberof sodium is 11
In hydrogen 1 protonand sodium 11 proton
Discussion
39.

The species present in solution when CO_(2) is dissolved in waterare :

Answer»

`CO_(2), H_(2) CO_(3), HCO_(3)^(-), CO_(3)^(2-)`
`H_(2)CO_(3)^(2-), CO_(3)^(2-)`
`CO_(3)^(2-), HClO_(3)^(-)`
`CO_(2), H_(2)CO_(3)`

SOLUTION :`CO_(2)+H_(2)O rarr H_(2)CO_(3) rarr H^(+) + underset( H^(3) + CO_(3)^(-2))underset(darr)(HCO_(3)^(-))`
Discussion
40.

What is the covalence of nitrogen in N_(2)O_(5) ?

Answer»

SOLUTION :Covalency depends upon the number of SHARED pairs of electrons. Now in `N_(2)O_(5)`, each NITROGEN ATOM has FOUR shared pairs of electrons as shown : Therefore, the covalency of N in `N_(2)O_(5)` is 4.
Discussion
41.

Which carboxylic acid(s) gives acetaldehyde on strong heating in presence of catalyst

Answer»

`(-)Ph-UNDERSET(CH_(3))underset(|)CH-NH_(2)`
`(+-)Ph-underset(CH_(3))underset(|)CH_(3)-NH_(2)`
`Me-NH_(2)`
`Me_(2)CHNHMe`

Solution :`(-)Ph-underset(CH_(3))underset(|)CH-NH_(2)`
Discussion
42.

Viscosity of ethanol is 12.0 millipoise. Viscosity of ethanol in S.I system is equal to

Answer»

`1.2`
`1.2 xx 10^(-3)`
`1.2 xx 10^(-2)`
`1.2 xx 10^(-1)`

Solution :12 m poise = `12 xx 10^(-3) ` poise.
1 poise = CGS unit = `(1 GM)/(Cm - S) = (10^(-3)KG)/(10^(-2) m - s)`
`= 0.1 SI UNITS = 12 xx 10^(-3) ` poise
` = 12 xx 10^(-3) xx 0.1 kg//m-s = 1.2 xx 10^(-3)`.
Discussion
43.

Which of the following compounds is the reactant in Rosenmund's reduction ?

Answer»

`CH_(3)CO_(2)H`
`CH_(3)CHO`
`CH_(3)CH_(2)CL`
`CH_(3)COCL`

Solution :Refer to comprehensive review
Discussion
44.

Which of the given compound is optically active?

Answer»




SOLUTION :N//A
Discussion
45.

Which of the following is correct comparison for the above effect? Deuterium Kinetic isotopic effect=("Rate of homolytic clevage of C-H bond by Cl")/("Rate of homolytic clevage of C-D bond by Cl")

Answer»

`GT1`
`LT1`
`=1`
cannot be predicted.

Answer :A
Discussion
46.

When phenol is treated with excess bromine water, it gives

Answer»

m-Bromophenol
b and p-Bromophenol
2,4-Dibromophenol
2,4,6-Tribromophenol

Answer :D
Discussion
47.

What Is bond order ? Explain by example.

Answer»

Solution :Bond order according to Lewis : The bond order is given by the number of bonds (SHARED electron pair) between the two atoms in a molecule.
e.g. : Bond order in `H_(2), F_(2), Cl_(2)`, HCl is one. In `O_(2) ` bond order two and in`N_(2) ` three because shared electron pairs between two atoms is respectively 2 and 3.
According to MO theory bond order : `(1)/(2) (N_(b) - N_(a)) ` where , `N_(b)`= Total no. of boding `e^(-)` of BMO `N_(a)` = Total no. of anti BONDING `e^(-)` of ABMO
Bond order : the difference of electron in MO and ABMO orbitals divided by 2 is called Bond order.
e.e. :Bond order in`H_(2) = (1)/(2) (N_(b) - N_(a))`
`= (1)/(2)( 2 - 0) = 1 `
= `(1)/(2)(2 - 0) = 1 `
Bond order in `F_(2) , Cl_(2) , Br_(2) =(1)/(2) (N_(b) - N_(a))`
= `(1)/(2) (10 - 8) = 1 `
Bond order BO in `O_(2) = (1)/(2) (10 - 6 ) = 2 `
Bond order BO in `N_(2) = (1)/(2) = (10 - 4) = 3`
Discussion
48.

Write the uses of freon.

Answer»

SOLUTION :(i) Freon gas is USED in refrigerators, air conditioners and in the production of plastic foam. (II) It is used in electronic industry for CLEANING computer parts.
Discussion
49.

Which of the following groups has the highest inductive effect?

Answer»

`-CH_(3)`
`CH_(3)CH_(2^(-))`
`(CH_(3))_(2)CH-`
`(CH_(3))_(3)C-`

Solution :Among the FOLLOWING carbane ions the HIGHEST I EFFECT is `3^(@)`-carbaneion DUE to less stability
Discussion
50.

Writenote on resonance of benzene

Answer»

Solution :(i) thephenomenon in which two or morestructures can be written for a substancewithhas identical POSITIONOF atomsis calledresonance
(II)Theactualstructureof the molecule is saidto bea resonancehybrid of thevariouspossiblealtemativestructure.

(iii)isbenzeneKekulestructure 1 and iirepresentedteh resonancestructureand structureiii isthe resonancehybridof structuresii and i
(iv)the structurei and iiexistonlyin theory.theactualstructuralof BENZENEIS thehythaneof twohypotheticalresomancestructure.
Discussion