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 the pH of a buffer solution prepared by dissolving 0.1 mole of sodium acetate and 0.2 mole of acetic acid in enough water to make a dm^(3) of solution? (K_(a) of acetic acid = 1.8xx10^(-5)).

Answer»

Solution :`pK_(a)=-logK_(a)`
= `-log1.8xx10^(-5)`
= -(5.2553)
= 4.7447
`pH=pK_(a)+"LOG"(["salt"])/(["ACID"])`
= `4.74+"log"0.1/0.2`
= `474+log0.5`
= 4.74 - 0.3010
= 4.44
Discussion
2.

Under whatcondition DeltaHbecomesequal to DeltaU?

Answer»

Solution :`DeltaH = DeltaU` during a process which is carried out in a CLOSED vessel `( DeltaU = 0 )` or number of moles of gaseous products `=` number of moles of gaseous REACTANTS or the reaction does not involve any gaseous or PRODUCT.
Discussion
3.

What is the reason behind the blue colouration of alkali metals with liquid ammonia? M+(x+y)NH_(3)to[M(NH_(3))_(x)]^(+)+[e(NH_(3))_(y)]^(-)

Answer»

Solution :The blue COLOUR of the solution is due to the ammoniated ELECTRON which absorbs energy in the visible REGION of light and thus imparts blue colour to the solution. The solutions are paramagnetic and on standing slowly liberate hydrogen RESULTING in the formation of amide. In concentrated solution, the blue colour changes to bronze colour and become diamagnetic.
Discussion
4.

The shape of CH_4, SO_4^(2-), PO_4^(-3) is

Answer»

Trigonal PLANAR
ANGULAR
Tetrahedral
Trigonal bipyramidal

Solution :All of them have total four bond pairs with zero lp. Hence tetrahedral in SHAPE.
Discussion
5.

Which of the following is not an intensive property?

Answer»

DENSITY
MOLARITY
Molality
Mole

ANSWER :D
Discussion
6.

Which of the following IUPAC name of the molecule is not correct?

Answer»

`UNDERSET("4-methylpent-2-ene")(CH_(2)=CH-CH_(2)-underset(underset(CH_(3))(|))(CH)-CH_(3))`
`underset("Pent-4-ene-2-amine")(CH_(2)=CH-CH_(2) underset(underset(NH_(2))(|))(CH)-CH_(3))`
`underset("Pent-1-ene-4-ol")(CH_(2)=CH-CH_(2)- underset(underset(OH)(|))(CH)-CH_(3))`
`underset("Pent-4-ene-2-one")(CH_(2)=CH-CH_(2)-underset(underset(O)(||))(C )-CH_(3))`

ANSWER :C
Discussion
7.

Vapour Pressure is depend upon ?

Answer»

SOLUTION :(i) TEMPERATURE(II) LIQUID
Discussion
8.

The SI unit of temperature is ..........

Answer»

`""^(@)C`
`""^(@)F`
K
all of the above

Answer :C
Discussion
9.

Which zone is called ozonosphere ?

Answer»

SOLUTION :STRATOSPHERE
Discussion
10.

The uncertainity in momentum of an electron is 1 xx 10^(-5) kg.m//s. The uncertainity in its position will be (h = 6.62 xx 10^(-34)kg.m//s)

Answer»

`1.05xx10^(-28)m`
`1.05xx10^(-26)m`
`5.27xx10^(-30)m`
`5.27xx10^(-28)m`

ANSWER :C
Discussion
11.

The stability order of alkene in following compounds is :

Answer»

`IltIIltIIIltIV`
`IIltIltIIIltIV`
`IIltIIIltIltIV`
`IIltIVltIltIII`

ANSWER :A
Discussion
12.

Which is expected to be more stable, O_2 NCH_2CH_2O or CH_3CH_2O and why?

Answer»


Answer :`O_2N-CH_2-CH_2-O^-` is more STABLE because `-NO_2` group being ELECTRON withdrawing (-I) disperses the NEGATIVE charge on oxygen ATOM. In the other +1 effect of ALKYL group intensifies the negative charge (unstable).
Discussion
13.

Which of the following is not the consequence of global warming?

Answer»

INCREASE in AVERAGE TEMPERATURE of Earth.
Melting of HIMALAYAN glaciers
Rise in SEA level
Eutrophication

Answer :D
Discussion
14.

The reagent which gives the same reduction product with propionaldehyde and acetone is

Answer»

`LiAIH_(4)`
`Na-Hg//H_(2)O`
`Ni//H_(2)`
`Zn-Hg//Conc.HCl`

Solution :Clemmenson 's (or) WOLF - kishner REDUCTION
Discussion
15.

Which of the following are examples of Birch reduction ?

Answer»




`CH_3C -= C CH_3 underset(LIQ. NH_3)OVERSET(Na)to CH_3CH= CHCH_3 `

Solution :A, C are perfect examples of BIRCH reduction, because electron donating groups always appear on one side of double bonded .C., but electron with drawing groups are not on the .C. INVOLVED in a double BOND.
Discussion
16.

When 3, 3-dimethylbutan-2-ol is heated with conc.H_(2)SO_(4), then main product formed is

Answer»

3, 3-Dimethylbutene-1
2, 3-Dimethylbutene-2
2, 3-Dimethylbutene-1
cis and trans ISOMERS of the product OBTAINED in (C).

SOLUTION :
Discussion
17.

What are the values of n, l, m and s for 3p_(x) electron ?

Answer»

<P>3,2,1,0
`3, 1, -1, + ½`
`3, 2, +1, -½`
`3,0,0, +½`

Solution :`3p_(X)` electron , n = 3 (main SHELL)
for `p_(x)` orbital, `L = 1, m = -1, s = ½`
Discussion
18.

Write name of Cr_(2)O_(3) according to stock notation.

Answer»

SOLUTION :CHROMIUM (III) OXIDE.
Discussion
19.

Which of the following relativelymore strong acid in aqueous solutions?

Answer»

`HClO_4`
`H_2SO_4`
`Hl`
All are EQUALY STRONG

SOLUTION :DUE to levelling effect
Discussion
20.

Which of the following is not the use of alkali metals .

Answer»

White metal , an ALLOY of lithium and lead is used in manufacture of bearing for motore engines .
Sodium-lead alloy is used in the preparation tetraethyl lead and ANTI knocking agent .
POTTASIUM chloride is used as fertilizer
The alkali metals used in photoelectric cells are lithium and sodium .

Answer :D
Discussion
21.

Which among the following is a redox reaction ?

Answer»

`Ca(OH)_(2) + 2HClrarr CaCl_(2) + 2H_(2)O`
`BaCl_(2) + MgSO_(4) rarr BaSO_(4) + MgCl_(2)`
`2S_(2)O_(7)^(2-) + 2H_(2)O rarr 4SO_(4)^(2-) + 4H^(+)`
`Cu_(2)S+ 2FeO rarr 2Cu + 2Fe + SO_(2)`

Answer :D
Discussion
22.

Which of the following is a set of reducing agents ?

Answer»

`HNO_(3),Fe^(2+),f_(2)`
`F^(-),cI^(-),MnO_(4)^(-)`
`I^(-),Na,Fe^(2+)`
`Cr_(2)O_(7)^(2-),crO_(4)^(2-),Na`

Solution :Since CI in `CIO^(-)` has an O.N of +1 which is higherthan its lowest O.N of -1 and lower than its highest O.N of +5 therefore `CIO^(-)` can act as an oxidising as well as reducing agent
Discussion
23.

What is the IUPAC name of

Answer»

2, 3-dimethyl, 7-bromooctane<BR>2-bromo-5, 6-dimethyloctane
2-bromo-6, 7-dimethyloctane
1-bromo-5, 6-dimethylheptane

Solution :`underset("2-bromo-6, 7-dimethyloctane")(C OVERSET(8)(H_(3)) - underset(underset(H)(|))overset(overset(H_(3)C)(7|))(C )- underset(underset(CH_(3))(|))overset(overset(H)(-6|))(C )- overset(5)(C )H_(2)- overset(4)(C )H_(2)- overset(3)(C )H_(2)- underset(underset(Br)(|))overset(2)(C )H- overset(1)(C )H_(3))`
Discussion
24.

The threshold energy for photoelectric emission of electrons from a metal is 3.056 xx 10^(-15) joule. If light of 4000 Å wavelength is used, will the electrons be efected or not ? (h = 6.63 xx 10^(-34) Joule sec)

Answer»


Solution :ELECTRONS will be ejected only if the ENERGY of incident LIGHT is greater than the threshold energy.
Energy of the incident light `= hv = h (C)/(lamda) = (6.63 xx 10^(-34) xx 3 xx 10^(8))/(4000 xx 10^(-10)) J = 4.97 xx 10^(-19) J`
Thus is less than threshold energy
Discussion
25.

What is meant by point defect in crystals ?

Answer»

Solution :The defect caused by MISSING or DISPLACEMENT of ATOMS or ions in a CRYSTAL is called point defect.
Discussion
26.

The screening effect of d-electrons is

Answer»

<P>EQUAL to p - ELECTRONS
much more than p - electrons
same as F - electrons
less than p - electrons

Answer :D
Discussion
27.

X ml of H_(2) gas effuses through a hole in a container in 5 seconds. The time taken for the effusion of the same volume of the gas specified below under identical conditions is

Answer»

10 seconds : He
20 seconds : `O_(2)`
25 seconds : CO
55 seconds : `CO_(2)`

Solution :`(r_(H_(2)))/(r_(X))=sqrt((M_(X))/(M_(H_(2))))" or " (X//5)/(X//t)=sqrt((M_(X))/(2))`
or `(t)/(5)=sqrt((M_(X))/(2))`
The equaloty HOLDS GOOD only for (b).
Discussion
28.

The temperature of the system, decreases in an_________.

Answer»

ISOTHERMAL EXPANSION
Isothermal COMPRESSION
ADIABATIC expansion
adiabatic compression

Answer :C
Discussion
29.

Which solute has the greatest solubility (in mol/L) in water at 25^(@)C and 1 atm?

Answer»

`CH_(4)`
`NH_(3)`
`AGCI`
`CaSO_(4)`

Answer :B
Discussion
30.

Which orbitals are involved in bond overlapping of each carbon in benzene ?

Answer»

Solution :(i) C-C sigma BOND is formed by overlapping of `SP^(2)-sp^(2)` hybridized orbital of two CARBON atoms.
(ii) The sigma bond is formed between C-H by overlapping of `sp^(2)` hybridized orbital of C and 1S orbital of H and form a bond between C and H.
(iii) `pi`-bond is formed by overlapping of 2p-2p ORBITALS of each two carbon.
Discussion
31.

What is the distance between Na^+ and Cl^- in a NaCl crystal if its density is 2.165 "g cm"^(-3) ?NaCl crystallises in the fcc lattice

Answer»


ANSWER :281 PM
Discussion
32.

Valence electrons in the atom of elements A is 4 and in the element B is 2. Most probale compund from A and B is

Answer»

`AB_(3)`
`AB_(2)`
`A_(2)B_(3)`
`A_(2)B`

ANSWER :B
Discussion
33.

Which contain more strong H-bond in the followi!)g pair ? (i) H_(2)O and H_(2)S (ii) NH_(3) and PH_(3) (iii) HF and HCl.

Answer»

SOLUTION :(i) `H_(2)O` (ii) `NH_(3) ` (iii) HF
Discussion
34.

Which one of the following is correct order? (A) T_(2) gt D_(2) gt H_(2) (order of BP) (B) T_(2) gt D_(2) gt H_(2) (order of BE) (C) T_(2)=D_(2)=H_(2) (order of BL) (D) T_(2) lt D_(2) lt H_(2) (order of reactivity with Cl_(2))

Answer»

A, B & C
A, B, C & D
A, B
D, B & C

Solution :All options are CORRECT.
Discussion
35.

The stability of hydrophobic sol is due to

Answer»

SOLVATION of COLLOIDAL particles
the CHARGE on the colloidal particles
the SIZE of the particles
None of the above.

Answer :B
Discussion
36.

Write reaction for autoprotolysis of water. How is ionic product of water related to ionization constant of water ? Derive the relationship.

Answer»

SOLUTION :Autoprotolysis of `H_(2)O` TAKES place as :
`{:(H_(2)O+H_(2)O,HARR,H_(3)O^(+)+OH^(-)),(""H_(2)O,hArr,H^(+)+OH^(-)):}`
For IONIZATION of `H_(2)O`,
`K_(i)=([H^(+)][OH^(-)])/([H_(2)O])=(K_(w))/([H_(2)O])=(K_(w))/(55.55 "mol" L^(-1)) or K_(w)=K_(i)xx55.55`.
Discussion
37.

The sulphate of an element contains 42.2% element. The equivalent mass would be

Answer»

17
35
51
68

Answer :B
Discussion
38.

Which of the following statement about solution of alkali metals in liquid ammonia is correct

Answer»

The solution have strong OXIDIZING properties
Both the dilute solution as well as concentrated solution are PARAMAGNETIC in nature
Both the dilute solution as well as concentrated solution are paramagnetic in nature
Charge transfer is the responsible for the colour of the solution

Solution :All are worong the soltion has strongreducingnatureand colured due ot ammoniated ELECTRON
Discussion
39.

Which of the following is strong reducing agent ?

Answer»

`Al_(2)O_(3)`
`BF_(3)`
`LiAlH_(4)`
`AlCl_(3)`

ANSWER :C
Discussion
40.

What is the ratio of number of molecules, if the mass ratio of N_(2) and O_(2) is 4:1?

Answer»

SOLUTION :Ratio of molecules of `N_(2) and O_(2)=`
Ratio of NUMBER MOLES of `N_(2) and O_(2)=(4)/(28):1/(32)`
`=1/7 : 1/(32)=32:7`
Discussion
41.

Which of the following particle having same kinetic energy, would have the maximum de-Broglie wave length

Answer»

`ALPHA` - particle
proton
`BETA`- particle
Neutron

ANSWER :C
Discussion
42.

Write the following as net ionic equations and designate the nucleophile, substrate, and leaving group in each base.

Answer»

SOLUTION :the net ionic equations are as FOLLOWS for (a) and (B) and there is no abbreviated equation possible for (c ). Nucleohiles, substrates and leaving groups are labeled ACCORDINGLY.
Discussion
43.

Which of the following groups shows negative inductive effect?

Answer»

`-COO^-`
`-COOH`
`RS^-`
`-CH_3`

Solution :More ELECTRONEGATIVE GROUP attracts ELECTRONS.
Discussion
44.

What is meant by isoelectronic species ?

Answer»

Solution :Isoelectronic SPECIES are atoms, INOS or molecules having same number of ELECTRONS.
Discussion
45.

What is (X) and (Y) in the above reaction?

Answer»

`RCH_(2)CH_(2)CHO,RCH_(2)CH_(2)CH_(2)OH`
`RCH_(2)CH_(2)CHO,RCH_(2)CH_(2)OH`
`CH_(3)CH_(2)CHO,CH_(3)CH_(3)OH`
`CH_(3)CH_(2)CH_(2)CHO,CH_(3)CH_(2)CH_(2)OH`

ANSWER :A
Discussion
46.

Which of the following groups cannot participate in resosnace with benzene ring ?

Answer»

`-COCL`
`-Noverset(OPLUS)(H_3)`
`-Coverset(oplus)(H_2)`
`-OVERSET(CH_3)overset(|)O^(+)-H`

SOLUTION :
Discussion
47.

Which of thefollowingspecieshas thelargestand thesmallest size ? Mg^(2+) ,Al,Al^(3+)

Answer»

Solution :(i) Mgand A1belongto thethirdperiod.Acrossa periodatomicradiidecreasedue toincreases nuclear charge . Thereforeatomicsizeof ALIS smaller thanthat of Mg.
(ii)Further cations are smaller thantheir parentatoms. Therefore `Mg^(2+)` si smallerthan Mg and `Al^(3+)` issmallerthan Al.
(III) `Mg^(2+)` and `Al^(3+)` are isoelectronicions. AMONG isoelectronicions, higher the + vechargesmallerthesize. Thereforeionicradiusof `Al^(3+)` is smallerthan thatof `Mg^(2+)`
Fromthe abovediscussionsit followsthat MGHAS thelargestwhile`Al^(3+)` has thesmallestsize.
Discussion
48.

Which one of the following is not a crystalline hydrate?

Answer»

 `CH_(4).20H_(2)O`
 `Na_(2)CO_(3).10H_(2)O`
 `CuSO_(4).5H_(2)O`
`FeSO_(4).7H_(2)O`

ANSWER :a
Discussion
49.

Which of the following statement is false?

Answer»

`CA^(2+)` ions are not important in maintaining the regular beating of the heart
`Mg^(2+)` ion areimportant in the green PARTS of the PLANTS
`Mg^(2+)` ions form a complex with ATP
`Ca^(2+)` ions are important in blood clotting

Answer :A
Discussion
50.

Which of the following alkaline earth metal is cofactor of enzyme to utilise ATP in phosphate transfer ?

Answer»

Ca
Mg
Sr
Ra

Answer :B
Discussion