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.

The valence electron configuration of an element with atomic number 23 is

Answer»

`3D^(5)`
`3d^(3) 4S^(2)`
`3d^(2) 4s^(1) 4p^(1)`
`3d^(2)4s^(2) 4p^(1)`

Answer :B
Discussion
2.

Which does not show substituion in benzene ring?

Answer»

`CIDO_(3)H`
`"Conc." H_(2)SO_(4)" on HEATING"`
Conc. HCI
`CH_(3)CI//AICI_(3)`

Answer :c
Discussion
3.

What changes observed when gas is heated ?

Answer»

Solution :When we heated GAS, SPEED of molecules and kinetic energy increases. Pressure increases with increases of AVERAGE speed of kinetic energy increases it will collide with wall of CONTAINER.
Discussion
4.

Which of the following pairs of metals is purified by Van Arkel method ?

Answer»

NI and Fe
Ga and In
Zr and Ti
Ag and Au

Solution :N//A
Discussion
5.

Which of the following expressions represents the electron probability function (D) ?

Answer»

`4pi r dr PSHI^(2)`
`4pi r^(2) dr PSI`
`4pi r^(2) dr Psi^(2)`
`4pi r dr Psi`

ANSWER :C
Discussion
6.

Which of the following alkyl halides is not suitable for Corey-House synthesis of alkanes?

Answer»

`CH_3Br`
`C_2H_5I`
`CH_3CH_2CH_2I`
`(CH_3)_3CBr`

SOLUTION :Reactivity of alkyl HALIDES towards Gilman REAGENT (`R_2CuLi`) decreases in the ORDER. i.e., `1^(@) gt 2^(@) gt 3^(@)`
Discussion
7.

Which of the following have been arranged in decreasing order of oxidation number of sulphur?

Answer»

`Na_(2)S_(4)O_(6)gtH_(2)S_(2)O_(7)gtNa_(2)S_(2)O_(3)gtS_(8)`
`H_(2)SO_(4)gtS_(23)H_(2)SgtH_(2)S_(2)O_(8)`
`SO_(2)^(+)gtSO_(45)^(2-)gtSO_(3)^(2-)gtHSO_(4)^(-)`
`H_(2)SO_(5)hyH_(2)SO_(3)gtSCI_(2)gtH_(2)S`

ANSWER :d
Discussion
8.

Write redox reaction between fluorine and water.

Answer»

Solution :`F_(2)` is a STRONG oxidising AGENT. It oxidises `H_(2)O` to either `O_(2)` or `O_(3)`
`2F_(2)(g) + 2H_(2)O(L) to O_(2) (g) + 4H^(+) (AQ) + 4F^(-) (aq)`
`3F_(2)(g) + 3H_(2)O(l) to O_(3)(g) + 6H^(+) (aq) + 6F^(-)(aq)`
Discussion
9.

Which cannot be oxidised by H_(2)O_(2)?

Answer»

`Na_(2)SO_(3)`
PBS
KI
`O_(3)`

Solution :`Na_(2)SO_(3)` is oxidised by `H_(2)O_(2)" to "Na_(2)SO_(4).PbS` is oxidised by `H_(2)O_(2)" to "PbSO_(4).KI` is oxidised by `H_(2)O_(2)" to "I_(2)O_(3)` cannot be oxidised by `H_(2)O_(2)` but it is reduced to `O_(2)" by "H_(2)O_(2)`.
`H_(2)O_(2)+O_(3) RARR H_(2)O+2O_(2)`
Discussion
10.

Which of the following exponential equation of DeltaG^@= - RT lnK ?

Answer»

`K=e^(DELTAG//RT)`
`K=e^(DeltaG^@//RT)`
`K=e^(-DeltaG^@//RT)`
`K=e^(-DeltaG//RT)`

ANSWER :C
Discussion
11.

What is the net charge on ferrous ion ?

Answer»

`+2`
`+3`
`+4`
`+5`

ANSWER :A
Discussion
12.

Urine normally has a pH of 6.0 . A patient eliminates 1.3 litres of uring per day . How many moles of H^(+) ions does he eliminate in a day ?

Answer»

`1.3 xx 10^(-3)`
`1.3 xx 10^(-6)`
`1.94 N`
`1.94 xx 10^(-2) N`

ANSWER :B
Discussion
13.

What is meant by 'demineralised water ' and how can it be obtained ?

Answer»

Solution :What which is free from all CATIONS and anions is CALLED demineralised WATER. It is obtained by passing hard water first through CATION exchange RESIN and then through anion exchange resin.
Discussion
14.

The velocity of light is 3 xx 10^(10) cm/s. Express it in miles/hour.

Answer»

SOLUTION :Since, `1 cm = 6.214 XX 10^(-6)` miles and `1 s = 1/(3600)` HOUR.
Therefore, the CONVERSION factor for cm is:
`1 = (6.214 xx 10^(-6))/(1 cm)`
and that for second would be:
`1=(1/3600) "hours")/(1 s)`
Hence, `3 xx 10^(10) cm//s = (3 xx 10^(10) cm xx (6.214 xx 10^(-6) "miles")/(1 cm))/(1s xx (1/(3600 "hours"))/(1 s))`
`=(3 xx 10^(10) xx 6.214 xx 10^(-6))/(1/3600)`
`=6.711 xx 10^(8)` miles/hour
Discussion
15.

What is the oxidation number ofNi in Ni(CO)_4

Answer»

SOLUTION :OXIDATION number of NI in `Ni(CO)_4` is x+4(0)=0,x=0
Discussion
16.

Which of the following is used in high temperature thermomertry?

Answer»

NA
Ga
TI
HG

ANSWER :B
Discussion
17.

What is oxidation number of .C. in HClO_(4)andHClO_(3) ?

Answer»

Solution :In `HClO_(4)toCl^(+7)`
In `HClO_(3)toCl^(+5)`
Discussion
18.

Which reaction is possible?

Answer»

`KMnO_(4)+Na_(2)SO_(4) rarr`
`BaSO_(4)+KCI rarr`
`SrSO_(4) +Ni(NO_(3))_(2)rarr`
`ZnSO_(4)+BAS rarr`

Answer :D
Discussion
19.

Which of the following order is correct-

Answer»

`AlCl_(3) lt MgCl_(2) lt NaCl` , polarising power
`CO gt CO_(2) gt HCO_(2)^(-) gt CO_(3)^(2-)`: bond length
`BeCl_(2) lt NF_(3) lt NH_(3)`: dipole moment
`H_(2)S gt NH_(3) gt SiH_(4) gt BF_(3)`: bond angle

Solution :Polarising power of cations increases with the increasing charge.
`overset((+1))(NaCl) lt overset((+2))(MgCl_(2)) lt overset((+3))(AlCl_(2))`
Bond order`PROP(1)/("Bond length")`
Bond order=`("bond order of each C-O bond")/("Total no. of resonating structures")`
`CO to C-=O implies (2+1)/(1)=3.0`
`CO_(2) to O =C=O implies (2+2)/(2)=2.0`

Hence, the decreasing order of bond length is, `CO_(3)^(2-) gt HCO_(2)^(-) gt CO_(2) gt CO`
(c)
Correct order of dipole moment: `BeCl_(2) lt NF_(3) lt NH_(3)`
(d) Correct order of bond angle:
`underset(120^(@))(BF_(3)) gt underset(109^(@)28')(SiH_(4)) gt underset(107^(@))(NH_(3)) gt underset(94^(@))(H_(2)S)`
Discussion
20.

Water molecule has bent structure even it undergoes sp^(3) hybridization.

Answer»

SOLUTION :Due to the REPULSION between the two lone pair of ELECTRONS in water molecule, the STRUCTURE become bent.
Discussion
21.

Why can sugar (sucrose) melts on heating but common salt (sodium chloride) doesnot melt so easily ?

Answer»

Solution :Common salt (NaCl) is an ionic compound in which `Na^(+)` ions and `Cl^(-)` ions are held together by strong electrostatic forces of attraction. Hence, its MELTING point is very high. SUCROSE is a covalent compound and no ions are present. Molecules are held together by WEAK van der Waal forces and hydrogen bonds. Hence, it has LOW melting point.
Discussion
22.

Which oneamong thefollowingelementshas thelowestfirstionisationenthalpyand which of thehashighestfirstionisationenthalpy? Li, K , Ca , S andKr.

Answer»

Solution :Li belongs to the 2ndperiod. S TOTHE 3rdwhile K and Krbelongto the 4thperiod.BothLi and Kare ALKALI metalsbut the sizeof K isbiggerthan thatofLi . Furthersince alongany period, `Delta_(i) H_(1)` of alkalimetas is thelowestwhile of thatinertgas is THEHIGHEST. Thereforek hasthelowest`Delta_(i) H_(1)` while Krhas thehighest`Delta_(i) H_(1)`
Discussion
23.

Which pair of gases has the same average rate of diffusion at 25^(@)C?

Answer»

He and Ne
`N_(2)` and `O_(2)`
`N_(2)O` and `CO_(2)`
`NH_(3)` and `HCL`

Answer :C
Discussion
24.

underset(("Orange solid"))((A))overset(Delta)rarrunderset(("Yellow"))((B))+underset(("Green"))((C)) +underset(("Paramagnetic"))((D)) Compound (C) is also obtained on heating of:

Answer»

`(NH_(4))_(2)Cr_(2)O_(7)`
`NH_(4)CIO_(4)`
`NH_(4)NO_(3)`
None of these

Answer :A
Discussion
25.

Weakest acid among CH_(4)COOH, CH_(2)ClCOOH, CHCl_(2)COOH is ……..

Answer»

SOLUTION :`CH_(3)COOH`
Discussion
26.

Why are lithium salts commonly hydrated and those of the other alkali ions usually anhydrous ?

Answer»

Solution : LITHIUM is the smallest in size AMONG the alkali metals. Hence, `Li^(+)`ion can polarize water molecules more easily than other alkali metals.
As a RESULT, water molecules get ATTACHED to lithium salts as water of crystallization. Hence, lithium salts such as trihydrated lithium chloride are commonly hydrated.
As the size of the ions increases, their polarizing power decreases. Hence, other alkali metal ions usually form anhydrous salts.
Discussion
27.

The value of DeltaH for cooling 2 moles of an ideal monoatomic gas from 125^@ Cto 25^@ C at constant pressure will be [given C_p = 5/2 R] ………………. .

Answer»

`-250 R`
`-500 R`
500 R
`+250 R`

Solution :`T_(i) = 125^(@)C=398K`
`T_(f)=25^(@)C = 298K`
`DeltaH = nC_(P)(T_(i)-T_(f))`
`DeltaaH =2XX(5)/(2)R(298-398)`
`DeltaH =-500R`
Discussion
28.

Which of the following statements is trud about the science of atoms are molecules?

Answer»

We can see, weigh and perceive the atoms and MOLECULES through naked eyes.
It is possible to count the number of atoms and molecules in a GIVEN mass of MATTER through naked eyes and manually
We can establish a quantitative relationship between the mass and number of these particles ( atoms and molecules)
physical properties of matter can be qualitatively described using numerical values with suitable units

Solution :C)
Discussion
29.

The reagent used to convert RCOOH rarr RCH_(2)OH is

Answer»

`NaBH_(4)`
Na/Alcohol
Zn/Hg-HCl
`LiAIH_(4)`

SOLUTION :It is FACT.
Discussion
30.

The substance that spreading pollution is called .....

Answer»

SOLUTION :POLLUTANT
Discussion
31.

Which one of the following is a correct set?

Answer»

`H_(2)O, SP^(3),` BENT
`H_(2)O, sp^(2),` linear
`NH_(4)^(+),dsp^(2),` SQUARE PLANAR
`CH_(4),dsp,^(2)` tetrahedal

Solution :`H_(2)O, sp^(3),` bent
Discussion
32.

What is meant by Convection ?

Answer»

Solution :A FUNCTIONAL group is an atom or a specific combination of bonded atoms that react in a CHARACTERISTIC way, IRRESPECTIVE of ORGANIC molecule in which it is present. The reaction of an organic compound takes place at the functional group.
e.g., Alcohol -OH group
Ether -O-group
Discussion
33.

What will happen when Br_2//C Cl_4 react with (a) cis But-2-ene (b) trans But-2-ene.

Answer»


ANSWER :(a)RACEMIC MIXTURE of 2,3-Dibromobutane , (B) MESO 2,3-Dibromobutane
Discussion
34.

The structure of 2-Iodo-2-methylpropane is ……………………….. .

Answer»

SOLUTION :`CH_3-UNDERSET(I)underset(|)OVERSET(CH_3)overset(|)C-CH_3`
Discussion
35.

Which one of the following does not involve coagulation ?

Answer»

FORMATION of delta region
Petization
Treatment of drinking water by POTASH alum
Clotting of BLOOD by use of FERRIC chloride.

Solution :Peptization is the conversion of the particles of freshly precipitated substance into colloidal particles.
Discussion
36.

The value of K_(p) for the water gas reaction, CO +H_(2)O hArr CO_(2) +H_(2)is 1.06 xx 10^(5) at 25^(@)C . Calculate the standard free energy change for the reaction at 25^(@)C.

Answer»


Solution :`Delta_(r)G^(@) =- 2.303 rt LOG K = - 2.303 xx 8.314 xx 298 xx log ( 1.06 xx 10^(5))`
Discussion
37.

Total number of valence electrons in the molecule CH_(3)CHO is

Answer»

18
16
20
22

Answer :A
Discussion
38.

The reagent used in the conversion: Hg to HgO is

Answer»

`H_2O_2`
`FeSO_4`
`H_2O_2 ` + UREA
`H_2O_2 + H_2SO_4`

ANSWER :D
Discussion
39.

X and Y in the following reactions are :

Answer»




`X = R R' CH_(2)CN, Y = NAOH`

SOLUTION :
Discussion
40.

Which of the following set has atomic numbers of only representative elements ?

Answer»

2,10,17,35
2,12,22,32
3,15,35,45
4,20,36,79

Answer :a
Discussion
41.

Which of the following pairs of compounds is ring-chain isomer ?

Answer»

`CH_(3)-undersetunderset(OH)(|)CH-undersetunderset(OH)(|)CH-CH_(3)`



SOLUTION :On BRIDGED CARBON double BOND can.t exist
Discussion
42.

Which one of the followingis an aromatic compounds

Answer»




ANSWER :a
Discussion
43.

What units do the following abbreviations represent ? (a) mug (b) dm (c) ps (d) kA (e) m mol ?

Answer»


ANSWER :(a) mixrogram (b) decimetre (c) PICO SECOND (d) kiloampere (e) MILLI mol
Discussion
44.

The tatio of the cationic radius to anionic radius in an ionic crystal is greater than 0.732. Its co-ordination number is

Answer»

1
4
6
8

Solution :When radius RATIO`r^(+)//r^(-)gt0.732`, the cation is PRESENT at the CUBIC side in a simple cubic lattice of anions. The co-ordination NUMBER of cation =co-ordination number of anion=8
Discussion
45.

Whichof thefollowingis mostelectropositive?

Answer»

`NA`
`Na^(+)`
`K`
`K^(+)`

ANSWER :C
Discussion
46.

What is the value of gas constant R in J mol^(-1 ) K^(-1)?

Answer»

82.1
`8.314 XX 10^7`
`8.314`
`0.0821 9`.

ANSWER :C
Discussion
47.

Which one is present in troposphere?

Answer»

`CO_2`
`H_2 O`
`N_2`
All of these

Solution :All of these
Discussion
48.

Write the atomic number of the element in the third period and group 17 of the period table.

Answer»

Solution :In the third period third SHELL is filled and there are 8 elements (3S 3p). These will be two Ar(18). So element 11 and 12 are s BLOCK while 13 to 18 are p block belonging to groups 13 to 18. So the elment in the `17^th` GROUP must have an atomic number 17 (CHLORINE).
Discussion
49.

The solubility product (K_(sp)) of the following compound s are given at 25^(@)C {:("Compound" ,K_(sp)),(AgCl,1.1xx10^(-10)),(Agl,1.0xx10^(-16)),(PbCrO_(4),4.0xx10^(-10)),(Ag_(2)CO_(3),8.0xx10^(-12)),(,):} The mostsoluble and least soluble compound are respectively

Answer»

`AGCL and PbCrO_(4)`
`AgI and Ag_(2)CO_(3)`
`AgCl and Ag_(2)CO_(3)`
`Ag_(2)CO_(3)and AgI`

Solution :The 1 st three salts are of the type AB for which
`S=sqrt(K_(sp))`, i.e., `10^(-5)M(AgCl), 10^(-8) M (AgI), 2xx10^(-7)M (PbCrO_(4))`. Last salt isof the type `A_(2)B` for which `S=(K_(sp)//4)^(1//3)=(2xx10^(-12))^(1//3)~=10^(-4)` M. Thus, most soluble is `Ag_(2)CO_(3)` and least soluble is AgI.
Discussion
50.

Which one of the following is diamagnetic ?

Answer»

`O_(2)`
`O_(2)^(2-)`
`O_(2)_(2+)`
NONE of these

Solution :`O_(2)^(2-)` is diamagnetic. Additional TWO electrons are paired in anti-bonding MOLECULAR orbits `pi_(2py) and pi_(2py).`
Discussion