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 one of the following pairs of atoms/ions have identical ground state configurations ?

Answer»

`Li^+and He^+`
`CL^- and AR`
`NA and K `
`F^+ and Ne`

SOLUTION :`Cl^(-1)` has configuation as argon `Ar = 3s^2 3p^6`
Discussion
2.

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

Answer»

Solution :Because of smallest size among alkali metal , `Li^(+)` can polarize water MOLECULES more easily than the other alkali metal ions and hence get ATTACHED to lithium salts as water of crystallization . For example , lithium chloride CRYSTALLISES as LICL . `2H_(2)O` but sodium chloride crystallise as NaCl .
Discussion
3.

What happens when a borax solution is acidfied ? Write a balanced equation for the reaction.

Answer»

Solution :BORIC acid is formed, `Na_(2)B_(4)O_(7)+2HCl + 5H_(2)O rarr 2NaCl +4H_(3)BO_(3)`
Discussion
4.

Threshold wavelength of a metal is lamda_(0). The de Broglie wavelength of photoelectron when the metal is irradiated with the radiation of wavelength lamda is:

Answer»

`[(h lamdalamda_(0))/(2cm)]^((1)/(2))`
`[(h(lamda-lamda_(0)))/(2cmlamdalamda_(0))]^(1//2)`
`[(h(lamda_(0)-lamda))/(2cmlamdalamda_(0))]^(1//2)`
`[(hlamdalamda_(0))/(2mc(lamda_(0)-lamda))]^(1//2)`

SOLUTION :Absorbed energy=Threshold energy+Kinetic energy of photoelectron
`h(C)/(lamda)=(hc)/(lamda_(0))+E`
`E=hc[(1)/(lamda)-(1)/(lamda_(0))]` . . . .(i)
DE Broglie wavelength can be CALCULATED as
`lamda=(h)/(sqrt(2Em))`.. . . (ii)
From eqs. (i) and (ii)
`lamda=[(hlamdalamda_(0))/(2mc(lamda_(0)-lamda))]^(1//2)`
Discussion
5.

Whichquantumnumberindicates theorientationof oribitalsspaceundermagneticfield ?

Answer»

N
s
L
m

ANSWER :D
Discussion
6.

Which isomer of hexane has only two different sets of structurally equivalent hydrogen atoms ?

Answer»

2, 2-dimethylbutane
2-methylpentane
3-methylpentane
2, 3-dimethylbutane

Solution :`{:(""CH_(3)" "CH_(3)),("|""|"),(CH_(3)-CH-CH-CH_(3)):}`
2, 3-Dimethylbutane has TWO SETS of structure-rally EQUIVALENT hydrogens(twelve `1^(@)` and two `3^(@)`)
Discussion
7.

Which of the following is a semiconductor?

Answer»

C
Pb
GE
Sn

Solution :Ge
Discussion
8.

What happened when we heating glass ?

Answer»

Solution :On HEATING, the glass MELTS and the SURFACE of the liquid tends to take the rounded SHAPE at the edges which makes the edges which makes the edges smooth. This is called FIRE polishing of glass.
Discussion
9.

Which of the following are arranged in increasing order of solubilities ?

Answer»

`CaCO_(3) LT KHCO_(3) lt NaHCO_(3)`
`NaHCO_(3) lt KHCO_(3) GT CaCO_(3)`
`KHCO_(3)lt NaHCO_(3) gt CaCO_(3)`
`CaCO_(3) lt NaHCO_(3) gt KHCO_(3)`

Answer :B
Discussion
10.

Which of the following is the correct representation of Charles's law ?

Answer»




ANSWER :C
Discussion
11.

The shown snapshots represents five molecular level scenes of a gaseous mixture as it reaches equilibrium over a time in a vessel of volume 1 litre. Reaction : X_(2)(g)+Y_(2)(g)hArr2XY(g) Which part of the 'film strip' represents the equilibrium irrespective of the value of each particle in terms of moles?

Answer»

A
B
C
None of these

Answer :C
Discussion
12.

The shown snapshots represents five molecular level scenes of a gaseous mixture as it reaches equilibrium over a time in a vessel of volume 1 litre. Reaction : X_(2)(g)+Y_(2)(g)hArr2XY(g) In snapshot 'A-E' if each particle represents 0.1 mole then on introducing another 0.4 mole each of X_(2) and Y_(2) in scene A, the equilibrium stage can be represents by which of the picture?

Answer»




ANSWER :A
Discussion
13.

The shown snapshots represents five molecular level scenes of a gaseous mixture as it reaches equilibrium over a time in a vessel of volume 1 litre. Reaction : X_(2)(g)+Y_(2)(g)hArr2XY(g) If each particle represents 0.2 moles then what will be the value of reaction quotient (Q) for scene B?

Answer»

0.36
0.18
4
5

Answer :C
Discussion
14.

What are chemical messengers?

Answer»

Solution :The interatomic attractive forces which HOLDS the CONSTITUENT atoms/ions TOGETHER in a molecue are called CHEMICAL BONDS.
Discussion
15.

What do you understand by the terms : (i) hydrogen economy, (ii) hydrogenation, (iii) syngas ,(iv)water-gas shift reaction ,(v) fuel-cell ?

Answer»

Solution :(i) hydrogen - economy : The basic principle of hydrogen - economy is the transportation and storage of energy in the form of liquid or gaseous dihydrogen.
(ii) hydrogenation : Hydrogenation of vegetable oils using nickel as catalyst gives edible fats (margarine and vanaspati ghee)
(III) syngas : The mixture of CO and `H_2` is used for the synthesis of methanol and a number of hy drocarbons so it is called synthesis gas or syngas.
(iv) water gas shift reaction : The production of dihydrogen can be increased by reacting carbon MONOXIDE of syngas mixture with STEAM in the presence of iron chromate as catalyst.
`ubrace(CO_((g)) + H_2O_((g)))_("Water-gas")+ underset"Steam catalyst Fecro4"overset"673 K"to CO_(2(g))+ H_(2(g))`
(v) fuel-cell : Fuel-cell is a device which converts, the energy PRODUCED during the combustion of a fuel directly into electrical energy Dihydrogen is used in Hydrogen-Oxygen fuel-cells for generating electrical energy. In this 70 - 85% combustion energy is converted into electrical energy.
Discussion
16.

Which of the following are easily stopped by air ?

Answer»

X-rays
UV -rays
`GAMMA`-rays
`ALPHA`-rays

Solution :Heavy `alpha` -particle are easily stopped by AIR.
Discussion
17.

What will be the value of pH of 0.01 mol dm^(-3) cH_(3)CO OH (K_(a) = 1.74 xx 10^(-5))?

Answer»

3.4
3.6
3.9
`3.0`

Solution :`pH = (1)/(2) (pK_(a)-LOG C)=(1)/(2) [-log (1.74xx10^(-5))-log 10^(-2)]`
`=(1)/(2) [ (5-0.2405) + 2] = (1)/(2) (6.76) = 3.38 ~= 3.4`.
Discussion
18.

Which one of the following statement is not correct?

Answer»

DDT and BHC are not good INSECTICIDES because they are highly soluble in WATER
DDT and BHC are not good insecticides because they are ABSORBED by the soil and CONTAMINATE root crops
Aldrin is not a good insecticide because it isnot biodegradable
All the above are incorrect

Solution :DDT and BHC are not MUCH soluble in water.
Discussion
19.

When gas molecules collide on the walls of the vessel, the energy of the molecules changes into

Answer»

Heat
Temperature
Light
None

ANSWER :D
Discussion
20.

When atoms are bombarded with alpha particles, only a few in million suffer deflection, others pass out undeflected. This is because

Answer»

The force of repulsion on the moving alpha PARTICLE is SMALL
The force of attraction on the alpha particle to the oppositely charged ELECTRONS is very small
There is only one nucleus and large number of electrons
The nucleus OCCUPIES much smaller volume compared to the volume of the ATOM

Solution :The nucleus occupies much smaller volume compared to the volume of the atom
Discussion
21.

Which compound has incomplete octet?

Answer»

`H_(2) O, SP^(2)`, linear
`NH_(4)^(+)DSP^(2)` square planar
`H_(2) O, sp^(3)` , angular
`CH_(4) , dsp^(3)` tetrahedral

Solution :`H_(2) O, sp^(3)` , angular
Discussion
22.

Whichelementhas (a) Twoshells , both ofwhich arecompletely filled withelectrons ? (b) the electronicconfiguration2, 8, 2 ? (c) a totalof threeshellswith fourelectronsin thevalenceshell ? (d)a total of twoshells ,withthreeelectronsin the valenceshell (e)twiceas manyelectronsin the second shellas in its firstshell ?

Answer»

Solution :(a) Sincenoblegases (Group 18) haveall theirshells completely filledwith electronsthereforethe given element must be a noble gas. Since it has twocompleted shell(2,8)it belongsto 2ndperiod. Thus, theelements is neon (Ne).
(b) Sinceeach periodbeginswith the filling of anew shell, thereforethe elementhavingelectronicconfiguration2, 8, 2belongsto 3rdperiod. Further, sincethe element has twoelectronsin theoutermostshell,it belongsto group 2. Inother words the given element belongs to group2 of the 3rd period. thusthe element ismagnesium (Mg).
(c) Sincethe given element has totalthree energy shells with a total of4 electronsin the VALENCE shelltherefore, the electronicconfigurationof the element is2, 8, 4 , . In otherwordsthe elementbelongstogroup 14 of the3rdperiod. Thus the elementis silicon (Si).
(d)Since the givenelement has a total of two energyshellswith threeelectronsin the valence shells therefore theelectronicconfigurationof the elements 2, 3. Inother words theelementbelongstogroup 13 ofthe 2ndperiod.thus theelement is boron(B).
(e) Thegiven elementhas twoshells. But in THEFIRST shellsthe maximumof ELECTRONSIS 2. Sincethe NUMBER of theelectrons in the 2ndshell istwicethe electrons in the Istshell ,thereforethe numberofelectronsin the 2ndshell is 4 and thecompleteelectronicconfigurationof the elementis 2, 4. In otherwordsthe givenelementbelongsto GROUP14 of the2ndperiod. Thus the element iscarbon (C).
Discussion
23.

Which of the following alkaline earth metal sulphates has its hydration enthalpy greater than its lattice enthalpy ?

Answer»

`BaSO_(4)`
`SrSO_(4)`
`CaSO_(4)`
`BeSO_(4)`

SOLUTION :Among alkaline earth METAL SULPHATES , lattice enthalpy remains almost constant but HYDRATION enthalpy decreases down thegroup . Thus , `BeSO_(4)` has higher hydration enthalpy as compared to lattice enthalpy .
Discussion
24.

What is compressibility factor ?

Answer»

SOLUTION :`Z=(PV)/(NRT)`
Discussion
25.

What isZemaneffectand starkeffect ?

Answer»

SOLUTION :Thesplittingof spectrallinesin THEPRESENCE ofmagneticfieldis Zemaneffectand inelectricalfieldis starkeffect.
DUETO thiseffectspectrallinesare DIVIDEDIN tosmalldistance .
Discussion
26.

What is the formula of borax ?

Answer»

Solution :`Na_(2)B_(4)O_(7).10H_(2)O` or BORIC ACID / DIBORANE .
Discussion
27.

Which of the following molecules contain more enol content at equilibrium

Answer»

`OHC - CH_2 - CHO`
`CH_3COCH_2COOCH_3`
`CH_2(COOH)_2`
`CH_3COCH_3`

Solution :CHO GROUP is more electron with DRAWING than keto group and ester group.
Discussion
28.

Which metal is used to prepare Lassaigne's extract?

Answer»

Copper
Sodium
Aluminium
Iron

Answer :B
Discussion
29.

whis is true

Answer»

ROCHELLE's salt is FERROELECTRIC while LEAD ziroconate is antiferroelectric
Rochelle's salt is antiferroelectric and lead ZIRCONATE is ferroelectric.
Both are ferroelectric
Both are antiferroelectric

ANSWER :2
Discussion
30.

Two successive member of Alkane series differ from each other by a……. Group

Answer»

`-CHO`
`-C_(2)H`
`-CH_(2)`
`CH_(2)CH_(2)`

ANSWER :C
Discussion
31.

Which one of the following has bond order as 2 ?

Answer»

1) `N_(2)`
2) `C_(2)H_(4)`
3) `CH_(4)`
4) HCN

Solution :`C_(2)H_(4)`
Discussion
32.

What is the strength of H_2O_2 solution whose volume is 12 ?

Answer»

`31.20`
36.42
31.34
33.44

Solution :Weight STRENGTH =`"VOLUME strength X 68"/22.4 = (12xx68)/22.4`= 36.42 g
Discussion
33.

What are diagram and diagram ?

Answer»

Solution :(I)`PSI` itself has no physical meaning but it REPRESENTS an antomic orbital.
(ii) `Psi^(2)`is related to the probability of finding the electrons with in a given volume of SPACE.
Discussion
34.

which of the following will not disolace hydrogen ?

Answer»

Ba
Pb
HG
Sn.

Solution :MERCURY (Hg) will not DISPLACE HYDROGEN.
Discussion
35.

Which of the following has giant convalent structure ?

Answer»

NaCl
`SiO_(2)`
`AlCl_(3)`
`PhO_(2)`

Solution :(b)
Discussion
36.

Which of the following designation is impossible ?

Answer»

4f
5g
2d
6p

Answer :C
Discussion
37.

What is the oxidation number ofFe in Fe(CO)_5

Answer»

SOLUTION :Oxidation NUMBER of FE in `Fe(CO)_s` is x+5 (0)=0 or x=0
Discussion
38.

Which of the following is the best conductor of electricity?

Answer»

`1M HNO_3`
` 1MH_2CO_3`
` 1MH_3PO_4`
` IM H_2SO_4`

SOLUTION :dibasic ,strong acid ` ALPHA =1`
Discussion
39.

Volume V_1 ml of 0.1 K_(2) Cr_(2) O_(7) is needed for complete oxidation of 0.67g N_(2)H_4 in acidic medium The volume of 0.3 M KMnO_4 need for same oxidation state in acidic medium will be

Answer»

`2/5 V_(1)`
`5/2 V_1`
`113V_1`
can.t say

Solution :`V_(1)M_1 xxn_1 ` (n - factor) `= V_(2) M_2 xxn_2`
`V_(1) XX 0.1 xx 6 = V_2 xx0.3 xx 5`
Vol. of `KMnO_4 ,V_(2)=2/5 V_1`
Discussion
40.

When H_(2)O_(2) is added to acidified ferrous sulphate solution

Answer»

Electrons are GAINED by `Fe^(2+)`
Electrons are lost by `Fe^(2+)`
No loss (or) gain of electrons
Iron hydroxide is precipitated

Answer :B
Discussion
41.

Which of the following involve oxidation and reduction?

Answer»

`2Na+2H_(2)Orarr2NaOH+H_(2)`
`2CuI_(2)rarr2Cu+l_(2)`
`NH_(4)CI+NaOHrarrNaCI+NH_(3)+H_(2)O`
`4KCN+Fe(CN)_(6)rarrK_(4)[Fe(CN)_(6)]`

Solution : In both the REACTIONS, there is change in O.N of the SPECIES
Discussion
42.

Which compound will be formed when ethyl acetate and excess of ethyl magnesium bromide allowed to react and the product is hydrolysed ?

Answer»

3-Ethyl -3-pentanol<BR>3-Methyl-3-pentanol
Hexan-3-ol
2-Methyl-2-propanol

Solution :`{:(""O""C_(2)H_(5)),("||""|"),(CH_(3) - C - OC_(2)H_(5) overset((i)2C_(2)H_(5)MGBR)overset((II) H_(2)O)rarr CH_(3) - C - OH + Mg (OH) Br + Mg (OC_(2)H_(5)) Br ),("|"),(""C_(2)H_(5)),("3-Methyl -3-pentanol"):}`
Discussion
43.

What is another name of ideal gas equation ? Why ?

Answer»

SOLUTION :Ideal GAS equastion is KNOWN as equation of STATE. Because ideal gas equation PV = nRT is relation of p, V, n and T, so, its indicated state of gas.
Discussion
44.

To a sample of an element A (at.wt.=70) another element B (atomic wt = 120) is to be added as an impurity. For the ratio of the atoms in the mixture to be 1:10^(-9),x xx10^(-8)g of B will be required for 35g of A. Find the value of x.

Answer»


Solution :`(A)/(B)=(1)/(10^(-9))` ATOMS
if A = n atom = wt = `(n)/(6XX10^(23))xx70`
`B = nxx10^(-9)` atoms
IMPLIES wt = `(nxx10^(-9))/(6xx10^(23))xx120`
given `(nxx70)/(6xx10^(23))=35implies(n)/(6xx10^(23))=(35)/(70)=(1)/(2)`
`therefore (nxx10^(-9)xx120)/(6xx10^(23))=(1)/(2)xx120xx10^(-9)=6xx10^(-8)`
`x=6`
Discussion
45.

Two flasks are connected by a valve: One of them with volume 5L contains 0.1 mol of H_(2) at 27^(@)C and the other of volume 2L contains 0.1 mol of N_(2) at the same temperature. If the valve is opened keeping temperature constant, then at equilibrium the contribution of H_(2) gas to the total pressure of the gas mixture-

Answer»

is the same as that of `N_(2)` gas
is GREATER than that of `N_(2)` gas
is LESS than that of `N_(2)` gas
cannot be predicted

Answer :A
Discussion
46.

What are the different types of equilibrium? Explain with example?

Answer»

Solution :Physical equilibrium: A SYSTEM in which the amount of matter constituting different phases does not CHANGE with time is said to be in physical equilibrium. `H_(2)O(s) hArrH_(2)O(I)`Solid-liquid equilibrium.
(i) Chemical equilibrium: Chemical reactions in which the forward and BACKWARD reactions are proceeding at the same RATE and no macroscopic change is observed is said to be in chemical equilibrium. `H_(2)(g) + I_(2) (g) HARR 2HI(g)`
Discussion
47.

Write the characteristics of chemical equilibrium.

Answer»

Solution :1. Chemical EQUILIBRIUM is DYNAMIC.
2. Equilibrium REACTION will not come to an end.
3. Equilibrium is attained only in a closed system.
4. Catalyst does not alter the equilibrium state.
Discussion
48.

Which metal is present in chlorophyll which is present in leaves of plants?

Answer»

MG
CO
CU
FE

ANSWER :A
Discussion
49.

Which of the following compounds when started with one mole, will give two moles of CH_4whentreated with excess of methyl magnesiuin broinide?

Answer»

`HOOC - CH_2 - CH_2-OH`
`HOCH_2 - CH_2 - NH-CH_3`

`HOH_2C - CH_2OH`

SOLUTION :WURTZ REACTION
Discussion
50.

Whichof the following compoundsshall not produce propene by reaction with HBr followedby elimination(or) only direct elimination reaction?

Answer»


`CH_(3)-CH_(2)-CH_(2)-OH`
`H_(2)C=C=O`
`CH_(3)-CH_(2)-CH_(2)`Br

Answer :c
Discussion