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 only correct combination in which one compound has only one carbon in its parent chain ?A. (I)(i)(Q)B. (II)(ii)(R)C. (III)(ii)(R)D. (IV)(i)(P)

Answer» Correct Answer - C
IUPAC name of `Ph-CH_2-NH-CH=O` is N-Phenylmethylmethanamide [Parent chain with one carbon atom only ]
`Ph-NH-CH_2-CH=O overset("Tautomerism")hArr Ph-NH-CH=CH-OH`(enol)
Discussion
2.

The least and most stable resonating structure respectively are : A. 1,4B. 2,3C. 4,1D. 3,2

Answer» Correct Answer - A
1 is least stable since charge separation is done and +ve charge is towards -m group. 4 is most stable due to no charge separation and more linearly conjugated.
Discussion
3.

What is the actual volume occupied by watr molecules present in 20 `cm^(3)` of water?A. 20 `cm^(3)`B. `10 cm^(3)`C. `40 cm^(3)`D. `24.49 dm^(3)`

Answer» Correct Answer - B
It is a fact.
Discussion
4.

You’re reading the book _____ I wanted to read. A) when B) who C) which D) where

Answer»

Correct option is C) which
Discussion
5.

Which of the following coordinate complexes is an exception to EAN rule? (Given At. No. Pt =78, Fe=26, Zn=30, Cu=29]A. `[Pt(NH_(3))(6)]^(4+)`B. `[Fe(CN)(6)]^(4-)`C. `[Zn(NH_(3))_(4)]^(2+)`D. `[Cu(NH_(3))_(4)]^(2+)`

Answer» Correct Answer - D
EAN = Z-X +Y
(a) EAN = 78-4+12=86
b) EAN = 26-2+12=36
C) EAN 30-2 +8 = 36
(d) EAN = 29-2+8=35
Discussion
6.

Which of the following statements is INCORRECT in case of Hofmann bromamide degradationn?A. Reaction is useful for decreasing length of carbon chain by one carbon atomB. It gives tertiary amineC. It gives primary amineD. Aqueous or alcoholic KOH is used with bromine.

Answer» Correct Answer - B
Hoffmann hypobromite degradation
`R-CONH_(2) + Br_(2) + 4NaOH to R-NH_(2) + Na_(2)CO_(3) + 2NaBr + 2 H_(2)O`
Incorrect statement B
Discussion
7.

Explain `[Co(NH_3)_6]^(3+)` is an inner orbital complex whereas `[Ni(NH_3)_6]^(2+)` is an outer orbital complex.

Answer» In the presence of `NH_3` the 3d electrons pair up leaving two d-orbitals empty to be involved in `d^(2)sp^(3)` hybridisation forming inner orbital complex in case of `[Co(NH_3)_6]^(3+)`. In `Ni(NH_3)_6^(2+)`, Ni is in `+2` oxidation stale and has `d^(8)` configuration, the hybridisation. Thus there is no unpaired electron.
Discussion
8.

Which of the following statements is INCORRECT for pair of elements Zr-Hf?A. Both possess same number of valence electrons.B. Both have identcial atomic sizes.C. Both have almost identical ionic radii.D. Both of these belong to same period of periodic table.

Answer» Correct Answer - D
These are chemical twins
Zr belongs to 5th period and 4th group.
Hf belongs to 6th period and 4th group.
Discussion
9.

Those are old cars _____ only take leaded petrol. A) who B) when C) on D) which

Answer»

Correct option is D) which
Discussion
10.

Oxidation number of nitrogen in which among the oxide of nitrogen is the lowest ?A. Nitric oxideB. Nitrous oxideC. Nitrogen dioxideD. Nitrogen trioxide

Answer» Correct Answer - B
(a) Nitric oxide , NO x - 2 `= 0 implies x = + 2`
(b) Nitrous oxide ` , N_(2)O 2x - 2 = 0 implies x = + 1`
(c) Nitrogen dioxide , `NO_(2)`
x + 2(-2) = 0 `implies x = + 4`
(d) Nitrogen trioxide `NO_(3)`
`x + 2x (-3) = 0 implies x = + 6`
Thus , in nitrous oxide , oxidation number of nitrogen is lowest .
Discussion
11.

Aldehyde or ketones when treated with `C_(6)H_(5)-NH-NH_(2)`. The product formed isA. semicarbazoneB. phenylhydrzaoneC. hydrazoneD. oxime

Answer» Correct Answer - B
`R-C = O + H_(2) N-NH = C_(6)H_(6) to R-CH = N.NHC_(6)H_(5) + H_(2)O`
`R-overset( R)overset(|)C=O + H_(2)N - NH - C_(6)H_(5) to R-overset(R ) overset(|)C = N.NHC_(6)H_(5) + H_(2)O`
Ald or ketone phenyl hydrazone
Discussion
12.

What is the quantity of hydrogen gas liberated when `46 g` sodium reacts with excess ethanol ? (Given atomic mass of `Na = 23`)A. `2.4 xx 10^(-3)` kgB. `2.0 xx 10^(-3)` kgC. `4.0 xx 10^(-3)` kgD. `2.4 xx 10^(-2)` kg

Answer» Correct Answer - B
`2C_(2)H_(5)OH + 2Na to underset("sod. Ethoxide") (2C_(2)H_(5)Ona + H_(2)) uarr`
46 of ef Na means 2 moles of Na liberates one mole of `H_(2)` i.e., 1g molar mass i.e., i.e. `2 xx 10^(3)` kg.
Discussion
13.

Which among the following metals is employed to provide cathodic protection to iron ?A. ZincB. NickelC. TinD. Lead

Answer» Correct Answer - A
Cathodic protection of iron involves using another more reactive metal or a sacrifical anode . Since , in electrochemical series , Zn is place above Fe , so it is used for such action .
Discussion
14.

Which halogen forms an oxoacids that contains the halogen atom in tripositive oxidation state ?A. FluorineB. ChlorineC. BromineD. Iodine

Answer» Correct Answer - B
HOCIO or `HCIO_(2)` i.e., chlorous acid only stable oxyacid among other halogen oxyacids.
Discussion
15.

What is the pH of millimolar solution of ammonium hydroxide which is 20% dissociated ?A. 3.699B. 10.301C. 4.691D. 9.301

Answer» Correct Answer - B
Concentration of `NH_(4)OH` solution = 0.001 M
Degree of dissociation = `20 % = (20)/(100) = 0.2`
Concentration of `OH^(-)` i.e., `[OH^(-)] =`
Concentration of solution `xx` degree of dissociation
`= 0.001 xx 0.02 = 2 xx 10^(-4)`
`because [H^(+)] [OH^(-)] = 1 xx 10^(-14)`
`therefore [H^(+)] = (1 xx 10^(-14))/(2 xx 10^(-4)) = (1)/(2) xx 10^(-10)`
Again `, because p H = - log [H^(+)]`
`therefore pH = - log ((1)/(2) xx 10^(-10))`
= `- log (-10 - 0.3010) = 10.3010`
Discussion
16.

Solubility of which among the following solids in water changes slightly with temperature?A. `KNO_(3)`B. `NaNO_(3)`C. KBrD. NaBr

Answer» Correct Answer - D
Solubility of `KNO_(3), NaNO_(3)` and KBr increases with increases in temperature. While solunility of NaBr change slighltly with temperature.
Discussion
17.

Solubility of which among the following substances in water increases slightly with rise in temperature ?A. Potassium bromideB. Potassium chlorideC. Potassium nitrateD. Sodium nitrate

Answer» Correct Answer - B
KCl has large hydration energy than its lattice energy , so it evolves energy on dissolving in water . Consequently , with rise in temperature its solubility increases
Discussion
18.

The work done when two mole of an ideal gas is compressed form a volume of `5 m^(3)` to `1 dm^(3)` at 300 K , under a pressure of 100 kPa isA. `499.9` kJB. `-499.9 `kJC. `-99.5` kJD. `42495`kJ

Answer» Correct Answer - A
Work done , W = `- P_(ext") (V_(2) - V_(1))`
Here , `P_("ext") = 100 k Pa`
`V_(1) = 5 m^(3) = 5 xx 10^(3) L implies V_(2) = 1 dm^(3) = 1 L`
`therefore W = -100 xx (1 - 500)`
` = - 499900 k PaL`
`= - 499900 J = - 499.9 kJ ( because 1 k Pa L = 1 J)`
Discussion
19.

What is the molality of a solution containing 200 mg of urea ( molar mass 60 g `mol^(-1)`) dissolved in 40 g of water ?A. `0.0825`B. `0.825`C. `0.498`D. `0.0013`

Answer» Correct Answer - A
Molality (m) `= ("mass of solvent (in g)" xx 1000)/("molecular weight of solute" xx "mass of solvent (in g)")`
`= (200 xx 10^(-3) xx 1000)/(60 xx 40) = 0.0833`
Discussion
20.

The molarity of solution containing `15.20 g` of urea, (molar mass = 60) dissolved in `150 g` of water isA. `1.689 "mol" kg^(-1)`B. `0.1689` mol `kg^(-1)`C. `0.5922` mol `kg^(-1)`D. `0.2533` mol `kg^(-1)`

Answer» Correct Answer - A
`W_(2) = 15.20g`
`M_(2) = 60g mol^(-1)`
`W_(1) = 150 g`
m = ?
Calculation : To Calculate molality
`m=(W_(2))/(M_(2) xx W_(1)(kg))`
`=(15.20 xx 10^(-3)kg)/(60 xx 10^(-3) kg mol^(-1) xx 150 xx 10^(-3) kg)`
`=(15.20 xx 1000)/(60 xx 150) = (15.2 xx 10)/( 6 xx 15)`
`m=(15.2 xx 10)/(90) = 15.2/9 = 1.689 mol kg^(-1)`
Discussion
21.

The molarity of solution containing `15.20 g` of urea, (molar mass = 60) dissolved in `150 g` of water isA. `1.689 "mol" kg^(-1)`B. `0.1689` mol `kg^(-1)`C. `0.5922` mol `kg^(-1)`D. `0.2533` mol `kg^(-1)`

Answer» Correct Answer - A
`W_(2) = 15.20g`
`M_(2) = 60g mol^(-1)`
`W_(1) = 150 g`
m = ?
Calculation : To Calculate molality
`m=(W_(2))/(M_(2) xx W_(1)(kg))`
`=(15.20 xx 10^(-3)kg)/(60 xx 10^(-3) kg mol^(-1) xx 150 xx 10^(-3) kg)`
`=(15.20 xx 1000)/(60 xx 150) = (15.2 xx 10)/( 6 xx 15)`
`m=(15.2 xx 10)/(90) = 15.2/9 = 1.689 mol kg^(-1)`
Discussion
22.

What type of sugar molecule is present in DNA ?A. D-3-deoxyriboseB. D-riboseC. D-2-deoxyriboseD. D-Glucopyranose

Answer» Correct Answer - C
It is a fact.
Discussion
23.

The work done during combustion of `9 xx 10^(-2)` kg of ethane, `C_(2)H_(6)(g)` at 300 K is (Given R=8.314 J `deg^(-1) mol^(-1)`, atomic mass C = 12, H=1)A. 6.236 kJB. `-6.236` kJC. 18.71 kJD. `-18.71` kJ

Answer» Correct Answer - C
Ethane on combustion gives `CO_(2)` and `H_(2)O` as
`C_(2)H_(6)(g) + 7/2 O_(2)(g) to 2CO_(2)(g) + 3H_(2)O(l)`
`Deltan = sumn_(g)("product") - sum n(g) ("reactant")`
`=(2)-(1+3.5) = -2.5`
W=`-Deltan RT`
`=(-2)(-2.5) xx 8.314 xx 300`
`=625.55` J
`=6.2355` kJ
The molar mass of `C_(2)H_(6)` is =30 g mol
For 30 g, `W=+6.2 355` kJ
For 90g, `W = 3 xx 6.2355 kJ = 18.71` kJ
Discussion
24.

What is the hybridization of carbon atoms in fullerence?A. `SP^(3)`B. SPC. `SP^(2)`D. `dSP^(3)`

Answer» Correct Answer - C
In Fullerence, C undergo `sp^(2)` hybridization.
Discussion
25.

A molecule of Stachyose contains how many carbon atoms?A. 6B. 12C. 18D. 24

Answer» Correct Answer - D
The molecular formula of stchyose is `C_(24)H_(42)O_(21)`.
Discussion
26.

Which element among the following does NOT form diatomic molecules?A. ArgonB. OxygenC. NitrogenD. Bromine

Answer» Correct Answer - A
Argon is monoatomic. While others are oxygen `(O_(2))`, Nitrogen `(N_(2))` and Bromine `(Br_(2))` diatomic.
Discussion
27.

Which of the following is used as antiseptic ?A. ChloramphenicolB. BithionalC. CimetidineD. Chlordiazepoxide

Answer» Correct Answer - B
Informative.
Discussion
28.

Which among the following reactions is an example of pseudo first order reaction?A. Inversion of cane sugarB. Decomposition of `H_(2)O_(2)`C. Conversion of cyclopropane to propeneD. Decomposition of `N_(2)O_(5)`

Answer» Correct Answer - A
The hydrolysis of `C_(12)H_(22)O_(11)` by using dil HCl is pseudo first order reaction.
`C_(12)H_(22)O_(11) + H_(2)O overset("dil" HCl) to C_(6)H_(12) O_(6) + C_(6)H_(12)O`
In this conc. Of `H_(2)O` is taken as constant hence rate law expression is `R=k[C_(12) H_(22)O_(11)]` only.
Discussion
29.

The compound used in the treatment of lead poisoning is : (1) desferrioxime B (2) Cis-platin (3) D-penicillamine (4) EDTA

Answer»

The Correct option is (4) EDTA
Discussion
30.

The amino acid, which is basic in nature isA. HistidineB. TyrosineC. ProlineD. Valine

Answer» Correct Answer - A
Informative.
Discussion
31.

In Preparation of sulphuric acid from sulphur dioxide in lead chamber process. What substance is used as a catalyst?A. Manganese dioxideB. Vanadium pentoxideC. Nitric oxideD. Raney Nickel

Answer» Correct Answer - B
Lead chamber process:
The different steps are
(i) `2H_(2)O + NO to HNO_(3) + 3H^(+)`
(ii) `S + O_(2) to SO_(2)`
(iii) `2HNO_(3) + 2SO_(2) to H_(2)O + NO + NO_(2) + 2SO_(3)`
(iv) `SO_(3) + H_(2)O to H_(2)SO_(4)`
Net reaction:
`2SO_(2) + 2H_(2)O + O_(2) overset(NO) to 2H_(2)SO_(4)`
Discussion
32.

Which among the following equation represents the reduction reaction taking place in lead accumulator at positive electrode, while it is beings used as a source of electrical energy?A. `Pb to Pb^(2+)`B. `Pb^(4+) to Pb`C. `Pb^(2+) to Pb`D. `Pb^(4+) to Pb^(2+)`

Answer» Correct Answer - D
In lead accumulator reduction reaction is
`underset(O.N.=+4)underset(darr)(PbO_(2)(s)) + 4H^(+)(aq) + SO_(4)^(2-)(aq) to underset(O.N.=+2)underset(darr)(PbSO_(4)(s)) + 2H_(2)O(l)`
Discussion
33.

Out of `HBr` and `NaBr`, which will have greater value for `wedge_(m)^(@)` and why ?

Answer» `HBr`, because `H^(o+)` ions have greater ionic mobility than `K^(o+)` ions.
Discussion
34.

Write the formulas for the following coordination compounds: (i) Tetraammineaquachloridocobalt (III) chloride (ii) Potassium tetrahydroxozincate (II) (iii) Potassium trioxalatoaluminate (III) (iv) Dichloridobis (ethane-1, 2-diamine) cobalt (III) ion. (v) Tetracarbonylnickel (0)

Answer»

 (i) [Co(NH3)4(H2O)Cl]Cl2 

 (ii) K2 [Zn(OH)4] 

(iii) K3 [Al(C2O4)3] 

(iv) [CoCl2(en)2]+ 

 (v) [Ni(CO)4 ]
Discussion
35.

Why ac is used in place of dc in measuring the conductance of electrolytes ?

Answer» `dc` results in the electrolysis of the electrolyte.
Discussion
36.

Why lead storage can be recharged ?

Answer» `PbSO_(40` is deposited on the electrodes. So, the electrodes reactions can be reversed.
Discussion
37.

Most of the sources of energy we use represent stored solar energy which of the following is not ultimately derived from the sun’s energyA) Geothermal energyB) Wind energyC) Nuclear energyD) Bio mass

Answer»

C) Nuclear energy
Discussion
38.

Mark out the correct statement(s) regarding electrolytic molar conductivity.A. It increase as temperature increaseB. It experiences resistance due to vibration of ion at the man positionC. Increase in concentration decrease the electrolytic molar conductivity of both the strong as well as the weak electrolyteD. Greater the polarity of solvent, greater is the electrolytic molar conduction.

Answer» Correct Answer - A,C,D
`lambda_(M)=(1000K)/M T-M^(-)I_(M^(-))`
Polarity of solvent Greater : No of ions `uarr lambda_M uarr`
Discussion
39.

Why does an aqueous solution of an acid conduct electricity?

Answer»

The presence of hydrogen (H+) or hydronium (H3O+) ions in aqueous solution of an acid are responsible for conducting electricity.
Discussion
40.

Statement-1:Specific conductance decreases with dilution whereas equivalent conductance increases. Statement-2:On dilution number of ions per millilitre decreases but total number of ions increases consideably.A. Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1B. Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-2C. Statement-1 is True, Statement-2 is False.D. Statement-1 is False, Statement-2 is True.

Answer» Correct Answer - C
Total number of ions will increase slightly on dilution (Not considerably)
Discussion
41.

What is the principle of a electric motor?

Answer»

An electric motor is based on the principle that when a current is passed through conductor placed a uniformed magnetic field it experiences a force which maker the conductor rotate.
Discussion
42.

Galvanisation of iron means coating iron withA) ZincB) NickleC) ChromiumD) Tin

Answer»

The answer is A) Zinc
Discussion
43.

Statement-1:Zinc protect the iron better than tin even after it cracks. Statement-2:`E_(OP_(Zn))^@ltE_(OP_(Fe))` But `E_(OP_(Sn))^@gtE_(OP_(Fe))`A. Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1B. Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-2C. Statement-1 is True, Statement-2 is False.D. Statement-1 is False, Statement-2 is True.

Answer» Correct Answer - C
`E_(Zn^(+2)|Zn)ltE_(Fe^(+2)|Fe lt E_(Sn)^(+2)|Sn`
`SPR darr` Reactivity `uarr`
Discussion
44.

Out of `Sn` and `Zn` which one protects `Fe` better even after cracks ?

Answer» `Zn` protects better because oxidation potential of `Zn` is greater, but oxidation potential of `Sn` is less than that of `Fe`.
Discussion
45.

 Write the IUPAC name of the following coordination compounds: (i) [Co(NH3)6 ]Cl3 (ii) [Co(NH3)5Cl]Cl2 (iii) K3 [Fe(CN)6] (iv) K3 [Fe(C2O4)3] (v) [Co (en)3]Cl3

Answer»

(i) Hexaamminecobalt (III) chloride 

(ii) Pentaamminechloridocobalt (III) chloride 

(iii) Potassium hexacyanoferrate (III) 

(iv) Potassium trioxalatoferrate (III) 

(v) Tris-(ethane-1, 2-diammine) cobalt (III) chloride
Discussion
46.

 Define corrosion. What is the chemical formula of rust ?

Answer»

Corrosion is the slow eating away of the surface of the metal due to attack of atmospheric gases. Fe2 O3 -xH2 O.
Discussion
47.

Write the IUPAC names of the following coordination compounds: (i) [Pt(NH3)2Cl(NO2 )] (ii) K3[Cr(C2O4)3] (iii) [CoCl2 (en)2]Cl (iv) [Co(NH3)5 (CO3)]Cl (v) Hg[Co(SCN)4 ] 

Answer»

(i) Diamminechloridonitrito-N-platinum (II) 

(ii) Potassium trioxalatochromate (III) 

(iii) Dichloridobis (ethane-1, 2-diamine) cobalt (III) chloride. 

(iv) Pentaamminecarbonatocobalt (III) chloride 

(v) Mercury tetrathiocynatocobaltate (III) 
Discussion
48.

Considering the elements `B, C, N, F` and `Si`, the correct order of their non-metallic character is ?

Answer» c. In a period, the non-metallic character increases from left to right Thus, among `B`,`C`,`N` and `F`, non-metallic character decreases in order:`FgtNgtCgtB`. However, within a group, non-metallic character decreses from top to bottom, Thus , `C` is more non-metallic than `Si`. Therefore, the correct sequence of decreasing non-metallic character is ``FgtNgtCgtBgtSi`. i.e. option ( c ) is correct.
Discussion
49.

Considering the elements `B, Al, Mg` and `K`, the correct order of their metallic character is

Answer» d. In a period, metallic character decreases as we move from left to right. Therefore, metallic character of `K`,`Mg`, and `Al` decreases in order :`KgtMggtAl`. However, within a group, the metallic character,increases from top to bottom. Thus, `Al` is more metallic than `B`. Therefore, the correct sequence of decreasing metallic character is `KgtMggtAJgtB`, i.e. option `(d)` is correct.
Discussion
50.

What is the basic difference between the terms electron gain enthalpy and electronegativity?

Answer» Both electron gain enthalpy and `EN` refer to the tendency of the atom of an element to attract electrons. Whereas electron gain enthalpy refers to the tendency of an isolated gaseous atom to accept an additional electron to form a negatinve ion. `EN` refers to the tendency of the atom of an element in a molecule to attract the shared pair of electrons towards it in a covalent bonded molecule.
Discussion