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 do you mean by syaing that energy of the electron is quantized ?

Answer»

Solution :This MEANS that the electrons in an ATOM have only definite VALUES of ENERGIES
Discussion
2.

Why are bonding molecular orbitals more stable than anti bonding molecular orbitals?

Answer»

Solution :The bonding ORBITALS are at a lower energy than the antibonding orbitals, so they are the FIRST to FILL up. They are more stable
Discussion
3.

Which of the following compounds are formed when BCI_(3) is treated with water?

Answer»

`H_(3)BO_(3)`
`b_(2)H_(6)`
`B_(2)O_(3)`
`HBO_(2)`

SOLUTION :`BCI_(3) + 3H_(2) O to H_(3)BO_(3) + 3HCI`
Discussion
4.

Which of the following is used to produce smoke screens ?

Answer»

<P>calcium phosphide
zinc sulphide
sodium carbonate
zinc phosphide

Solution :`Ca_(3)P_(2)+6H_(2)O rarr 3Ca(OH)_(2)+2PH_(3)`
Phosphate `(PH_(3))` so formed spontaneously catches fire to give `P_(2)O_(5)`.
`2PH_(3)+4O_(2) rarr P_(2)O_(5)+3H_(2)O`
`P_(2)O_(5)` forms a white DENSE SMOKE screen.
Discussion
5.

VDs of N_(2)O_(4 (g)) at equilibrium at temperatures T_(1) & T_(2)K respectively are 40 & 30 . Ratio of total number of moles of components at equilibrium at T_(1) K to T_(2) K shall be

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`3 : 4`
`1 : 2`
`4 : 3`
`3 : 7`

ANSWER :A
Discussion
6.

what is dipolemoment

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Solution :If is the PRODUCT of the DISTANCES of CHARGE (positive or negative) CENTRES and distance between the centre.
Discussion
7.

Which one of the following is an example of disporoportionation reaction ?

Answer»

`3Cl_(2) (g) +6OH^(-) (aq) rarrClO_(3)^(-) (aq) +5CI^(-) (aq) +3H_(2)O(1)`
`Ag^(2+) (aq) +Ag (s) rarr 2Ag^(-4) (aq)`
`ZN(s) +CuSO_(4) (aq) rarr Cu(s) +ZNSO_(4)(aq)`
`2KClO_(3)(s) rarr 2KCl (s)+ 3O_(2)(g)`

Solution :`3overset(0)(Cl_(2)) (g)+6OH^(-)(aq)`
`rarr ClO_(3)^(-) (aq) +5CI^(-)(aq) +3H_(2)O(l)`
Discussion
8.

The value of planck constant is

Answer»

`6.62 xx 10^(-34)` Joule-second
`6.62 xx 10^(-27)` Joule-second
`6.62 xx 10^(-30)` Joule-second
`6.62 xx 10^(-24)` Joule-second

Answer :B
Discussion
9.

What is the coordination number of sodium in Na_(2)O ?

Answer»

6
4
8
2

Solution :In `Na_(2)O,O^(2-)`ions adopts f.c.c. LATTICE in which `NA^(+)`ions are present at all tetrahedral SITES.
`THEREFORE`Co-ordination number of `Na^(+)`ion =4
Discussion
10.

Which acid has lowest pK_(a)

Answer»

<P>`p-`Methoxybenzoic acid
`p-`Chlorobenzoic acid
`p-`Aminobenzoic acid
`p-`TOLUIC acid

Solution :Among the substituents given CHLORO group has stronger electron withdrawing EFFECT and hence is strongest acid with highest `K_(a)` and lowest `pK_(a)` VALUE respectively
Discussion
11.

Which of the following compound will not undergo nucleophilic substitution reaction ?

Answer»




ANSWER :D
Discussion
12.

The relative adsorption of each component of the mixture is expressed in terms of

Answer»

ADSORPTION FACTOR
Retardation factor
Co-factor
SORPTION factor

ANSWER :B
Discussion
13.

Which one of the following always be negative?

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1) HEAT of reaction
2) heat of solution
3) heat of combustion
4) heat of FORMATION

Answer :C
Discussion
14.

Write limitation of lewis concept and main postulates of VSEPR theory.

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SOLUTION :Lewis concept is unable to explain the shapes of molecules.
Valence SHELL electron pair repulsion theory : This theory provides a simple procedure to predict the shape of covalent molecules. Sidgwick and Powell in 1940, proposed a simpl.e theory based on the repulsive interactions of the electron pairs in the valence shell of the atoms so, its known of VSEPR theory.
The postulates of VSEPR Theory : The shape of a molecule DEPENDS upon the number of valence shell electron pairs (bonded or nonbonded) around the central atom.
pairs of electrons in the valence shell repel one another since their electron clouds are negatively charged.
These pairs of electrons tend to OCCUPY such position in space that minimise repulsion and thus maximise distance between them.
The valence shell is taken as a sphere with the electron pairs localising on the spherical surface at maximum distance from one another.
A multiple bond is treated as if it is a sing]e electron pair and the two or three electron pairs of a multiple bond are treated as a single super pair.
Where two or more resonance structures can represent a molecule, the VSEPR model is applicable to any such structure.
The repulsive INTERACTION of electron pairs decrease in the order :
[Lone pair (lp) - Lone pair (lp)] `gt`
[Lone pair (lp) - Bond pair (bp)] `gt`
[Bond pair (bp) - Bond pair (bp) ]
Discussion
15.

What is valence boned approach for the formation of covalent bond and a coordinate bond ?

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SOLUTION :A covalent bond is FORMED by the overlap of half FILLED atomic ORBITALS whereas a coordinate bond
formed by the oversap of an empty ORBITAL with a fully-filled orbital.
Discussion
16.

Which of the following has maximum number of molecules ? (C = 12, O = 16, N = 14, H = 1)

Answer»

1 mole of `H_2O` gas
32 g of CO
2.24 L of `N_2` at N.T.P.
22 g of `CO_2`

Solution :(a)`6xx10^(23)`
(B) `(6xx10^(23)xx32)/(28) = 6.86xx10^(23)`
( C) `(6xx10^(23))/(22.4) xx2.24 = 6xx10^(22)`
(d) `(6xx10^(23))/(44)xx22 = 3xx10^(23)`
CORRECT ANSWER is (b).
Discussion
17.

Write the IUPAC names of the products obtained by the ozonolysis of the following compouds :2-Ethyl but-l-ene

Answer»

SOLUTION :
Discussion
18.

What is the difference between ionic product and solubility product ?

Answer»

SOLUTION :SOLUBILITY PRODUCT is the product of the MOLAR concentrations of the IONS in a saturated solution but ionic product is for any solution.
Discussion
19.

Which hybridization is found in NH_(3) and H_(2)O?

Answer»

`SP^(3)`
`DSP^(2)`
`sp`
`sp^(2)`

ANSWER :A
Discussion
20.

Write the equations for the preparation of 1-iodobutane from: (i) 1-butanol (ii) 1-chlorobutane (iii) but-1-ene

Answer»

SOLUTION :
Discussion
21.

Write the following equation in ionic form. MnO_(2)+4HCl to MnCl_(2)+2H_(2)O+Cl_(2)

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Solution :In this REACTION HCl and `MnCl_(2)` are ionic in NATURE. Writing these comounds in ionic from,
`MnO_(2)+4H^(+)+4Cl^(-)=MN^(2+)+2Cl^(-)+2H_(2)O+Cl_(2)`
`2Cl^(-)` ION are common on both sides, so these are cancelled. The desired ionic equation reduceds, to ,
`MnO_(2)+4H^(+)+2Cl^(-)=Mn^(2+)+2H_(2)O+Cl_(2)`
Discussion
22.

Which of the following is an endothemic reaction?

Answer»

`N _(2 (g)) + 3 H _(2(g)) - 92 KJ to 2 NH _(3(g))`
`N _(2 (g)) + O _(2 (g)) + 180.8 KJ to 2 NO _((g))`
`H _(2 (g)) + Cl _(2 (g)) to 2HCl _((g) ), Delta H =- 184 . 6 KJ `
`C _(("graphite")) + 2 H _(2 (s)) to CH _(4(g)) + 74.8 KJ`

Answer :B
Discussion
23.

The reduction of 2-Butyne with H_2 in the presence of Pd/BaSO_4 - Quinoline and Na/liquid NH_3 gives

Answer»

trans-2 butene in both the CASES
cis-2-butene in both the cases
cis-2-butene and trans 2- butene
BUTANE in both the cases

Solution :It is a selective reduction and stops at alkene STAGE. First one GIVES cis-2-butene, while the second one gives trans-2-butene.
Discussion
24.

What is the hybridisation of central atom of (D)?

Answer»

`d^(2)SP^(3)`
`sp^(3)d^(2)`
`sp^(3)d`
`sp^(3)`

ANSWER :B
Discussion
25.

What is true about saline hydrides

Answer»

They are binary compounds of hydrogen and METALLIC ELEMENTS
They are CRYSTALLINE solids
They are generally very soft
Their common examples are,

Solution :According to PROPERTIES saline HYDRIDES they are binary compounds of hydrogen and metals, and they are crystalline.
Discussion
26.

What would be the SI unit for the quantity pV^(2)T^(2)//n ?

Answer»

Solution :`((N m^(-2))(m^(3))^(2)(K)^(2))/("mol")=N m^(4)K^(2)" mol"^(-1)`
Discussion
27.

Which of the following gas deviates least from ideal nature at room temperature and atmospheric pressure

Answer»

NITROGEN
METHANE
Carbon dioxide
Helium

ANSWER :D
Discussion
28.

underset([S])([M(NH_(3))_(6)]^(2+)) to underset([S])(M(NH_(2))_(2))+xunderset((g))(NH_(3))+yunderset((g))(H_(2))

Answer»


Solution :`[M(NH_(3))_(6)]^(2+) to [UNDERSET(("Solid"))(M(NH_(2))_(2))]+underset(("gas"))(4NH_(3))+underset(("gas"))(H_(2))`
`x+y=4+1=5`
Discussion
29.

Using the outcome fo previous example, arrange benzene, 1,3-cyclohexadiene, and cyclohexene in the order of decreasing rate of monohydrogenation. Strategy: Since the change in the number of moles is the same for each hydrogentaion,we assume that the DeltaS's (entropy changes) are about the same, and that the Delta_(h)H's are directly related to the DeltaH's.

Answer»

Solution :The order of chlohexene `(-120 kJmol^(-1))gt1,3-`CYCLOHEXADIENE `(-112kJmol^(-1))GT` benzene `(+24kJmol^(-1))`
Discussion
30.

The solution which consumes [H^(+)] or [OH^(-)] or both simultaneously from externally added base in order to give negligible change in pH, is known as buffer solution. In general, the solution resists the change in pH. Buffer solution does not mean that there does not occur a pH change in pH. Buffer solution des not mean that there does not occur a pH change at all. It implies the pH change occurs but in neglibible amount. There are two types of buffer (i) Acidic buffer: it is a mixture of weak acid and its salt acid strong base. (ii) Basicbuffer : It is a mixture ofweak base and its salt with strong acid. To prepare a buffer of pH 8.26, amount of (NH_(4))_(2)OH solution [pK_(a)(NH_(4^(+)) = 9.26]

Answer»

`0.05`MOL
`0.025` mol
`0.01` mol
`0.005` mol

Solution :`5.74 = 4.74 + "log" (x)/(5 xx 10^(-3))`, CALCULATING `x = 0.02`, hence `[(NH_(4))_(2)SO_(4)]` required `= 0.01`
Discussion
31.

Which one of the following indicates the correct order of atomic size? (1). C gt F gt Ne""(2) Be lt C lt F lt Ne (3). Be gt C gt F" "(4) F gt Ne gt Be gt C

Answer»


Solution :Be, C and F are the elements of same PERIOD (2ND period) hence, `Be gt C gt F.` But Ne is an INERT gas, whose Van der Waals RADII is exceptionally high, hence, `Ne gt Be gt C gt F`
Discussion
32.

When a liquid evaporates, which is true about the signs of the enthalpy and entropy changes?

Answer»

`{:(Delta H,Delta S),(+,-):}`
`{:(Delta H,Delta S),(+,+):}`
`{:(Delta H,Delta S),(-,-):}`
`{:(Delta H,Delta S),(-,+):}`

Solution :`l RARR G, Delta H GT 0, Delta S gt 0`
Discussion
33.

Write the structure of inorganic benzene ?

Answer»


ANSWER :C
Discussion
34.

Which are two isotherm graph according to Boyle.s Law.

Answer»

SOLUTION :(i) Graph p `to` V is curve.
(II) Graph of p `to(1)/(V)` is straight line PASSES through ORIGIN.
Discussion
35.

Which of the following reactions produce the same alkane as major product ?

Answer»




SOLUTION :
Discussion
36.

Which of the following is the best stereochemical representation when reaction between 1-methylcyclohexene and NBS react in aqueous dimethyl sulfoxide?

Answer»




NONE of these

Solution :NBS+aq.DMSO is USED for PREPARTION of hlohydrin.
Discussion
37.

When gypsum is heated at 393K, the compound formed is CaSO_(4).XH_(2)O value of 6X is

Answer»


Solution :`CaSO_(4)2H_(2)Ooverset(393K)(to)CaSO_(4).(1)/(2)H_(2)O+(3)/(2)H_(2)O`
`x=1//2`, `6x=6xx(1)/(2)=3`
Discussion
38.

What do you understand by the term mole?

Answer»

Solution :The mole is defined as the amount of a substance which contains 6.023* 1023 PARTICLES such as ATOMS, molecules or IONS. It is represented by the SYMBOL n.
Discussion
39.

What type of non-idealities are exhibited by cyclohexane-ethanol and acetone-chloroform mixture ? Give reason for your answer.

Answer»

Solution :Ideal SOLUTIONS are those which obey Raoult.s law over extreme range of concentration. Ideal solution have another important PROPERTIES : (i) `Delta H_(mix) =0 (ii) Delta V_(mix) =0` Here-forces of attraction between A-A, B-B and A-B are of the same order. Non ideal solutions do not obey Raoult.s law over the entire range of concentration.
`Delta H_(mix) NE 0 and Delta V _(mix) ne 0`
Cyclohexane-ethanol mixture shows POSITIVE deviation from Raoult.s law because forces of attraction between cyclohexane and ethanol are less than in between puire cyclohexane as well as pure ethanol.
Acetone-Chloroform mixture shows negative deviation from Raoult.s law because forces of attraction between acetone and chloroform are higher than that in between pure acetone and pure chloroform molecules.
Discussion
40.

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

Answer»

a. CH_3 - CH = CH_2`
B.`CH_3C -= C - CH_3`
c.`CH_3 - oversetunderset(|)(H)(C)= oversetunderset(|)(H)(C) - CH_3`
d.`CH_4`

ANSWER :B
Discussion
41.

The substance which added to the ore in order to remove impurities during smelting is called

Answer»

slag
gangue
flux
matrix

Answer :(C )
Discussion
42.

Three substances normally considered as primary pollutant are ______,______,and,____.

Answer»


ANSWER :B::C
Discussion
43.

Which of the following reactions is an example of use of water gas in the synthesis of other compounds /

Answer»

`CH_(4)(G) + H_(2)O(g) UNDERSET(Ni)overset(1270K)to CO(g) + H_(2)(g)`
`CO(g) +H_(2)O (g) underset("Catalyst")overset(673 K)to CO_(2)(g) + H_(2)(g)`
`C_(n)H_(2n+2) + H_(2)O (g) underset(Ni)overset(1270K)to nCO + (2n+1)H_(2)`
`CO(g) + 2H_(2)(g) underset("Catalyst")overset("Cobalt")to CH_(3)OH(L)`

Answer :D
Discussion
44.

When 'n' moles of CO combines with (2n+1) moles of H_2 , the hydrocarbon formed is

Answer»

ALKENE
ALKANE
Alkyne
NONE

ANSWER :B
Discussion
45.

Which of the followingg intermediates contains three paris of electrons in its valence shell?

Answer»

Carbocations
Carbanions
Free radicals
Both (a) and (B)

ANSWER :A
Discussion
46.

Which of the following statement(s) is/are correct about red vapour gas D?

Answer»

D is `CrO_(2)CI_(2)`
D gives yellow ppt. with `BA(OH)_(2)` insoluble in `CH_(3)COOH`
D is `Br_(2)`
Yellow solution of E is `Na_(2)CrO_(4)`

Solution :(A) `rarr NH_(4)CI`, (B) `rarr NH_(3),`
(C) `rarr HgO.Hg(NH_(2))I` (D) `rarr CrO_(2)CI_(2)`,
(E) `rarr Na_(2)CrO_(4)`
Discussion
47.

The solution which consumes [H^(+)] or [OH^(-)] or both simultaneously from externally added base in order to give negligible change in pH, is known as buffer solution. In general, the solution resists the change in pH. Buffer solution does not mean that there does not occur a pH change in pH. Buffer solution des not mean that there does not occur a pH change at all. It implies the pH change occurs but in neglibible amount. There are two types of buffer (i) Acidic buffer: it is a mixture of weak acid and its salt acid strong base. (ii) Basicbuffer : It is a mixture ofweak base and its salt with strong acid. Which of the following mixture will be a buffer solution when dissolved in 500 mL of water:

Answer»

`0.200` MOL of aniline and `0.200` mol of HCL
`0.200` mol of aniline and `0.400` mol of `NAOH`
`0.200` mol of NACL and `0.100` mol of `HCl`
`0.200` mol of aniline and `0.100` mol of `HCl`

Solution :For the formation of Buffer solution meq of weak base `GT` meq of strong acid.
Discussion
48.

What is called a Ideal gas ? Why ?

Answer»

Solution :A gas that follows Boyle.s law, Charle.s law and Avogadro law STRICTLY is called an ideal gas.
Such a gas is hypothetical. It is assumed that intermolecular forces are not present between the MOLECULES of an ideal gas.
When the inter molecular forces are NEGLIGIBLE in real gas it acts as an ideal gas and FOLLOW the gas rules.
Discussion
49.

The reagent used for Friedel-Craft's reaction is :

Answer»

DRY ETHER
`AlCl_3`
ANHYDROUS `AlCl_3`
`P_2O_5`

ANSWER :C
Discussion
50.

What type of substances would make better permanent magnets , ferromagnetic or ferrimagnetic ?

Answer»

Solution :FERROMAGNETIC SUBSTANCES would MAKE better permanent MAGNETS.
Discussion