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 product formed in the following reaction.

Answer»




SOLUTION :
Discussion
2.

Which of the following statements about polar stratosphere clouds (PSCs) is not correct?

Answer»

`PSCs` do not react with CHLORINE nitrate and `HCl`
Type I coluds are formed at about `-77^(@)C` and contain solid `HNO_(3).3H_(2)O`
Type II clouds are formed at about `-85^(@)C` and contain some ice
A tight WHIRLPOOL of wind called POLAR vortex is formed which surrounds Antarctica

Solution :`PSCs` react with cholrine nitrate and `HCl` to give `HOCl` and `Cl_(2)`.
Discussion
3.

Two solutions of 0.1M cr_(2) O_(7)^(2-)(aq.) and 0.1M MnI_(4)^(-) (aq.) are to be used to titatre (titrating solution) be required for a given solution of fe^(2+)(aq.) (b) If a given titration requires 24.50 mL of 0.100M Cr_(2)O_(7)^(2-) (aq.),how many mL of 0.100M MnO_(4)^(-) (aq.)would have been required if ithad been used instead?

Answer»


Answer :(a) VOL.Of `MnO_(4)^(-)` required will be `1.2` TIMES fo vol. of `Cr_(2)O_(7)^(2-)`, (b) `29.4mL`
Discussion
4.

Theunpairedelectronsin AIand sI arepresentin 3porbital. Whichelectron willexperiencemoreeffectivenuclearchargefrom thenucleus ?

Answer»

SOLUTION :Theelectronof Si has moreeffectivenuclear CHARGE.
Electroncnfigurationof AI(z=13) Ne `3s^(2) 3p^(1)`
as bothhas samevalenceshell(z=14) `Ne^(10) 3s^(2) 3p^(2)`
so nuclearchargeis more.sothere ismoreeffectivenuclear chargean si.
Discussion
5.

Which of the following pair of compounds exhibit tautomerisim?

Answer»

ETHANAL and vinyl alcohol
Methyl propyl ether and diethyl ether
Neo-pentane and n-pentane
Propanal and propanone

Solution :`{:("Ethanal",,"Vinyl alcohol"),(OVERSET(alpha)(C)H_(3)CHO,,CH_(2)=CHOH),(underset(alpha)(H)_(3)C - overset(overset(O)(||))(C )-H,hArr,H_(2)C=overset(overset(OH)(|))(C )-H),("Keto form",,"Enol form"):}`
Ethanal has `alpha`-hydrogen to CARBONYL group and it has tautomer vinyl alcohol. (B) , (C ), (D) do not have `alpha`-hydrogen to carbonyl group and their enol from
Discussion
6.

underset("Sucrose")(C_(12)H_(22)O_(11))+H_(2)Ooverset(dil." "H_(2)SO_(4))tounderset("Fructose")(C_(6)H_(12)O_(6)(aq))+underset("Glucose")(C_(6)H_(12)O_(6)(aq)) in this reaction, dilute H_(2)SO_(4) is called.

Answer»

Homogenous catalysis
Homogenous CATALYST
Heterogenous catalysis
Heterogenous catalyst

Solution :Because reactant and catalyst are PRESENT in same physical STATE.
Discussion
7.

The standard enthalpy of formation of hypothetical MgCl is -125kJ mol^(-1) and for MgCl_(2) is -642 kJ mol^(-1). What is the enthalpy of the disproportionation of MgCl ?

Answer»

`-492 KJ mol^(-1)`
`-392 kJ mol^(-1)`
`-767kJ mol^(-1)`
`-517 kJ mol^(-1)`

Solution :(i) `Mg_((s)) + Cl_(2(g)) RARR MgCl_(2(s)) , Detlta H_(1) = - 642`
(ii) `Mg_((s)) + 1//2Cl_(2(g)) rarr MgCl_((s)) , DELTA H_(2) = - 125`
(iii) `2MgCl rarr MgCl_(2) + Mg, Delta H`= ?
`Delta H = Delta H_(1)- Delta H_(2) = - 392 kJ mol^(-1)`
Discussion
8.

Which reducing agents of the following can be used for the following transformation ?

Answer»

`CH_(3) - CH = CH.COOH rarr CH_(3)CH = CH.CH_(2)OH`
`LiAlH_(4)`
`B_(2)H_(6)THF`
`H_(2)//Ni`

Solution :Equimolar quantity of unsaturated ACID and `LiAlH_(4)` reduces only `-COOH` group to `-CH_(2)OH`
Discussion
9.

What will be de-Broglie wavelength of an electron moving with a velocity of 1.2xx10^5 "ms"^(-1)

Answer»

`6.071xx10^(-9)`
`3.133xx10^(-37)`
`6.626xx10^(-9)`
`6.018xx10^(-7)`

SOLUTION :`lambda=h/p , p=mv`
`lambda=h/"mv"=(6.62xx10^(-34))/(9.1xx10^(-31)xx1.2xx10^5)`
`lambda=6.071xx10^(-9)`m
Discussion
10.

Write the expected formulas for the hydrides of 4^(th) period elements.What is the trend in the formulas? In what way the first two numbers of the series different from the others ?

Answer»

Solution :The expected formulas for the hydrides of 4th PERIOD elements MH. (electron PRECISE). M,H (electron deficient) and `MH_(3)` (electron rich). The trend in formula is
(i) Electron precise hydrides `-CH_(4)`,`C_(2)H_(6)`,`SiH_(4)`, `GėH_(4)`,
(ii) Electron deficient hydrides-`B_(2)H_(6)`
(iii) Electron rich hydrides -`NH_(3)`,`H_(2)O`.
The first two members of the series KH, Cal, are ionic hydrides WHEREAS the other members of the series `CH_(4)`, `C_(2)H_(6)`, `SiH_(4)`, `B_(2)H_(6)`, `NH_(3)` are covalent hydrides.
Discussion
11.

The Rubin number with was proposed by Ostwald as an alternative to the Gold number in order to measure the protective efficiency of a lyophillic colloid may be difined as the

Answer»

mass in milligrams of a colloid per 100 c.c. of solution which just prevent the colour change of STANDARD sol of dye Congo-Rubin FORM red to violet when 0.16 G eq. KCl is added to it.
mass in milligrams of a colloid per 100 c.c. of solution which just prevent the colour change of standard sol of dye Congo-Rubin form red to violet when 0.1 M KCl is added to it.
mass in milligrams of a colloid per 100 c.c. of solution which just prevent the colour change of standard sol of dye Congo-Rubin form red to violet when 0.2 M KCl is added to it.
mass in milligrams of a colloid per 100 c.c. of solution which just prevent the colour change of standard sol of dye Congo-Rubin form red to violet when1M KCl is added to it.

Answer :A
Discussion
12.

What is standard boiling of the liquid.

Answer»

Solution :Temperature at which vapour PRESSURE of a liquid becomes EQUAL to one bar `(10^(-5)` PA) is CALLED standard biling point of liquid.
Discussion
13.

Which of the following is used catalyst in preparation of PVC ?

Answer»

`Hg_(2)Cl_(2)`
`HgCl_(2)`
HG
`HgSO_(4)`

Answer :B
Discussion
14.

The reducing power of a metal depends on various factors. Suggest the factor which makes Li, the strongest reducing agent in aqueous solution.

Answer»

SUBLIMATION enthalpy
Ionisation enthalpy
Hydration enthalpy
Electron-gain enthalpy

Answer :C
Discussion
15.

x millimole of KlO_(3) react completely with y millimole of KI to give I_(2) quantitatively. It z millimole of hypo are required for complete titration against the I_(2) product, then

Answer»

`Z=6x`
`6y=5z`
`5x=y`
`x+y=2x`

Solution :`KIO_(3)+KIrarrI_(2)`
m eq `KIO_(3)` = m eq KI = m eq `I_(2)`
`x xx5=yxx1=nxx(5)/(3)`
`I_(2)+Na_(2)S_(2)O_(3)rarrNa_(2)S_(4)O_(6)+NaI`
m eq `I_(2)` = m eq `Na_(2)S_(2)O_(3)`
`x xx2=zxx1`
`implies x=(z)/(2)implies5x=y=(5z)/(6)`.
Discussion
16.

When metal 'M' is treated with NaOH, a whitegelatinousprecipitate 'X' is obtainedwhich issolublein excess of NaOH. Compound 'X' whenheatedstronglygives an oxide which is usedin chromatography as an adsorbent.Then metal 'M'

Answer»

Zn
Ca
`Al`
`FE`

Solution :`Al + 3 NaOH rarr 3 Na^(+) + underset(X)(Al(OH)_(3))`
`Al(OH)_(3) OVERSET(NaOH)rarr NaAl(OH)_(4)`
`2Al(OH)_(3) overset(Delta)rarr Al_(2)O_(3) + 3H_(2)O`
`Al_(2)O_(3)` is used as an adsorbent in chromatography.
Discussion
17.

When hydrogen peroxide is shaken with an acidified solution of potassium dichromate in presence of ether, the ethereal layer turns blue due to the formation of

Answer»

`Cr_(2)O_(3)`
`CrO_(4)^(2-)`
`CrO(O_(2))_(2)`
NONE of these

Solution :`Cr_(2)O_(7)^(2-)+2H^(+)+4H_(2)O_(2)to2CrO(O_(2))_(2)+5H_(2)O`
Discussion
18.

Which one is particulate pollutant ?

Answer»

`SO_x`
`NO_x`
`CO`
SMOG

Solution :Smog
Discussion
19.

Which of the following is an electrophile ?

Answer»

`CN^(-)`
`ROH`
`AICI_3`
`NH_3`

ANSWER :C
Discussion
20.

To which orbit the electron in the hydrogen atom will jump after absorbing 1.94 xx 10^(-18)J of energy ?

Answer»

Solution :Energy of electron in the nth orbit of H-atom is GIVEN by:
`E_(n) = - (21.8 xx 10^(-19))/(n^(2)) J:. E_(1) = - 21.8 xx 10^(-19) J` (`:' n = 1` for ground STATE of H-atoms)
After absorbing `1.94 xx 10^(-8) J` of energy, the energy of the electron will be
`= -21.8 xx 10^(-19) + 1.94 xx 10^(-18) J = - 2.4 xx 10^(-19) J`
Thus, `- (21.8 xx 10^(-19))/(n^(2)) = - 2.4 xx 10^(-19) or n^(2) = (21.8)/(2.4) = 9 or n = 3`
Thus, the electron will jump to the third orbit.
Discussion
21.

What are the S.I. units of suface tension ?

Answer»

SOLUTION :`NM^(-1)`
Discussion
22.

What is the maximum no. of emission lines obtained when the excited electrons of a hydrogen atom in n=5 drop to a ground state

Answer»

10
5
12
15

Solution :Number of EMISSION LINES in the spectrum will be EQUAL to `((n_2-n_1)(n_2-n_1+1))/2` where `n_2=5` and `n_1=1`
`therefore ((5-1)(5-1+1))/2 =20/2` =10 lines
Discussion
23.

Which of the following compund is achiral

Answer»




SOLUTION :(a),(B),(d) , PLANE of SYMMETRY
No plane of symmetry.
Discussion
24.

Which reactant is used to prepare trans alkene from alkyne ?

Answer»

SOLUTION :SODIUM METAL in LIQUID AMMONIA.
Discussion
25.

What type of defect can arise when a solid is heated ?Which physical property is affected by it and in what way ?

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SOLUTION :When a solid is heated, vacancy defect is produced in the crystal. This is because on heating , some ATOMS or ions LEAVE the alttice site completely, i.e, some lattice sites become vacant. As a RESULT of this defect, the DENSITY of the substance because some atoms/ions leave the crystal completely .
Discussion
26.

What happens whensodium peroxide dissolves in water?

Answer»

Solution :When sodium peroxide is DISSOLVED in water, it is READILY hydrolysed to form sodium hydroxide and water. The chemical EQUATION INVOLVED in the reaction is :
`Na_(2)O_(2(s)) +2H_(2)O_((l)) to 2NaOH_((AQ)) +H_(2)O_(2(aq))`
Discussion
27.

Which of the following is the correct orderr of acidity of carboxylic acids? (i) Cl_(3) C C OOH gt Cl_(2)CHCOOH gt ClCH_(2)COOH (ii) CH_(3)CH_(2)COOH gt (CH_(3))_(2)CHCOOH gt (CH_(3))_(3)C COOH (iii) F_(2)CHCOOH gt FCH_(2)COOH gt ClCH_(2)COOH

Answer»

(i) and (II)
(ii) and (III)
(i) and (iii)
(i), (ii) and (iii)

Solution :The strength of the ACID increases with the inductive EFFECT of the ELECTRONEGATIVE group attached to it (-I effect). The strength of the acid decreases with the presence of electron releasing group.
Discussion
28.

Which information give following figure ?

Answer»

Solution :Information-1: A and B are reactants. Its concentration is DECREASE with time and after it constant A + B `to`product.
Information-2: C and D are PRODUCTS. Initially its concentration is zero. The amount of C and D increase with time and after some time it become constant. Reactions `to`(C + D) (products)
Information-3: After some time RATE of FORWARD reaction become constant and concentration of A, B, C, D remain constant A + B `hArr` C+ D.
Discussion
29.

When organic substance undergoes degradation through bacteria , the hydrocarbon formed is

Answer»

`C_2H_4`
`C_2H_6`
`C_2H_2`
`CH_4`

ANSWER :D
Discussion
30.

Which of the following statement(s) is/are true?

Answer»

The ratio of rms speed to AVERAGE speed is independent of TEMPERATURE 
Average kinetic ENERGY is independent of the change in temperature 
The difference between rms and most probable speed increases on increase in temperature 
The rms speed is higher for He than for `H_2` at a given temperature 

SOLUTION :`(U_(rms))/(U_(av))= SQRT((3pi)/(8)) , U prop 1/(sqrtM)`
Discussion
31.

The relationship between the values of osmotic pressure of 0.1Msolutions ofKNO_3 (P_1)andCH_3 COOH(P_2)is

Answer»

` P_1 GT P_2`
` P_2 gt P_1`
` P_1 = P_2`
` (P_1)/( P_1+P_2) =( P_2)/( P_1+2P_2) `

ANSWER :A
Discussion
32.

Which ofthe following does not represent a type of crystal system

Answer»

Triclinic
Monoclinic
Rhombohedral
Isotropical

Solution :Isotropical is not a CRYSTAL SYSTEM.
Discussion
33.

When a metal rod M is dipped into an aqueous colourless concentrated solution of compound N, the solution turns light blue. Addition of aqueous NaCI to the blue solution gives a white precipitate O. Addition of aqueous NH_(3) dissolves O and gives an intense blue solution. The metal rod M is:

Answer»

`Fe`
`Cu`
`NI`
`CO`

Answer :B
Discussion
34.

When a metal rod M is dipped into an aqueous colourless concentrated solution of compound N, the solution turns light blue. Addition of aqueous NaCI to the blue solution gives a white precipitate O. Addition of aqueous NH_(3) dissolves O and gives an intense blue solution. The final solution contains:

Answer»

`[Pb(NH_(3))_(4)]^(2+)` and `[CoCI_(4)]^(2-)`
`[AI(NH_(3))_(4)]^(3+)` and `[CU(NH_(3))_(4)]^(2+)`
`[AG(NH_(3))_(2)]^(+)` and `[Cu(NH_(3))_(4)]^(2+)`
`[Ag(NH_(3))_(2)]^(+)` and `[Ni(NH_(3))_(6)]^(2+)`

Answer :C
Discussion
35.

When a metal rod M is dipped into an aqueous colourless concentrated solution of compound N, the solution turns light blue. Addition of aqueous NaCI to the blue solution gives a white precipitate O. Addition of aqueous NH_(3) dissolves O and gives an intense blue solution. The compound N is:

Answer»

`AgNO_(3)`
`ZN(NO_(3))_(2)`
`AI(NO_(3))_(3)`
`Pb(NO_(3))_(2)`

ANSWER :A
Discussion
36.

Which gases are responsible for greenhouse effect? List some of them.

Answer»

Solution :`CO_2` is mainly RESPONSIBLE for greenhouse effect. Other greenhouse gases are methane, NITROUS oxide, water VAPOURS, CFCS and ozone.
Discussion
37.

Use molecular orbitals theory to explaiin why the Be_(2) molecular does not exist .

Answer»

Solution :E.C. of `._(4) Be = 1s^(2) 2s^(2)`
M.O.E.C. of ` Be_(2) = SIGMA _(1s)^(2) sigma_(1s)^(2) sigma_(2s)^(2) sigma_(2s)^(2)`
`THEREFORE ` Bond ORDER = `(1)/(2) (4-4) = 0 `. Hence , `Be_(2)` does not exist .
Discussion
38.

What is oxidation number of N in HO_(4) ?

Answer»

Solution :By conventinal method O.N of N is : +1+4(-2)+x=0 or x =+7
this is impossible because N cannot have an O.N of more than + SINCE it has only 5 electrons in valence shell Therefore O.N of N in `HNO_(4)` must be CALCULATED by chemical bonding method the structure of `HNO_(4)`is since it contins a peroxide linkage therefore each of the two oxygen atmos of the peroxide bonds has an O.N of -1
ON of -2 thus if x is the o.n of N then +1-1-1+x-2-2=0 or x=+5
Discussion
39.

Which one of the following statement(s) is/are incorrect ?

Answer»

`KHCO_(3)` is less soluble than `NaHCO_(3)` and is thus prepared easily by FOLLOWING reaction
`NH_(4)HCO_(3) + KCl rarr NH_(4) Cl + KHCO_(3)`
`Li_(2)SO_(4)` forms double salts(alums) with `Al_(2)(SO_(4))_(3)`.
Polarising power of `Li^(+)` ion is nearly the same as that of `Mg^(2+)` ion .
Zinc displaces `H_(2)` on reaction with aq NAOH as well as with DILUTE HCl.

Answer :A::B
Discussion
40.

Value of electron gain enthalpy of 16, 17 groups are positive or negative which change is observed ?

Answer»

SOLUTION :VALUE of electron GAIN enthalpy of (16, 17 GROUPS are negative)
Discussion
41.

Which bond possess more bond length between C=C and C-=C ?

Answer»

SOLUTION :BOND LENGTH of C=C `GT` Bond length of `C-=C`.
Discussion
42.

The relationship between K_c and K_p is K_p = K_c (RT)^(Deltan) ,What would be the value of Deltan for the reaction ? NH_4Cl_((s)) hArr NH_(3(g)) + HI_((g))

Answer»

1
0.5
1.5
2

Solution :The relationship between `K_p` and `K_c` is
`K_p=K_c(RT)^(Deltan)`
Where, `Deltan` = (number of MOLES of gaseous products - (number of moles of gaseous REACTANTS)
For the reaction,`NH_4Cl_((s)) HARR NH_(3(g)) + HCl_((g))`
`Deltan`=2-0=2
Discussion
43.

Whichof thefollowingion hasthe highestnumber of theupairedelectrons ?

Answer»

`FE^(3+)`
`Fe^(2+)`
`NI^(2+)`
`CO^(2+)`

ANSWER :A
Discussion
44.

When 3.2 g sulphur is vaporised at 450^(@)C and 723 mm Hg pressure, the vapours occupy a volume of 780 mL. What is the molecular formula of S vapours ?

Answer»

`S_(2)`
`S_(4)`
`S_(6)`
`S_(8)`

Solution :(d) From ideal gas equation, `pV=(w)/(M)RT`
`THEREFORE``M=(3.2xx0.0821xx760xx1000xx723)/(723xx780)=256`
`because` 32 g of SULPHUR has 1 atom of S.
`therefore` Molecular formula=`S_(8)`
Discussion
45.

Write the generalelectronicconfigurationof s-,p-, d-, andf-block element :

Answer»

SOLUTION :(i) s- BLOCKELEMENT`: ns^(1-2) ` where n=2-7(II)p-Blockelements `: ns^(2)np^(1-6)` where n= 2-7
(iii)d- Blockelements `: (n-1) d^(1-10)ns^(0-2) ` where n=4-7
(iv) F- Blockelements `: (n-2) f^(0-14) `(n-1) `d^(0-2)ns^(2)` where n= 6-7
Discussion
46.

What is the mass percentage of Carbon in Methane (CH_(4)) (Molecular mass of CH_(4)=16)

Answer»

SOLUTION :`12/16xx100=75%` or 75%
Discussion
47.

What is the oxidation state of sulphur in (NH_(4))_(2)S_(2)O_(8) ?

Answer»

5
6
4
7

Solution :(i) `(NH_(4))_(2)S_(2)O_(8)` It has `2NH_(4)^(+)andS_(2)O_(8)^(2-)` IONS.
(ii) `S_(2)O_(8)^(2-)` has one peroxy - O - O - BOND in which two oxygen atoms are in (-1) state, Remained six .O. atoms have -2 oxidation number.
`therefore2S+2(O)+6(O)=-2`
`therefore2x+2(-1)+6(-2)=-2`
`therefore2x-2-12=-2`
`therefore2x=+12`
`thereforex=+6`

The two .O. atoms have (-1) oxidation number
Discussion
48.

What is relation between vapour pressure and temperature ? What is vapour pressure at 373 K temperature ?

Answer»

SOLUTION :Vapour PRESSURE `prop` Temperature, At 373 K or `100^(@)C` vapour pressure BECOMES 1 atm.
Discussion
49.

What is the bond order in carbon monoxide ?

Answer»


Solution :`(SIGMA1S^(2)sigma^(**)1s^(2)sigma2s^(2)sigma...2s^(2)pi2p_(X)^(2)-=pi2p_(y)^(2)sigma2p_(Z)^(2))`
Bond order = `1/2=(N_(B)-N_(a))=1/2(10-4)=3.0`
Discussion
50.

Wrtie the state of hybridisation of boron in BF_(3).

Answer»

SOLUTION :`SP^(2)`.
Discussion