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.

In the depression of freezing point experiment, it is found that

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The vapour pressure of the solution is equal to that of pure SOLVENT
The vapour pressure of the solution is more than that of pure solvent
Only SOLUTE molecules solidify at the FREEZING point
Only solvent molecules solidify at the freezing point.

Answer :D
Discussion
2.

In the dehydrohalogenation of 2-bromobutane, which conformation leads to the formation of cis-2-butene?

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ANSWER :A
Discussion
3.

In the decomposition of N_2O_5, the rate of reactionis-(d[N_2O_5])/(dt) = k [N_2O_5]. For determination of the units of k,

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UNITS of TIME are required
Units of CONCENTRATION are required
Units of both time and concentration are required
None of these

Solution :`("Conc")/("Time") = k "(Conc)"` . Hence , `k = (1)/("Time")` .
Discussion
4.

In the decomposition of hydrogen peroxide which acts as a negative catalyst?

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DILUTE ACID
Dilute acid
a (or) B
Ethanol

Solution : a (or) b
Discussion
5.

In the following sequence of reaction , "Toluene " overset(KMnO_(4)) to A overset(SOCl_(2)) to B underset(BaSO_(4))overset(H_(2)+Pd) to C. The product C is

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`C_(6)H_(5)-COOH`
`C_(6)H_(5) - CH_(3)`
`C_(6)H_(5) - CHO`
`C_(6)H_(5) - CH_(2) - OH`

Answer :C
Discussion
6.

In the decomposition of H_(2)O_(2) at a given temperature T, the energy of activation decreases from E_(1) to E_(2) by the use of a catalyst. How many times does the rate of the catalysed reaction increase?

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`(E_(1)-E_(2))`
`E_(2)/E_(1)`
`(E_(1)-E_(2))/R`
`e^((E_(1)-E_(2))//RT)`

Answer :D
Discussion
7.

In the decomposition of hydrogen peroxide acts a negative catalyst.

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`H_2S`
GLYCEROL
Pt
Fe

ANSWER :B
Discussion
8.

In the following sequence of reactions , A overset("Reduction")to B overset(HNO_2)to CH_3 CH_2 OH The compound A is

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PROPANE nitrile
Ethane nitrile
`CH_3 NO_2`
`CH_3 NC`

Solution :`underset((A))underset("ETHANENITRILE")(CH_3CN) OVERSET("REDUCTION")to underset((B))(CH_3 CH_2 CH_2) overset(HNO_2)to H_2 O + N_2 + CH_3 CH_2 OH`
Discussion
9.

In the decay process: A overset(-alpha)(to) B overset(-alpHa)(to) C overset(-beta)(to)C 1. A and B are isobars2. A and D are isotopes 3. C and D are isobars4. A and C are isobars The correct answer is :

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1 and 2
2 and 3
3 and 4
1 and 4

Answer :B
Discussion
10.

In the decomposition of H_2O_2 at 300 K, the energy of activation was found to be 18 kcal//"mol" white it decreases to 6 kcal//"mol" when the decomposition was carried out in the presence of a catalyst at 300 K.How many (Give you answer by multiplying 10^7)

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Solution :Decomposition of `H_2O_2` order (RXN)`H_2O_2toH_2OtoH_2O+1/2O_2`
Then we know `K=Ae(-EA)/(RT)`
For uncatalysed Rxn
`K_1=Ae(-Ea)/(RT) " " [T=300 K , R=2]`
`K=Ae(-18xx10^3)/(2xx300)`..(i)
and for CATALYSED Rxn `K_2=Ae(-6xx10^3)/(2xx300)`...(ii)
Equation (2)/(1)
`K_2/K_1=e((18-6)xx10^3)/(2xx300)`
`K_2/K_1=e^20`
`K_2/K_1=4.85xx10^8`
Then catalysed reaction is `4.85xx10^8` times faster than uncatalysed Rxn.
Discussion
11.

In the following sequence of reaction Toluene overset(KMnO_(4)+KOH "")(rarr)A overset(SOCl^(2) "")(rarr) B overset(H_(2)//Pd"")underset(BaSO_(4)"")(rarr)C The product C is

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`C_(6)H_(5)COOH`
`C_(6)H_(5)CH_(3)`
`C_(6)H_(5)CH_(2)-OH`
`C_(6)H_(5)CHO`

Answer :D
Discussion
12.

In the decomosition of H_(2)O_(2) at 300K, the energy of activation was found to be 18kcal/mole while it decreased to 6 kcal/mole when the decomposition was carried out in the presence of a catalyst at 300K. How many times is the catalysed reaction faster than the uncatalysed one ?

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ANSWER :`4.8xx10^(8)`
Discussion
13.

In the decay series : Aoverset(-alpha)toBoverset(-beta)toCoverset(-beta)toD

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A and B are ISOBARS
A and CARE isobars
A and D are isotopes
B and C are isotopes.

Answer :A
Discussion
14.

In the following sequence of reaction, the final product (Z) is CH-=CH underset(H_(2)SO_(4))overset(Hg^(2+))rarr X underset(H_(2)O)overset(CH_(3)MgX)rarr Y overset([O])rarr Z

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ethanol
propan-2-ol
propanone
propanol

Answer :C
Discussion
15.

In the dark brown ring test for nitrate ions

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The colour is DUE to charge transfer SPECTRA
Iron has a formal +2 oxidation STATE and NO has no charge
The complex species can be represenctedas `[Fe^(1)(H_2O)_5NO^(+)]SO_(4)`
The dark brown colour is due to `NO_2` evolved in the reaction

Solution :The colour of the brown ring is due to `E^(-)` - transfer from NO to `Fe^(2+)` and the complex is `[Fe(H_2O)_5NO] SO_4`
Discussion
16.

In the d-block, the elements which do not generally show the characteristics of transition elements include "….................., …..................." and "…...................."

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ANSWER :ZINC, CADMIUM, MERCURY
Discussion
17.

In the following sequence of reaction, the final product (Z) is CH-=CH overset(Hg^(2+))underset(H_(2)SO_(4)) to X overset(CH_(3)MgX) underset(H_(2)O) to Y overset([O]) to Z

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ethanal
PROPAN - 2 - OL
propanone
propane - 1 - ol

Solution :
Discussion
18.

In the cynamide extraction process of silver ore argentite from, name the oxidizing and reducing agents. Write the chemical equations of the reactions involved.

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SOLUTION :`4Ag+8NaCN+2H_(2)O+O_(2) to 4Na[AG(CN)_(2)]+4NaOH`
`2[Ag(CN)_(2)]^(-)(AQ)+Zn(s) to [Zn(CN)_(4)]^(2-) (aq) +2Ag(s)`
(i) OXIDISING agent `-O_(2)` (ii) Reducing agent =Zn
Discussion
19.

In the cyanide solution acts as a:

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PRESENCE of `O_(2)` is required to OXIDISE `Na_(2)` into `Na_(2)SO_(4)`.
Hybridisation of X is `sp^(2)`.
COMPLEX X is linear in shape.
Reaction is a typw of Hydrometallurgy.

Answer :B
Discussion
20.

In the cyanide process for the extraction of silver, sodium cyanide is used to

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CONVERT SILVER into a SOLUBLE silver complex
Reduce silver
Precipitate silver
Oxidise silver

Answer :A
Discussion
21.

In the cyanide process for extraction of gold and silver from ores, the cyanide solution acts as a………

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leaching agent to bring ores into solution. 
leaching agent to dissolve all other constituents of ores leaving the GOLD and silver as mtals. 
leaching agent to bring the gold and silver into solution as CYANIDE COMPEXES and thus seperate these metals from the ores. 
reducing agent to REDUCE the gold and silver COMPOUNDS present in the ores into the metallic states. 

Answer :C
Discussion
22.

In the cyanide extraction process of silver from argentite ore, the oxidising and reducing agents used as

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`O_(2) and CO` respectively
`O_(2) and ZN` dust respetively
`HNO_(3)` and Zn dust respectivey
`HNO_(3) and CO` respectively

Solution :In the cyanide extraction process of silver from argentite ore, the OXIDISING and reducing AGENT are `O_(2) and Zn` dust.
Discussion
23.

Inthecyanideextraction processof silverfrom argentiteore,the oxidisingandreducing agentsusedare

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` O_ 2andCO`RESPECTIVELY
` O_ 2and ZN `dustrespectively
` HNO_3 andZn `dust respectively.
` HNO _ 3and CO`respectively.

Solution : ` O_ 2`oxidises`Na_ 2 S `formedinthereactionto` Na_2 SO_ 4`and Znreduces` Ag^(+) ` to metallicAg.
Discussion
24.

In the cup and cone arrangement of blast furnace, the cone enables __________.

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INTRODUCTION of pre-heated AIR into the furnace
prevention of LOSS of gases
uniform ditribution of charge
removal of MOLTEN slag

Answer :C
Discussion
25.

In the following sequence of reaction, the end product is : HC equiv CH overset(Hg^2+)underset(H_2SO_4) rarrA overset(CH_3MgX)underset(H_2O)rarrB overset(O)rarr C

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Acetaldehyde
Isopropyl alcohol
Acetone
Ethyl alcohol

Answer :C
Discussion
26.

In the following sequence of reaction product ' C' is H- CHO + CH_(3) -CH_(2)-CH_(2) -MgXoverset((i) "dry ether " ) underset((ii) H_(3) O^(+) ) (rarr)A overset(conc. H_(2) CO_(4) " ")(rarr) B overset ((i)B_(2)H_(6)//THF)underset((ii) H_(2)O_(2) // OH)(rarr)C

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`Ch_(3)-CH=CH-CH_(3)`
`CH_(3) - CH_(2) -CH_(2)- CH_(2)-OH`
`CH_(3) - UNDERSET(underset("OH")(|))(C)H -CH_(2)- CH_(3)`
`CH_(3) - CH_(2) -CH_(2)- CHO`

ANSWER :B
Discussion
27.

In the cubic close packing, the unit cell has

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4 TETRAHEDRAL VOIDS each of which is shared by four ADJACENT unit cells. 
4 tetrahedral voids within the unit cell. 
8 tetrahedral voids each of the which is shared by four adjacent unit cells. 
8 tetrahedral voids within the unit cells. 

SOLUTION :NUMBER of atoms per unit cell = 4
`therefore` Number of tetrahedral voids = 8 
Discussion
28.

In the crystalline solids the smallest repeating part in the lattice is known as unit cell. The unit cells are described as simple (points at all corners), body centred (points at all the corners and it the centre), face centred (points at all the corners and centre of all faces), and end centred (points at all hte corners and centres of two opposite and faces) unit cells. In two common tyupes of packing ccp and hcp, 26% of space is left unoccupied in the form of interstitial sites. For the stable ionic crystalline structures, there is difinite radius ratio limit for a cation to fit perfectly in the lattice of anions, called radius ratio rule. This also defines the coordination number of an ion, which is the number of nearest neighbours of opposite charges. This depeds upon the ratio of radii of two types of ions, r_(+)//r_(-). This ratio for coordination numbers 3,4,6,and 8 is respectively 0.155 - 0.225, 0.225 - 0.414, 0.414 - 0.732 and 0.732 - 1 respectively. A face centred lattice a metal M and a body centred cubic lattice of metal N contain same number of 2.25 xx 10^(22) unit cells. If density of M is twice than that of N, the ratio between the number of atoms per unit cell is

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`4 :1`
`1 : 1`
`2 : 1`
`1 : 4`

Solution :fcc arrangment has 4 atoms per unit cell while BCC arrangment has 2 atoms per unit cell. Therefore, ratio between atoms is 4: 2 or 2 : 1. Here density does not MAKE any DIFFERENCE.
Discussion
29.

In the crystals of which of the following ionic compounds would you expect maximum distance between the centres of the cations and anion

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LIF
CSF
CSI
liI

Answer :C
Discussion
30.

In the following sequence of reaction, the end product is, CH_3CHOoverset (HCN) rarr Aoverset (H_2O)rarrB

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`CH_3COOH`
`CH_3CHOHCOOH`
`CH_3CH_2NH_2`
`CH_3CONH_2`

ANSWER :B
Discussion
31.

In the crystal structure of metallic Zn, the layers of Zn atoms have stacking sequence ABABAB… . What type of close-packed structure is formed in the crystal of Zn? How many Zn atoms are there in the unit cell of Zn crystal?

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SOLUTION :In three dimensions, the close-packed STRUCTURE with stacking SEQUENCE ABABAB… is CALLED a hexagonal close-packed structure. The unit CELL in the close-packed structure is hexagonal unit cell. This unit cell contains 6 atoms. Hence, the number of Zn atoms per unit cell in Zn crystal is 6.
Discussion
32.

In the crystalline solid MSO_(4).nH_(2)Oof molar mass 250 g mol^(-1), the percentage of anhydrous salt is 64 by weight. The value of n is

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2
3
5
7

Solution :Mass of anhydrous `MSO_(4)` salt `=64/100 xx 250 = 160` g/mole
TOTAL mass of `H_(2)O` in `MSO_(4).nH_(2)O = 250-160 = 90` g/mole
Therefore, the value of N `=90/18 =5`
Discussion
33.

In the following sequence of reaction how many nucleophilic substitution taking place.

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SOLUTION :
Discussion
34.

In the crystalA^(2+)B^(2-),having anions in the face-centred cubicpacking if the radius of the anion is 1.84 Åideal radius of thecationpresent in the tetrahedral hole will be

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`0.225 Å`
`0.414 Å`
`0.732 Å`
none of these

SOLUTION :RADIUS of tetrahedral HOLE`=0.225xx`R
`=0.225xx1.84 Å =0.414 Å`.
Discussion
35.

In the course of chemical reaction, an oxidant

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GAINS electron
Either of these
Loose electron
None

Answer :A
Discussion
36.

In the following sequence of reaction :CH_3CH_2CH_2I overset(KOH(alc.))rarr(A) overset(HBr)rarr(B) overset(KOH(aq.))rarr [C] .C is:

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Propene
propyne
Propan-1-ol
Propane-2-ol

Answer :D
Discussion
37.

In the corrections made in the ideal gas equation for real pases, the reduction in pressure due to attractive forces is directly proportional to

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`(N)/( V )`
nb
`(n^(2))/( V^(2) b)`
`(n^(2))/( V^(2))`

Answer :D
Discussion
38.

In the coordination compound ,Na_(2)[Pt(CN)_(4)] the Lewis acids is

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`[Pt(CN)_(4)]^(2-)`
`Na^(+)`
`Pt^(2+)`
`CN^(-)`

Answer :C
Discussion
39.

In the following sequence of reaction : CH_3CH_2CH_2I overset(KOH(alc.))rarr(A) overset(Br_2)rarr(B) overset(NaNH_2)underset(NH_3)rarr [C] : The end product Cis :

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Alkene
alkanol
Alkyne
Alkyl amine

Answer :C
Discussion
40.

In the coordination entity [Fe(CN)_(6)]^(4-) the oxidation state of iron is represented as………. .

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ANSWER :II
Discussion
41.

In the following sequence of reaction CH_(3)CH_(2) OH overset(P + I_(2)) to A overset(Mg) underset("ether") to B overset(HCHO) to C overset(H_(2)O) to D Find the number of -OH group in compound D.

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SOLUTION :`CH_(3)CH_(2)OH overset(P + I_(2)) to underset([A])(CH_(3)CH_(2)I) to underset("Ether")overset(Mg) to underset(B)(CH_(3)CH_(2)MGI) overset(HCHO)to underset( C) (H-underset( C)underset(H)underset(|)overset(CH_(2)CH_(3))C-OMgI overset(H_(2)O) to underset("n-propylalcohol")underset(D)underset(H)underset(|)overset(CH_(2)CH_(3))overset(|)C-OH`
Discussion
42.

In the coordination compound K_(4)[Ni(CN)_(4)], the oxidation state of nickel is :

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`-1`
0
`+1`
`+2`

SOLUTION :`overset(+4)K_(4)[overset(0)NI(overset(-4)CN)_(4)]`
Discussion
43.

In the following sequence of reaction CH_(3) - CH_(2) - OH overset(PH_(v))(to) A underset("ether")overset(Mg)(to) B overset(HCHO)(to) C overset(H_(2)O)(to) D The product D is:

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n-butylalcohol
n-propylalcohol
propanal
butanal

Answer :B
Discussion
44.

In the following sequence of the reactions : CH_(3)CH_(2)CH_(2)I overset(KOH(Alc.))rarr A overset((i) Br_(2))underset((ii) alc. KOH)rarr B overset(Na//NH_(3))rarr C The end product C is :

Answer»

alkene
alkanol
alkyne
alkylamine

Answer :C
Discussion
45.

In the conversion of starch to ethyl alcohol, the following enzymes are used

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INVERTASE, ZYMASE, Emulsin
MALTASE, Zymase, Emulsin
DIASTASE, Maltase, Zymase
Invertase, Diastase, Zymase.

Answer :C
Discussion
46.

In the following sequence fo reaction end product is . CH -= CH overset(Hg^(+)//H_(2)SO_(4))to B overset([O]) to C overset(Ca) to D overset("dry distillati on ") to E

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ACETALDEHYDE
PROPANONE
METHANAL
ethanoic ACID

Answer :B
Discussion
47.

In the conversion of I_2 rarr IO_3^-the oxidation state of iodine changes from

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0 to +6
0 to +5
0 to -1
0 to -3

Answer :B
Discussion
48.

In the conversion of K_2Cr_2O_7 to K_2CrO_4 the oxidation number of chormium :

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Increases
Romains the same
Decreases
None of these

Answer :B
Discussion
49.

In the following sequence of reactions, CH_(3)CH_(2)CH_(2)Br overset("KOH"(Alc))(rarr) " (A) " overset("HBr")(rarr) " (B) " overset("KOH"(aq))(rarr) (C )The product (C) is

Answer»

propene
propyne
propan-1-ol
propan-2-ol

Answer :D
Discussion
50.

In the conversion of Br_2 to BrO_3^-,the oxidation state of bromine changes from :

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`0` to `+5`
`-1` to `5`
`0` to `-3`
`+2` to `+5`

ANSWER :A
Discussion