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.

If a unimolecular reaction, A(g) toProducts, takes place according to the mechanism (I) A+Aoverset(k_(1))underset(k_(-1))(hArr)A^(a)+A (II) A^(a)underset(k_(2))(to)P where k_(1), k_(-1) and k_(2) are the rate constants and P, A and A^(a) stand for product molecule, normal molecule of reactant and activated molecules of reactant and activated molecules of reactant respectively. Which of the following expressions are correct?

Answer»

`(d[A^(a)])/(dt)=k_(1)[A]^(2)-k_(-1)[A^(a)][A]-k_(2)[A^(a)]`
`(d[A^(a)])/(dt)=0`
`[A^(a)]=(k_(1)[A]^(2))/(k_(-1)[A]+k_(2))`
All of the above

Answer :D
Discussion
2.

If a thin slice of sugar beet is placed in concentrated solution of NaCl then:

Answer»

Sugar beet will lose WATER from its cells
Suagar beet will ABSORB water from solution
Sugar beet will NEITHER absorb nor lose water
Sugar beet will DISSOLVE in solution

Answer :A
Discussion
3.

If a system consists of a number of phases, it is said to be ……………… .

Answer»

SOLUTION :HETEROGENEOUS
Discussion
4.

If a substance with half life 3 days is taken at other place in 12 days.What amount of substance is -left now…..

Answer»

`1//4`
`1//8`
`1//16`
`1//32`

ANSWER :C
Discussion
5.

If a substance with half life 3 days is taken at other place in 12 days . What amount of substance is left now

Answer»

`1//4`
`1//8`
`1//16`
`1//32`

Solution :T = `t_(1//2) xx N` i.e. 12 = `3 xx n implies n = 4`
`N = N_(0) ((1)/(2)) ^(n) implies (N)/(N_(0)) = ((1)/(2))^(4) = (1)/(16)`.
Discussion
6.

If a substance with half life 3 days is taken at other place in 12 days. What amount of substance is left now, if it follows first order kinetics

Answer»

`(1)/(32)`
`(1)/(8)`
`(1)/(16)`
`(1)/(4)`

ANSWER :C
Discussion
7.

If a strip of gold metal is placed ina solution of ferrous sulphate

Answer»

Gold will precipitate out
Iron will precipitate out
Gold and iron both will be dissolved
no reaction will take PLACE

Solution :Au is LESS reactive than FE .
Discussion
8.

If a strip of Cu metal is placed in a solution of ferrous sulphate

Answer»

Copper will PRECIPITATE out
Iron will precipitate out
Copper will dissolve
No reaction will take place

Solution :`Cu+FeSO_(4)to`No reaction because Cu has `E^(@)=0.34` volt and Fe has `E^(@)=-0.44`volt.
Discussion
9.

If a strip of copper metal is placed in a solution of ferrous sulphate:

Answer»

Copper will PRECIPITATE out
IRON will precipitate out
Both copper and iron will be dissolved
No REACTION will take place

Answer :D
Discussion
10.

If 'a' stands for the edge length of the cubic systems: simple cubic, body centered cubic and face centred cubic, then the ratio of radii of the spheres in these systems will be respectively. 2.

Answer»

`1/2 a:SQRT(3A):(1)/sqrt(2)a`
`1/2 a:sqrt(3a)/(2)a:sqrt(2)/sqrt(2)a`
`1/2 a:sqrt(3a):sqrt(2)a`
`1/2 a:sqrt(3a)/(4):(1)/(2sqrt(2))a`

Answer :D
Discussion
11.

If 'a' stands for the edge length of the cubic system : simple cubic , body centred cubic and face centred cubic, then the ration of the radii of the spheres in these systems will be respectively :

Answer»

`(1)/(2)a : ( sqrt(3))/( 4) a : ( 1)/( 2 sqrt(2)) a`
`(1)/(2)a :sqrt(3) a : ( 1)/(sqrt(2)) a`
`(1)/(2)a : ( sqrt(3))/( 2) a : ( sqrt(2))/( 2) a `
`1a : sqrt(3) a : sqrt(2) a `

Solution :For simple cubic, `a = 2r :. R = ( a)/( 2)`
for BCC, `4r = sqrt( 3) a :.r= ( sqrt(3)a)/( 4)`
for fcc, `4r = sqrt(2)a :.r=(sqrt(2)a)/(4)`
RATION is `: ( a)/(2) : ( sqrt(3)a)/( 4) : ( sqrt( 2) a )/( 4)`
or `( 1)/(2) a : ( sqrt( 3) )/(4) a : ( 1)/( 2 sqrt( 2)) a `
Discussion
12.

If 'a' stands for the edge length of the cubic system, sc,bcc,and fcc. Then the ratioof radii of spheres in these system will be respectively.

Answer»

`(1/2a : (sqrt3)/2 : (SQRT2)/2 a)`
`(SQRT(1)a : sqrt(3)a : sqrt(2)a)`
`(1/2a : (sqrt3)/4 a : 1/(2sqrt2)a)`
`(1/2 a : sqrt(3)a : 1/(sqrt2)a)`

SOLUTION :`sc IMPLIES 2r = a implies r = a/2`
`bcc implies 4r = sqrt(3)a implies r = (sqrt(3)a)/(4)`
`fcc implies 4p = sqrt(2)a implies r = (sqrt(2)a)/4 = a/(2sqrt(2))`
`(a/2):((sqrt(3)a)/(4)) : (a/(2sqrt(2)))`
Discussion
13.

If 'a' stands for the edge length of the cubic system , sc, bcc, and fcc. Then the ratio of radii of spheres in these systems will be respectively.

Answer»

`((1)/(2)a:(SQRT3)/(2)a:(sqrt2)/(2)a)`
`(sqrt1a:sqrt3a:sqrt2a)`
`((1)/(2)a:(sqrt3)/(4)a:(1)/(2SQRT2)a)`
`((1)/(2)a:sqrt3a:(1)/(sqrt2)a)`

Solution :Hint : `sc rArr 2r = a rArr r=(a)/(2)`
`BC crArr 4r = sqrt3arArr r=(sqrt3a)/(4)`
`FCC rArr 4r = sqrt2a rArr r=(sqrt2a)/(4)=(a)/(2sqrt2)`
`((a)/(2)):((sqrt3a)/(4)):((a)/(2sqrt2))`
Discussion
14.

If a solution is prepared by adding common salt to pure water, which of the following statements is true ?

Answer»

Both FREEZING POINT and BOILING point of solution will decreases.
The freezing point of solution will INCREASE but boiling point will decrease.
Both freezing point and boiling point of solution will increase.
The freezing point of solution will decrease but boiling point will increase.

Answer :D
Discussion
15.

If a solution is described as 10% glucose in water by mass, it means that 10 g of glucose is dissolved in 100 g water.

Answer»

SOLUTION :FALSE, 10 G in 90 g of water
Discussion
16.

If a solution has a pH of 7.41, determine its H+ concentration.

Answer»

SOLUTION :`PH=-log[H^(+)]`
`therefore [H^(+)]=" antilong "[-pH]j="ANTILOG "[-7.41]`
`therefore""[H^(+)]=3.9xx10^(-8)M`
Discussion
17.

If a refrigerator's door is opened , then we get

Answer»

Room heated
Room cooled
More amount of heat is passed out
No EFFECT on room

Solution :The compressor has to RUN for longer TIME RELEASING more heat to the surroundings.
Discussion
18.

If a solution has apH of 7.41, determine its H^+ concentration.

Answer»

Solution :`PH=-log[H^(+)]`
`therefore [H^(+)]=" antilong "[-pH]j="antilog "[-7.41]`
`therefore""[H^(+)]=3.9xx10^(-8)M`
Discussion
19.

If a refrigerator's door is opened, the we get

Answer»

ROOM HEATED
room COOLED
more AMOUNT of the gas in the refrigerator
no effect on room.

Answer :A
Discussion
20.

If a small Cu rod is placed in an aqueous solution of ferrous salt, then which of the following will be observed? (E_((Cu^(2-)) /(Cu))^0 = -0.34 V,E_((Fe^(2+)) /(Fe))^0 = -0.44 V)

Answer»

COPPER will be oxidised
`Fe^(2+)` will be reduced
No reaction will TAKE place
`Fe^(2+)`will be oxidised

Answer :C
Discussion
21.

If a sample of pure SO_(4) gas is heated to 600^(@)C, it dissociates into SO_(2) and O_(2) gases upto 50% .What is the average molar mass of the final sample.

Answer»


ANSWER :64 GM
Discussion
22.

If a salt bridge is removed between the two half cells in an experiment , the voltage

Answer»

does not change
increases rapidly
decreases slowly
falls to zero

Answer :D
Discussion
23.

If a salt bridge is removed from the two half cell, the voltage:

Answer»

DROPS to zero
Does not change
Increases gradually
Increases rapidly

Answer :A
Discussion
24.

if a refrigerator's door is kept opend, then we get a

Answer»

room cooled
room HEATED
more heat is passed out
no EFFECT on room

Solution :the room GETS heated because heat is RELEASED to the surroundings.
Discussion
25.

Ifa rocketwasfuelled withKerosene andliquid oxygen, whatmassofoxygenwouldberequirdevery litre of kerosene ? (assumekeroseneto haveaveragecompostionC_(14)H_)30). thedensityof ker soneis0.764 g,/mL )

Answer»

Solution :`underset(198 g) (C_(14))H_(30)+(43)/(2)underset(688g)(O_(2))to 14CO_(2)+_15H_(2)O`
Discussion
26.

If a salt bridge is removed between the half cells, the voltage:

Answer»

DROPS to zero
does not change
increase gradually
increases rapidly

Answer :A
Discussion
27.

If a salt bridge is removed between the half cells, the voltage

Answer»

DROPS to zero
does not change
increase gradually
increases rapidly

Answer :A
Discussion
28.

If a refrigerator's door is opened then, we get

Answer»

room heated
room cooled
more AMOUNT of HEAT is passed out
no effect on room

Solution :In such a conditions, the COMPRESSOR has to run ffor LONGER time, RELEASING more heat to the surroudings.
Discussion
29.

If a refrigerator door is opend then we get

Answer»

ROOM cooled
Room heated
more HEAT is PASSED out
no EFFECT on room

Answer :B
Discussion
30.

If a reaction with t_(1//2)=69.3 sec, has a rate constant 10^(-2)sec^(-1), the order is

Answer»

`0`
`1`
`2`
`3`

Answer :B
Discussion
31.

If a reaction with t_1//_2=69.3 second, has a rate constant 10^-2 per second, the order is:

Answer»

ZERO
1
2
3

Answer :B
Discussion
32.

If a reaction obeys the following equation k-2.303/t"log"a/(a-x) the order of the reaction will be

Answer»

ZERO
one
two
three

Answer :B
Discussion
33.

If a reaction obeys the following equation K = (2.303)/t log a/(a - x) then the order reaction is

Answer»

0
1
2
3

Solution :RATE EXPRESSION for first order is `K = (2.303)/t log a/(a - X)`
Discussion
34.

If a reaction A +B toC is exothermic to the extent of 30 kJ/mol and the forward reaction has an activation energy of 70 kJ/mol, the activation energy for the reverse reaction is

Answer»

30 kJ/mol
40 kJ/mol
70 kJ/mol
100 kJ/mol

Solution :
Discussion
35.

If a reaction A+BtoC is exothermic to the extent of 30 KJ/mol and the forward reaction has an activation energy of 70 KJ/mol, the activation energy for the reverse reaction is

Answer»

30 KJ/mol
40KJ/mol
70KJ/mol
100KJ/mol

Solution :`A+BtoC+30,DeltaH=A.E.(F)-A.E(B)-30=70-A.E(b),A.E.(b)=100`
Discussion
36.

If a reaction , A+B to C , is exothermic to the extent of 30kJ//mol and the forward reaction has an activation energy 70kJ//mol, the activation energy for the reverse reaction is

Answer»

`30kJ//mol`
`40kJ//mol`
`70kJ//mol`
`100kJ//mol`

SOLUTION :
Activation ENERGY for BACKWARD reaction `=100kJ`
Discussion
37.

If a radioactive nucleide of group 15 element undergoes Beta-particle emission, the daughter element will be found in :

Answer»

16 group
14 group
13 group
same group

Answer :A
Discussion
38.

If a radioactive isotope with atomic number A and mass number M emits an alpha-particle, the atomic number and mass number of that new isotope will become

Answer»

`A -2, M -4`
`A -2, M`
`A, M -2`
`A -4, M -2`

Solution :`._(A)X^(M) OVERSET(-alpha)RARR ._(A-2)Y^(M-4)`
Discussion
39.

If a pure enantiomer of 1,3-dichloropentane shown below is subject to free radical chlorination to obtain trichloropentane how many different isomers would be formed ?

Answer»

7
5
3
9

Solution :
Discussion
40.

If a radioactive element is placed in an evacuated container, its rate of disintegration will :

Answer»

be increased
be decreased
change only slightly
remain UNCHANGED.

ANSWER :D
Discussion
41.

If a process is both endothermic and spontaneous, then

Answer»

`Delta S GT 0`
`Delta S lt 0`
`Delta H lt 0`
`Delta G gt 0`

SOLUTION :`Delta S gt 0`
Discussion
42.

If a portion of DNA code is CAT, the anticodon for this code in on t RNA will be

Answer»

GUA
GTA
ATG
AUG

Answer :A
Discussion
43.

If a polythene sample contains two monodisperse fractions in the ratio 2 : 3 with degree of polymerization 100 and 200, respectively, then its weight average molecular weight will be:

Answer»

4900
4600
4300
5200

Solution :4900
Discussion
44.

If a person is injured by the shot of a gun and all the pellets could not be removed, it may cause poisoning by:

Answer»

Hg
Pb
Fe
Ae

Answer :B
Discussion
45.

If a non-volatile solute is dissolved in a volatile solvent relative lowering of vapour pressure is equal to

Answer»

MOLES of SOLUTE
Moles of solvent
Mole FRACTION of solute
Mole fraction of solvent

Answer :C
Discussion
46.

If a non-metal is added to the interstitial sites of a metal then the metal becomes:

Answer»

Softer
Less malleable
Less tensile
More ductile

Answer :B
Discussion
47.

If a noble gas emits one alpha-particle then it will be shifted in group

Answer»

2
3
16
17

Solution :Noble GASES are group 18 elements. Emission of `ALPHA`-particles from the NUCLIDE of noble gas will DISPLACE the daughter nuclide two places left to the parent nuclide that means it will be shifted in group 16
Discussion
48.

If a molecule contains one carbon atom carrying four different groups it will not have a plane of symmetry and must therefore be chiral. A carbon atom carrying four different groups is a steregoenic or chiral centre. A structure with a plane of symmetry is achiral and superimposable on its mirror image and cannot exist as two enantiomer. A structure without a plane of symmetry is chiral and not superimposable on its mirror image and can exist as two enantiomer. Compound has both center of symmetry and P.O.S

Answer»




ANSWER :D
Discussion
49.

If a mole was to contain 1.0xx10^(24) particles, the mass of one mole of oxygen is:

Answer»

53.2g
5.32g
32.0g
16.0g

Answer :A
Discussion
50.

If a mole of H_(2) molecule is heated to high temperature the following reaction takes place

Answer»

`H_(2)(G)+436kJ =H(g)+H(g)`
`H_(2)(g)+820 kJ=2H_(2)(g)`
`2H_(2)(g)+436 J = 2H_(2)`
`H_(2)+H_(2)=H^(+)+H^(+)`

ANSWER :A
Discussion