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 formula of diborane ?

Answer»

SOLUTION :`B_2 H_6`
Discussion
2.

Thermite is a mixture of x parts of Fe_(2)O_(3) and y parts of aluminium powder, x, y respectively are

Answer»

3, 1
3, 2
1, 1
2, 3

Solution :3 : 1 ratio of `Fe_(2)O_(3)` and .Al. powder.
Discussion
3.

What is the basicity of hypohosphours acid ?

Answer»


Solution :`H_(3)PO_(2)` has only ONE replaceable H, i.e., OH group and hence its basicity is 1.
Discussion
4.

What type of bondis formed between K^(+) " and "Cl^(-) ?Explain the bond formation .

Answer»

SOLUTION :Ionic bond is formed between `K^(+)" and "Cl^(-)` When the electronegativity difference between the two combining atoms is large , the least electrongegative atom completely transfers one or more of its valence electrons to the other combining atom so that both atoms can ATTAIN the nearest inert gas electronic configuration. The complete transfer of electron leads to the formation of a cation and an anion . Both these ions are held together by the electrostatic attractive force which is known as ionic bond.
Let us consider the formation potassium chloride . The electronic configuration of potassium and chlorine are
Potassium (K) : [Ar] `4s^(1)`
Chlorine `(Cl): [Ne]3s^(2),3p^(5)`
Potassiumhas one electron in its valence shell and chlorine has seven electron in its valence shell . By loosing one electron potassium attains the inert gas electronic configuration of argon andbecomes a unpositive cation `(K^(+))` and chlorine accepts this electron to become unnegative chloride ion `(Cl^(-))` there by attaining the stable electronicconguration of argon. These two ions combine to FORM an ionic crystal in which they are held together by electrostatic attractive force . The energy required for the formation of one mole of `K^(+)` is `418.81` KJ ( ionization energy) and the energy released during the formation of one mole of `Cl^(-)` is `-348.56` kJ ( electron gain enthalpy) .The sum of these two energies is positive `(70.25 kJ)` . However , during the formation of one mole potassium chloride crystal from its constituent inos, 718 kJ energy is released.This favours the formation of KCl and it stabilises.
Discussion
5.

What is the composition of water gas?

Answer»


ANSWER :`CO+H_(2)`
Discussion
6.

What is correct order of electrophillic addition of following alkene?

Answer»

II gt IV gt I gt III
IV gt III gt II gt I
III gt I gt IV gt II
I gt II gt III gt IV

Solution :Electron RELEASING GROUP and stability of carbocation/halonium ION will decide rate of reaction in electrophilic ADDITION reaction.
Discussion
7.

White metal is an alloy of

Answer»

`NA, MG`
`Na, PB`
`LI, Mg`
`Li, Pb`

ANSWER :D
Discussion
8.

Which mechanism has different reactivity order of alkyl halides (1^@,2^@,3^@) than others :

Answer»

`S_N1`
`S_N2`
E1
E2

Answer :B
Discussion
9.

Water can be lifted into the water tank at the top of the house with thehelp of a pump . Then why is not considered to be spontaneous ?

Answer»

Solution :A SPONTANEOUS PROCESS shouldcontinuetaking place by itself after initiation . Bt this is not so in the givencase because WATER will go up so long as the PUMP is working.
Discussion
10.

Which of the following would produce effervesence with sodium bicarbonate ?

Answer»




All of these

Solution :All acids which are STRONGER than CARBONIC acid will PRODUCES effervesence with SODIUM BICARBONATE
Discussion
11.

Which contain maximum atomic radius between metal , non - metal and noble gas.

Answer»

Solution :NOBLE gas having maximum atomic RADIUS because their OCTATE completed so attraction is not observed in noble gas than compare to covalent radius and METALLIC radius.
Discussion
12.

Which of the following is a non-aqueous solution ?

Answer»

Salt solution
Sugar solution
`Br_(2)` in `CCl_(4)`
ETHANOL DISSOLVED in water

Answer :C
Discussion
13.

which of the structural isomeric ketones having molecular formula (C_(5)H_(10)O) give iodoform test ?

Answer»

Phenol gives POSITIVE bromine water test
ANILINE gives foul SMELLING compound on reaction with `CHCl_(3)+KOH`
Formic ACID gives positive Tollen's test
NITROBENZENE gives positive Tollen's test

Solution :Nitrobenzene does not give positive Tollen's test.
Discussion
14.

Which of the following statements concer ning light is false ?

Answer»

It is a form of energy 
It cannot be deflectedby a MAGNET 
It consists of PHOTONS of same enrgy 
It is a part of electromagnetic SPECTRUM 

ANSWER :C
Discussion
15.

Which of the following groups contain only electrophiles ?

Answer»

`BF_(3) , NH_(3), H_(2) O`
`AICI_(3), SO_(3) , NO_(2)^(+)`
`NO_(2)^(+), CH_(3)^(+), CH_(3) - C = O`
`C_(2) H_(5)^(-) , C_(2) H_(5) , C_(2) H_(5)^(+)`

Answer :B::C
Discussion
16.

Which of the following will have the most negative electron gain enthalpy and which the least negative ? P, S, CI, F.

Answer»

Solution :Electron gain ENTHALPY generally becomes more negative across a period as we move from left to right. Within a group, electron gain enthalpy becomes less negative down a group. HOWEVER, adding an electron to the 2p-orbital leads to GREATER repulsion than adding an electron to the larger 3p-orbital. Hence the element with most negative electron gain enthalpy is chlorine, the one with the LEAST negative electron gain enthalpy is phosphorus.
Discussion
17.

Whichorbitalis nondirectional ?

Answer»

4P
4d
4f
3s

Answer :D
Discussion
18.

Which of the following chlorides are soluble in pyridine ?

Answer»

LiCl
CsCl
NACL
`BeCl_(2)`

Solution :Being COVALENT LiCl and `BeCl_(2)` are soluble in pyridine .
Discussion
19.

Write electron order in the following compound,

Answer»


Answer :(a) `I gt II gt III gt IV`(B) `III gt I gt II gt IV`
Discussion
20.

Which one of the following is not an electrophile?

Answer»

`RNH_(2)`
ROR
`R-OH`
All

Answer :D
Discussion
21.

Which are the acids of this reaction ? HCl_((aq)) +H_2O_((aq)) hArr H_3O_((aq))^(+) + Cl_((aq))^(-) Which acid is strong ?

Answer»

SOLUTION :HCL and `H_3O^+` are ACIDS, In which HCl is STRONG ACID
Discussion
22.

What I the SI unit of surface tension.

Answer»

SOLUTION :`NM^(-1) or J m^(-2)`
Discussion
23.

What is meant by L.P.G. ?

Answer»

SOLUTION :LIQUID pentroleum GAS
Discussion
24.

Whichof the following compoundwill exhibit cis trans isomerism

Answer»

2-butene
2-butyne
1-butene
2-butanol

ANSWER :a
Discussion
25.

Write down use of ZSM-5.

Answer»

Solution :A type of ZEOLITE used to convert ALCOHOLS DIRECTLY into GASOLINE.
Discussion
26.

Which solution having more surface tension form the following ? (i) H_(2)O (ii) NaCl

Answer»

Solution :SURFACE TENSION of solution of NACL is more than `H_(2)O`.
Discussion
27.

Which acids are present in the acid rain?

Answer»

SOLUTION :`H_2SO_4 , HNO_3` and HCL
Discussion
28.

Washing soda on standing in air effloresces. How many water molecules are lost

Answer»


Solution :`Na_(2)CO_(3).10 H_(2)O rarr Na_(2)CO_(3).H_(2)O`
Discussion
29.

Volume occupied by one molecule of water (density = 1g cm^(-3)) is

Answer»

`3.0 XX 10^(-23) cm^3`
`5.5 xx 10^(-23) cm^3`
`9.0 xx 10^(-23) cm^3`
`6.023 xx 10^(-23)cm^3`

ANSWER :A
Discussion
30.

Which of these compounds possess highest dipole moment ?

Answer»

SOLUTION :The COMPOUND with more NUMBER of electrons on the valence shell , `:. ` is CONSIDERED to be the most electrongative element .
` :. HZ` is the most electrongative element which has highest dipole moment .
Discussion
31.

Which of the following statements is not correct form the view point of molecular orbital theory ?

Answer»

`Be_(2)` is not a stable molecule
`He_(2)`is not stable but `He_(2) ^(+)`is EXPECTED to exist
Bond strength of `N_(2)`is maximum amongst to homonuclear DIATOMIC molecular belonging to the SECOND PERIOD
The order of energies of molecular orbitals in`N_(2)` molecule is ` sigma 2sltsigma^(**) 2s lt sigma 2p_(z) lt (pi 2p_(x) = pi 2p_(y))` `lt (pi^(**) 2p_(x) = pi^(**) 2p_(y)) lt sigma^(**) 2p_(z)`

Solution :The correct order of energies of molecular orbitals in `N_(2)`molecule is
`sigma _(2s) lt sigma_(2s)^(**) lt (pi_(2_(p_(x))) = pi_(2_(p_(y)))) lt sigma _(2_(p_(z)))lt (pi_(2_(p_(x)))^(**) = pi_(2_(p_(y)))^(**)) lt sigma_(2_(p_(z)))^(**)`
Discussion
32.

Write one chemical reaction for the preparation of D_2O_2

Answer»

SOLUTION :By the ACTION of `D_2SO_4` DISSOLVED in WATER over `BaO_2`.
`BaO_2 + D_2SO_4 to BaSO_4 + D_2O_2`
Discussion
33.

Which statement about the triple point of a substance is/are incorrect?

Answer»

The triple point for a SUBSTANCE varies with pressure
The THREE phases (solid, LIQUID, gas) have same density
The three phases (solid, liquid,gas) are in equilibrium
The three phases(solid, liquid, gas) are indistinguishable in appearance.

ANSWER :A::B::D
Discussion
34.

Which of the following statements related to the modern periodic table is incorrect?

Answer»

The p-block has 6 columns, because a maximum of 6 electrons can OCCUPY all the orbitals in a p-shell.
The d-block has 8 columns, because a maximum of 8 electrons can occupy all the orbitals in a d-subshell.
Each block contains a NUMBER of columns EQUAL to the number of electrons that can occupy that subshell.
The block indicates value of azimuthal quantum number (l) for the last subshell that received electrons in building up the electronic configuration.

Answer :B
Discussion
35.

Upon irradiating californium with neutrons, a scientist discovered a new nuclidehaving massscientist discovered a new nuclide having mass number of 250 and a half-life of 0.50hr. Three hours after the irradiation the observated radioactivity due to the nuclide was10 dis//min. How many atoms of the nuclide were pereparedinitially?

Answer»


ANSWER :`2.766xx10^(4)` ATOMS
Discussion
36.

Which of the following reactions will not product H_(2) gas (a) Fe+HCl" dil" (b) Zn-HCl" dil" (c) Cu+HCl" dil" (d) Ag+HCl" dil"

Answer»

a, C, d
c, d
a, d
B, d

Answer :B
Discussion
37.

What is the main difference between electromagnetic wave theory and planck's quantum theory ?

Answer»

Solution :According to ELECTROMAGNETIC wave THEORY, the energy is emitted or ABSORBED continuously WHEREAS according to Planck's quantum theory, energy is emitted or absorbed discontinousuly, i.e., in certain definite plackets CALLED 'quanta'
Discussion
38.

X mL of H_(2) gas effuses through a hole in a container in 5 seconds. The time taken for the effusion of the same volume of the gas specified below under identical condition is:

Answer»

10 SECONDS : He
20 seconds : 02
25 seconds : CO
55 seconds : 02.

Solution :USE the RELATION `t_2/t_1 = SQRT(M_2/M_1)`
Discussion
39.

Which of the following easily catalyse the decomposition of H_(2)O_(2) when stored ? (i) Rough surface (ii) Sunlight (iii) Dust particles (iv) Metals

Answer»

(i) and (II)
(i),(ii) and (III)
(ii) and (iv)
All of these.

Solution :DECOMPOSITION of `H_(2)O_(2)` is catalysed by metals, rough SURFACES, sunlight, dust particles, glass and alkalies.
Discussion
40.

Two electrons occupying the same orbital are distinguished by……………..

Answer»

AZIMUTHAL QUANTUM number
spin quantum number
magnetic quantum number
orbital quantum number

Solution :Spin quatum number
For the FIRST ELECTRON MS`=+1/2`
For the second electron ms`=-(1/2)`
Discussion
41.

Use the information and data given below to answer the questions (a) to (c ), Stronger intermolecular forces result in higher boiling point. Strength of Lonson forces increases with the number of electrons in the molecule. Boiling point of HF, HCl, HBr and HI are 293 K, 189 K, 206 K and 238 K respectively ?Which type of intermolecular forces are present in the molecules HF, HCl, HBr and HI ?(b) Looking at the trend of boiling points of HCl, HBr and HI, explain out of dipole - dipole interaction and London interaction, which one is predominant here.Why is boiling point of hydrogen fluoride highest while that of hydrogen chloride lowest ?

Answer»

Solution :From the information and data given in the question, we concluded that
(a) In HCl, HBr and HI, dipole - dipole and London forces are present as molecules possess permanent dipole. In HF dipole - dipole, London forces and hydrogen BONDING are present.
(b) Electronegativity of chlorine, bromine and iodine decreases as follows
`Cl gt Br gt I`
So, dipole moment should decrease from HCl to HI Thus, dipole - dipole interaction should also decrease from HCl to HI. But boiling POINT becomes higher on moving from HCI to HI. This MEANS London forces are predominant here.
This is because London forces increases as the number of `e^(-)` in a molecule increases and in this matter, number of electron is increasing from HCl to HI.
(c ) Hydrogen fluide has the highest dipole moment attributes due to the highest electronegativity of fluorine and presence of hydrogen bonding in HF. Thus has highest boiling point.
Discussion
42.

What is the general electronic configuration of group 13 elements ?

Answer»

Solution :[ Noble GAS ] `ns^(2) NP^(1)`
Discussion
43.

What do you mean by Sodium potassium pump?

Answer»

Solution :There is a very CONSIDERABLE VARIATION in the concentration of sodium and POTASSIUM ions found on the OPPOSITE sides of cell membranes is known as Sodium potassium PUMP.
Discussion
44.

What is nodal plane ?

Answer»

SOLUTION :The areaaroundthe nucleuswheretheprobabilityto findelectronis zerois callednodalplane .
Discussion
45.

What is the product when P_4O_10is dissolves in water ?

Answer»

PHOSPHOROUS ACID
Ortho PHOSPHORIC acid
Phosphoric acid
None of these

Answer :B
Discussion
46.

Which was the first reasonable attempt towards the creation of periodic table?

Answer»

NEWLAND's Octaves
Lother MAYER classification
A.E.B. DE charcourtois report
Mosley's MODERN classification

Answer :C
Discussion
47.

Which d'orbital is involved in dsp hybridisation?

Answer»

SOLUTION :`d_(x^(3)-y^(2))`. This is because its four lobes lie ALONG the x-axis and y-axis. The two p ORBITALS intermix along these axis.
Discussion
48.

Whatis thefmolecular formula of thealkane, the 5.6litresofwhichwieght11 gat STP?

Answer»

`CH_(4)`
`C_(4) H_(10)`
`C_(3) H_(8)`
`C_(2)H_(6)`

Answer :C
Discussion
49.

Two moles of an ideal gas initially at 27^(@)C and one atmospheric pressure are compressed isothermally and reversibly till the final pressure of the gasis 10 atm. Calculate q, w AND Delta U for the process.

Answer»

Solution :Here, `N = 2` MOLES , `T = 27^(@) C=300 K, P _(1)= 1 atm,P _(2) =10 atm`
`w= 2.303n RT log. (P_(2))/(P_(1)) = 2.303 xx 2 molxx 8.314 JK^(-1) mol^(-1) xx 300 K xx log. (10)/(1) = 11488 J `
For isothermal compressionof ideal gas, `Delta U = 0`
Further, `Delta U = q+w :. q = -w = -11488J`
Discussion
50.

Which of the following units represent largest amount of energy?

Answer»

CALORIES
Joule
erg
eV

Answer :A
Discussion