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.

Which of the following is a false statement?

Answer»

Free radicals, carbonium ions or carbanions are REACTION intermediates.
Reaction between methane and chlorine in presence of sunlight proceeds via free radical
The ELECTRONEGATIVE atom in the CARBON chain produces +I effect
Homolytic FISSION of C-C bonds gives free radicals

Solution :Thee electronegative atom in the carbon chain produces -I effect.
Discussion
2.

The stronest acid among the following is

Answer»

BUTYRIC acid
formic acid
acetic acid
propionic acid

Answer :B
Discussion
3.

When an iden gas undergoes unrestrained expansion, no cooling occurs because the molecules

Answer»

are above inversion temperature
exert no attractive forces on each other
do WORK EQUAL to the loss in kinetic energy
collide WITHOUT loss of energy

Answer :B
Discussion
4.

Write the value of lowest possible temperature.

Answer»

SOLUTION :`-273^(@)C`
Discussion
5.

Which relationship does hold good for van der Waals' gas under all conditions where all terms have their usual meaning?

Answer»

`PV=NRT`
`(P+(a)/(N^(2)V^(2)))(V-nb)=nRT`
`(P+(a)/(V_(m)^(2)))(V_(m)-B)=RT`
`(P+(a^(2)n)/(V^(2)))(V-nb)=nRT`

ANSWER :c
Discussion
6.

The solubility of CaF_(2) is 2xx10^(-4) mole /litre . Its solubility product is

Answer»

`2.0 xx 10^(-4)`
` 4.0 xx 10 ^(-8) `
` 4 xx 8.0 xx 10 ^(-12) `
` 3.2 xx 10^(-4)`

Solution :`S= 2 xx 10 ^(-4) , M`
` K_(Sp) = 4S^(3) =4 xx (2xx 10 ^(-4))^(3) =32 xx 10 ^(-12) `
Discussion
7.

What is acid rain ? Explain the formation of acid rain by atmospheric pollutant.

Answer»

Solution :Rain water has a pH of 5.6. Because rain water reacts with `CO_2` present in atmosphere and formed `H^+` ions.
`H_2 O_((l)) + CO_(2(g)) hArr H_2 CO_(3(aq))`
`H_2 CO_(3(aq)) hArr H_(("aq"))^+ + HCO_(3(aq))^(-)`
When the pH of the rain water drops below 5.6, it is called acid rain.
Acid rain refers to the ways in which acid from the atmosphere is deposited on the earth.s surface. Oxides of nitrogen and sulphur which are acidic in nature can be blown by wind ALONG with solid PARTICLES in the atmosphere and finally settle down either on the ground as dry DEPOSITION or in water, fog and snow as wet deposition.

Oxides of sulphur and nitrogen formed and mix in the atmosphere. Which is responsible for the acid rain. Burning of fossil fuels which contain sulphur and nitrogenous matter such as coal and oil in power stations and furnaces or petrol and diesel in motor engines produce sulphur dioxide and nitrogen oxides.
`SO_2 and NO_2` after OXIDATION and reaction with water are major contributors to acid rain, because polluted air usually contains particulate matter that catalyse the oxidation.
`2SO_(2(g)) + O_(2(g)) + 2H_2 O_((l)) to 2H_2 SO_(4(aq))`
`4NO_(2(g)) + O_(2(g)) + 2H_2 O((l)) to 4HNO_(3(aq))`
Thus, ammonium salts are also formed and can be seen as an atmospheric haze aerosol of fine particles.
Aerosol particles of oxides or ammonium salts in rain drops result in wet deposition. `SO_2` is also absorbed directly on both solid and liquid ground surfaces and is thus deposited as drydeposition
Discussion
8.

Which of the fallowing has highest chlorine content?

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PYRENE
DDT
CHLORAL
GAMMAXENE

SOLUTION :Pyrene
Discussion
9.

Write phosphorous reacts with aqueous caustic soda to give hypophosphite and phosphine.

Answer»

Solution :a) The ionic skeleton equation is
`P_(4)overset(OH^(-))rarrPH_(3)+H_(2)PO_(2)^(-)`
b) Writing oxidation numbers
`overset(0)(P_(4))rarroverset(-3)(P)overset(+1)(H_(3))+overset(+1)(H_(2))overset(+1)(H_(2))overset(+1)(P)overset(-2)(O_(2)^(-))`
c) Locating atoms undergoing change in oxidation numbers
`overset(0)(P_(4))rarroverset(-3)(P)H_(3)+H_(2)overset(+1)(P)O_(2)^(-)`
d) Dividing the reaction into two two halves and balancing in acidic medium, separately
Oxidation half - reaction : `P_(4)rarrH_(2)PO_(2)^(-)`
Step 1 : Balance phosphorous atoms
`P_(4)rarr4H_(2)PO_(2)^(-)`
Step 2 : Balance oxygen atoms
`P_(4)+8H_(2)Orarr4H_(2)PO_(2)^(-)`
Step 3 : Balance hydrogen atoms
`P_(4)+8H_(2)O+8OH^(-)rarr4H_(2)PO_(2)^(-)+8H_(2)O`
Step 4 : Balance CHARGE
`P_(4)+8OH^(-)rarr4H_(2)PO_(2)^(-)+4e^(-)".....(a)"`
Reduction half - reaction : `P_(4)rarrPH_(3)`
Step 1 : Balance phosphorous atoms
`P_(4)rarr4PH_(3)`
Stpe 2 : Balance hydrogen atoms
`P_(4)+12H_(2)Orarr4PH_(3)+12OH^(-)`
Step 3 : Balance charge
`P_(4)+12H_(2)O+12E^(-)rarr4PH_(3)+12OH^(-)`
e) Equalising the electrons and adding the two halves
`"eq (a)"xx3+"eq (b)"xx"1, we get"`
`{:(3P_(4)+24H_(2)Orarr12H_(2)PO_(2)^(-)+12e^(-)),(P_(4)+12H_(2)O+12e^(-)rarr4PH_(3)+12OH^(-)),(bar(4P_(4)+12OH^(-)+12H_(2)Orarr"")),(""4PH_(3)+12H_(2)PO_(2)^(-)),(I_(4)+3OH^(-)+3H_(2)OrarrPH_(3)+3H_(2)PO_(2)^(-)):}`
This is the balanced equation.
Discussion
10.

When CH_(2) = CH - COOH is reduced with LiAlH_(4), the compound obtained will be

Answer»

`CH_(3) - CH_(2) - COOH`
`CH_(2) = CH - CH_(2)OH`
`CH_(3)CH_(2) - CH_(2)OH`
`CH_(3) - CH_(2) - CHO`

Solution :When `CH_(2) = CH - COOH` is reduced with `LiAlH_(4) : CH_(2) = CH - CH_(2)OH` COMPOUND is formed because `LiAlH_(4)` reduces `-COOH` to `CH_(2)OH` WITHOUT affecting `C = C` BOND
Discussion
11.

what are the biological importance of sodium and potassium.

Answer»

SOLUTION :The biological importance of SODIUM and potassiumk are : (a) Both Na and K are present in body 0.15% and 0.35% (b) Na is found OUTSIDE the cells in the blood PLASMA as well as in the intercellular fluids. K ions are present inside cells.
Discussion
12.

What is polar covalent bond? Explain with example.

Answer»

Solution :(i) Ifa covalent bnd is formed between atoms having different electronegativities, the atom with higher electronegativity will have greater tendency to attract the shared pair of ELECTRONS towards itself than the other atom. As a result, the cloud of shared electron pair gets distorted and polar covalent bond is formed.
(ii) Example: HF- Hydrogen fluoride: The electronegativities of hydrogen and fluorine on Pauling.s SCALE are 2.l and 4 respectively. It MEANS that fluorine attract the shared pair of electrons approximately twice as much as hydrogen which leads to partial NEGATIVE charge OuoThe atom and partial positive charge on hydrogen atom. Hence , the H-F bond is said to be a polar covalent bond.
Discussion
13.

Which of the following parameters correctly represent conditions for a spontaneous process with no non P-V work involved? (P) (dH)_(S,P)lt0 (Q) (dU)_(S,P)lt0 (R ) (dG)_(T,P)lt0 (S) (dH)_(P,T)gt0 (T) (d,S)_(universe)gt0 (U) (dS)_(U,V)gt0

Answer»

Options (Q),(R ) and (T) are CORRECT
Options (P),(T) and (U) are correct
Options (P),(R ) and (T) are incorrect
Options (Q) and (R ) are incorrect

Answer :B
Discussion
14.

Which of the following unit is derived unit ?

Answer»

TEMPERATURE
Time
MASS
DENSITY

Solution :Density `=("Mass")/("Volume") = (KG)/(m^(3))`
Discussion
15.

Write IUPAC name of following

Answer»

SOLUTION :
Discussion
16.

The standardmolar entropy of H_(2)O(l)is 70 JK^(-1) mol^(-1). Will the standard molar entropy of H_(2)O(s) be more, or less than 70 JK^(-1) mol^(-1) ?

Answer»

Solution :In ice, moleculesof`H_(2)O` are LESS RANDOM than in LIQUID water. HENCE , molar entropy of ice, `H_(2)O(s)`, will be less thanthat of liquid water, `H_(2)O(l)`.
Discussion
17.

Which of thefollowingspecieshas thehighestelectronaffinity ?

Answer»

`F^(-)`
`O `
`O^(-)`
`Na^(+)`

Solution :Electronaffinityis THEAMOUNT ofenergyreleased . Now energyis releasedwhen Oacceptsan electron.Butenergyhas to be spentwhenan electron adds to`F^(-) ,O^(-)` and `Na^(+)`. Thusoption (B) is CORRECT.
Discussion
18.

What are crystalline hydrates? Explain it with example.

Answer»

Solution : (i) In these, hydrogen bonding is very important. OFTEN the water molecules serve to fill in the interstices and bind together structure.
(ii) A specific example is `CuSO_(4)5H_(2)O`.
(iii) ALTHOUGH there are five water molecules for every divalent copper ion, only four are coordinated to the cation, it.s six-coordination being completed from sulphate ANIONS. The fifth water molecule is held in place of hydrogen bonds, O- H O, between it and TWO coordinated water molecules and then coordinate sulphate anion.
(iv) Water forms hydrated salts during crystallization. Examples, `Na_(2)CO_(3)10H_(2)O`, `FeSO_(4).7H_(2)O`.
(v) The water present in the hydrates is called as water of hydration
Discussion
19.

Which one of the compound is achiral :

Answer»


`CH_3 - CH_2 - CHOHCN`

SOLUTION :
Discussion
20.

What will be the change in boiling point of alkene compound on addition of each -CH_(2) group ?

Answer»

Solution :On addition of each `-CH_(2)` BOILING point increases approximately by 20-30 K.
Discussion
21.

The solubility of metal halides depends on their nature , lattice enthalpy and hydration enthalpy of the individual ions . Amongst fluorides of alkali metals , the lowest solubility of LiF in water is due

Answer»

ionic nature of lithium FLUROIDE
HIGH lattice enthalpy
high hydration enthalpy for lithium ion
low IONISATION enthalpy of lithium atom

Solution :Due to small size of `Li^(+)` and `F^(-)` IONS , lattice enthalpy is much higher than hydration enthalpy and hence LiF is least soluble among alkali metal fluorides .
Discussion
22.

Which of the following statements is(are) correct

Answer»

In SEMI conductor , electrical resistivity DECREASES with a rise in temperature
In METALLIC conductor , electrical resistivity increases with a rise in temperature
In super conductor , electrical resistivity decreases gradually with the LOWERING temperature
A unit cell of an ionic crystal shares some of its ions with other unit cells.

Answer :A::B::C::D
Discussion
23.

The surface tension of water at 20°C is 72.75 dyne cm^(-1) . Its value in SI system is

Answer»

`2.275 N m^(-1)`
`0.7275 N m^(-1)`
`0.07275 N m^(-1)`
NONE of the above 

ANSWER :C
Discussion
24.

The state of a gas can be described by quotingthe relationship between "…................".

Answer»

pressure, VOLUME, TEMPERATURE
temperature,amount,pressure
amount, volume, temperature
pressure, volume, temperature, amount

Solution :`PV= nRT`. THUS , P,V,T and n describe the state of the SYSTEM.
Discussion
25.

whichof thefollowingCORRECTLYreprsents bond -lineformulaof - n- butane?

Answer»




ANSWER :C
Discussion
26.

Which of the following properties increases across a period ?

Answer»

REDUCING PROPERTY 
Size of ATOM 
Acidic nature of oxides
Metallic property 

ANSWER :C
Discussion
27.

What happens when calcium carbide is treated with water?

Answer»

Ethane is formed
Methane and ethane are formed
ETHYNE is formed
Ethene and ethyne are formed.

Solution :When `CaC_(2)` reacts with water, it GIVES ethyne. `CaC_(2)+2H_(2)O to CH-=CH+Ca(OH)_(2)`
Discussion
28.

Which of the following solution has the highest boiling point ?

Answer»

1) `5.85%` solution of NaCl
2) `6.0%` solution of urea
3) 18% solution of glucose
4) All have same BOILING point

ANSWER :A
Discussion
29.

What change would be observed when covalent bond is form ?

Answer»

SOLUTION :OCTET STRUCTURE is FORM.
Discussion
30.

What are ternary Hydrides ? Give examples.

Answer»

Solution :Ternary hydrides are COMPOUNDS in which the MOLECULAR is constituted by HYDROGEN and TWO types of element , e.g., `LiB_(4)` or `LiAlH_(4)`.
Discussion
31.

Which of the following relation is correct for an ideal regarding its pressure (p) and translational kinetic energy per unit volume (E ) ?

Answer»

`p=(3)/(2)E`
`p=(2)/(3)E`
`p=(1)/(2)E`
`p=2E`

Solution :`(B)E=(E')/(V)=(1)/(2)(mNU_(ms)^(2))/(V)=(3)/(2)xx(1)/(3)(mNU_(ms)^(2))/(V)=(3)/(2)p`
`P=(2)/(3)E`
Discussion
32.

What do you meanby Entropyof vaporisation or Entropy offusion or Entropy of sublimation .

Answer»

SOLUTION :REFER to the TEXT.
Discussion
33.

What volume of H_(2) at NTP is required to convert 2.8g of N_(2) in to NH_(3)?

Answer»

2240ml
22400ml
6.72lit
224lit

Answer :C
Discussion
34.

What are non-ideal solution ? Give example.

Answer»

Solution :(i) The solution which do not obey Raoult.s law over the ENTIRE range of concentration are CALLED non-ideal solutions. The devintion of the non-ideal solution from the Raoult.s law may be POSITIVE (or) negative.
(II) Example. Ethyl alcohol and cyclohexane.
Discussion
35.

Which of the following is associated with Torsional strain ?

Answer»

Repulsion between BOND pair of electrons
Inductive effect
Bond angle STRAIN
Attraction of OPPOSITE charges

Solution :Repulsion between bond pair electrons is DEFINED as TORSIONAL strain.
Discussion
36.

The uncertainity in the momentum of a particle is 3.31 xx 10^(-2) kg ms^(-1). The uncertainity in its position is (in metres)

Answer»

`1.59xx10^(-33)`
`0.33xx10^(-30)`
`0.4xx10^(-20)`
`3.3xx10^(-24)`

Solution :`Delta_x= H/(4pi m DELTA V)`
Discussion
37.

When 2-methyl butyl bromide is treated with sodium ethoxide I ethanol, what will be the major product?

Answer»

2-methyl but-2-ene
3-methyl but-1-ene
2-methyl but-1-ene
2-methyl-sodium-butoxide

Answer :A
Discussion
38.

What is mechanism of the reaction?

Answer»

Solution :In the ORGANIC reactions, that series of SIMPLE STEPS which COLLECTIVELY represent the chemical change, from substrate to product, this is CALLED as the mechanism of the reaction. The sloweststep in the mechanism determines the overall rate of the reaction.
Discussion
39.

When PbO_(2) reacts with concentrated HNO_(3), the gas evolved is

Answer»

`NO_(2)`
`O_(2)`
`N_(2)`
`N_(2)O`

ANSWER :B
Discussion
40.

The value of amgnetic moment is zero in the case of antiferromagnetic substances because the domians …….

Answer»

get oriented in the direction of the APPLIED MAGNETIC field.
get oriented OPPOSITE to the direction of the applied magnetic field.
are oppositely oriented with resoect to each other WITHOUT the applications of amgnetic fields.
cancel out each other's magnetic MOMENT.

Answer :C::D
Discussion
41.

Which point defect in crystals of a solid decreases the density of the solid ?

Answer»

SOLUTION :SCHOTTKY DEFECT.
Discussion
42.

What is photoelectric effect ? State the result of photoelectric effect experiment that could not be explained on the basis of laws of classical physics. Explain this effect on the basis of quantum theory of electromagnetic radiations.

Answer»

Solution :Photoelectric effect : When radiation with certain minimum frequency (p0) strike the surface of a metal, the electrons are ejected from the metal surface. This phenomenon is called photoelectric effect. The electrons emitted are called photoelectron

Equipment for studying the photoelectric effect. Light of a particular frequency strikes a clean metal surface inside a vacuum chamber. Electrons are ejected from the metal and are counted by a detector that measures their kinetic energy. The result observed in this experiment were (i) The electrons are ejected from the metal surface as soon as the beam of light strikes the surface, i.e., there is no time lag between the striking of light beam and the ejection of electrons from the metal surface. (ii) The num ber of electrons ejected is proportional to the intensity or brightness of light. (iii) For each metal, there is a characteristic minimum frequency, VQ (also known as threshold frequency) below w hich photoelectric effect is not observed. At a frequency , the ejected electrons come out with certain kinetic energy. The kinetic energies of these electrons increases with the increase of frequency of the light used. The above observation cannot be explained by the electromagnetic wave theory. According to this theory, since radiations were continuous, therefore, it should be possible to accumulate energy on the surface of the metal, irrespective of its frequency and thus, radiations of all frequencies should be able to eject electrons. Similarly, according to this theory, the energy of the electrons ejected should depend upon the intensity of the INCIDENT radiation. Particle Nature of Electromagnetic Radiation : To explain the phenom ena of ‘black body radiation’ and ‘photoelectric effect’, Max Planck in 1900, put forward a theory known after his NAME as Planck.s quantum theory. This theory was further extended by Einstein in 1905. The important points of this theory are as FOLLOWS : (i) The radiant energy is emitted or absorbed not continuously but discontinuously in the form of small discrete packets of energy.Each such packet of energy is called a ‘quantum’. In case of light, the quantum of energy is called a ‘photon’. (ii) The energy of each quantum is directly proportional to the frequency of the radiation, i.e., E v or E = hv where, h is a proportionality constant, called Planck.s constant, Its value is approximately equal to `6.626 xx 127 erg s or 6.626 xx 10^(34)` JS. (iii) The total amount of energy emitted or absorbed by a body will be some whole number quanta.
Hence, E = nhv (where, n is any INTEGER),
Discussion
43.

Which bond angelthetawould result in the maximum dipole moment for the triatomic molecule XY_2 shown below ?

Answer»

` THETA = 90^@`
` theta = 120^@`
` theta =150^@`
` theta =180^@`

SOLUTION :` mu =sqrt(mu_1^2 +mu_2^2 + 2mu_1mu_2 cos theta , ) if `theta = 90^@`.
`mu` is MAXIMUM .
Discussion
44.

What is the significance of the term isolated gaseous atom while defining the ionization enthalpy.

Answer»


Answer :USEFUL for COMPARING ionization enthalpies of atoms of DIFFERENT elements
Discussion
45.

Writethe namesand atomic numbers of the followingelements : (i) The fourthalkali metal (ii) The thirdalkaline earthmetal (iii) Thefifthelementof the firsttransition series (iv) Thefirstinnertransition element and (v) Thesixthnoblegas.

Answer»

Solution :(i) Rb (Z= 37), (ii) CA (Z = 20 ), (ii) Mn(Z=25), (IV) CE(Z= 58), (v) Rn (Z=86)
Discussion
46.

Which of the following reactions will produce the 2-pentyne in good yield? CH_(3)-CH_(2)-C-=C-CH_(3)

Answer»


`CH_(3)-C-=CN AOVERSET(CH_(3)CH_(2)Br)to`
`CH_(3)-CH_(2)-overset(O)overset(||)(C)-Hunderset(Et_(2)O)overset(CH_(3)CH_(2)MgBr)tooverset(H_(3)O^(+))to`
`CH_(3)-CH_(2)-CH_(2)-underset(Br)underset(|)(C)H-CH_(2)-Brunderset("heat")overset(NAOH)to`

Answer :B
Discussion
47.

Which of the following equation is a balanced equation ?

Answer»

`FeS_(2) + 4O_(2) rarr 8 SO_(2) + 2Fe_(2) O_(3)`
`4FeS_(2) + 6O_(2) rarr2Fe_(2) O_(3) + 8 SO_(2)`
`4FeS_(2) + 11O_(2) rarr 2 Fe_(2) O_(3) + 8SO_(2)`
` 2FeS_(2) + 11O_(2) rarr Fe_(2) O_(3) + 6SO_(2)`

Answer :C
Discussion
48.

Write the chemical reactions to show the amphoteric nature of water.

Answer»

Solution :WATER is AMPHOTERIC in NATURE and it behaves both as an acid as well as base. With acids STRONGER than itself (eg. `H_(2)S`) it behaves as a base and with bases stronger than itself (eg, `NH_(3)`) it acts as an acid.
(i) As a base: `H_(2)O_((L))+H_(2)S_((aq))toH_(3)O_((aq))+HS^(-)`
(ii) As an acid: `H_(2)O_((l))+NH_(3(aq))toOH_((aq))^(-)+NH_(4(aq))^(+)`
Discussion
49.

Which of the following molecule does not obey the octet rule and also has Ione pair on the central atom?

Answer»

`"CC"l_(4)`
`PCl_(3)`
`NH_(3)`
`SCl_(4)`

ANSWER :D
Discussion
50.

Which elements of group shows difficult tendency of value electron gain enthalpy?

Answer»

Solution :OXYGEN and sulphur shows different tendency of electron gain ENTHALPY because electron gain enthalpy of oxygen is LESS NEGATIVE than sulphur.
Electron gain enthalpy of fluorine is less negative than chlorine.
Discussion