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 one of the following conditions will favour maximum formation of the product in the reaction,A_2(g) + B_2(g) iffX_2(g), Delta_r H = -X kJ

Answer»

High TEMPERATURE and low pressure
Low temperature and high pressure
High temperature and high pressure
Low temperature and low pressure

Solution :MOLES of gas are DECREASE (from 2 to 1) for forward reaction at low temperature because the reaction is EXOTHERMIC, So higher pressure will PRODUCED more product.
2.

Which of the following easily reacts with water producing hydrogen?

Answer»

`PH_(3)`
`B_(2)H_(6)`
`CH_(4)`
`H_(2)S`

Solution :`B_(2)H_(6)+6H_(2)Orarr2B(OH)_(3)+6H_(2)uparrow`
3.

Which of the following sets of atomic numbers is of the alkali metals ?

Answer»

`2,10,18`
`7,17,27`
`15,320,30`
`3,11,19`

SOLUTION :The atomic NUMBER of ALKALI metals are `3,11,19,37,55 and 87.`
4.

What are the value of n, l and m for 2p_(x) and 3p_(z) orbitals ?

Answer»

SOLUTION :For `2p_(X), n = 2, l = 1, m = +1`
For `3p_(z), n = 3, l = 1, m = 0`
5.

Which one of the following reactions does not involve either oxidation or reduction

Answer»

`VO_(2)^(+) to V_(2)O_(3)`
`Na to Na^(+)`
`CrO_(4)^(2-) to Cr_(2)O_(7)^(2-)`
`Zn^(2+) to Zn`

Answer :C
6.

What happens when aniline is treated with methyl chloride in presence of AlCl_3 ?

Answer»

It under GOES friedel craft reaction to form a mixture of P - methyl and O-methyl aniline.
It DOSE not undergo friedel craft reaction because AlCl, reacts with aniline instead of reactingwith alkyl HALIDE.
Aniline gets POSITIVE charge and deactivated for electrophilic substitution.
Both b and c

Solution :The lone pair of electrons on N MAKES aniline to react with `AlCl_3` hence is not available to for forming `CH_3^(oplus)`
7.

Why at low pressures, the real gas behaves as ideal gas?

Answer»

Solution :At LOW PRESSURES, when volume is large, both correction factors in the van der Waals. equations may be neglected.
The equation `(P+(a)/(V^2)) (V - b) = RT,` reduces to PV =RT, ideal gas law.
This is nothing but representing the LIMITING behaviour of gases at infinite small pressures.
8.

Which of the following options represents the correct bond order :

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`O_(2)^(-) GT O_(2) gt O_(2)^(+)`
`O_(2)^(-) LT O_(2) lt O_(2)^(+)`
`O_(2)^(-) gt O_(2) lt O_(2)^(+)`
`O_(2)^(-) lt O_(2) gt O _(2)^(+)`

SOLUTION :`O_(2) = 2, O_(2)^(-) = 1.5 , O_(2)^(+) = 2.5 thereforeO_(2)^(-) lt O_(2) lt O_(2)^(+)`
9.

Using the data given below, calculate the value of equilibrium constant for the reaction. underset("Acetylene")(3HC-=CH(g)) hArr underset("Benzene")(C_(6)H_(6)(g)) at 298 K , assuming ideal gas behaviour. Delta_(f)G^(@)for HC-= CH(g) = 2.09 xx 10^(5) J mol^(-1),Delta_(f)G^(@)forC_(6)H_(6)(g) =1.24xx 10^(5) J mol^(-1) R = 8.314 J K^(-1) mol^(-1) Based on your calculated value, comment whether this process can be recommended as a practical method for making benzene.

Answer»


Solution :`Delta_(r) G^(@) =Delta_(f)G^(@) (C_(6)H_(6)) - 3 Delta_(f)G^(@)(HC -= CH) = 1.24 xx 10^(5) - 3 ( 2.9 xx 10^(5)) J = - 5.03 xx 10^(5)J`
`Delta_(r)G^(@) = - 2.303 RT LOG K `. Calculate K
`DELTA _(r)G^(@) ` is negative and K is very high . Hence, the PROCESS can OCCUR easily.
10.

Use of Al for domestic purpose is reduced now. Why ?

Answer»

SOLUTION :Aluminium metal and COMPOUNDS of aluminium are TOXIC. Hence the utility is now REDUCED.
11.

Which of the following presents the correct order of the acidity in the given compounds ?

Answer»

`FCH_(2)COOH gt ClCH_(2)COOH gt BrCH_(2)COOH gt CH_(3)COOH`
`CH_(3)COOH gt BrCH_(2)COOH gt ClCH_(2)COOH gt FCH_(2)COOH`
`FCH_(2)COOH gt FCH_(2)COOH gt BrCH_(2)COOH gt Cl_(2)CH_(2)COOH`
`BrCH_(2)COOH gt ClCH_(2)COOH gt FCH_(2)COOH gt CH_(3)COOH`

Answer :A
12.

When Q_(sp) is used ?

Answer»

Solution :When in representation of `K_(sp)` ONE or more species concentration is not equal to concentration of `K_(sp)` than `Q_(sp)`USED.
13.

Which one of the following is non -aromatic ?

Answer»




ANSWER :D
14.

What is polarisation?

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SOLUTION :The ABILITY ofa cation to POLARISE an anion is CALLED its polarising ability and the tendency of the anion to get polarised is called its polarisability. This plenomenon is known as POLARISATION.
15.

What is oxidation number of Cl in bleacing powder ?

Answer»

Solution :Molecular formula : `CaOCl_(2),Ca^(+2)(OCl^(-))Cl^(-)`
`THEREFORE` Oxidation NUMBER of Cl in `OCl^(-)=+1`
and oxidation number of SECOND Cl = -1
`therefore` Average oxidation number is ZERO.
16.

Which of the following is wrong ?

Answer»

(1) Degree of DISSOCIATIONS of a weakelectrolyte increase with dilution.
Increases in temperature increases the ionisation.
Strong ELECTROLYTES are ionised completelyeven at MODERATE concnetrations.
Additions of `NH_4 Cl "to"NH_4OH`increases the ionisation of the LATTER.

Solution :Common ion effect decreasesdissociation
17.

Which of the following is an intermediate in the reaction of benzene with CH_3Cl and AlCl_3 ?

Answer»




Solution :Aluminum chloride is a strong LEWIS acid and reacts with methyl chloride to form a methyl carbocation , which is the ELECTROPHILE in the next STEP of the REACTION.
18.

When R-C-=CH is treated with cuprous in ammonical medium, product formed is

Answer»

`R-C-=C-CU`
`Cu-C-=CH`
`CuC-=C Cu`
`R-C-=C-R`

ANSWER :A
19.

Which of the following sequences contain atomic numbers of only representative elements ?

Answer»

3,33,53,87
2,10,22,36
7,17,25,37,48
9,35,51,88

Solution :ELEMENTS of s and p-block elements are CALLED REPRESENTATIVE elements. Elements of d-block (Z = 21-30, 39-48, 57 and 72-80, 89 and 104-112) are called transition elements while those of fblock (with Z 58-71 and Z = 90-103) are called INNER transition elements.
With reference to this division, elements listed under option (A) and option (D) are all representative elements.
20.

What is the energy of state in a triply ionized beryllium (Be^(++)) whose radius is equal to that of ground state of hydrogen ?

Answer»


SOLUTION :Radius of GROUND STATE of HYDROGEN atom
`= 0.529 Å implies0.529 = 0.529 xx (n^2)/(4) impliesn=2 `
21.

Which of the followinghydrogen halide is most volatile ?

Answer»

HF
HCl
HBr
HI.

Solution :Most valatile HYDROGEN hailde is the ONE which
has least BOILING POINT , viz , HCl .
22.

What is the thermodynamic product obtained from the addition of 1 mole of HBr to 1,3-butadiene?

Answer»

1-bromo-2-butene
3-bromo-1-butene
4-bromo-1-butene
3-bromo-2-butene

SOLUTION :3-Bromo-1-butene is the kinetic product formed upon reaction of HBr with 1,3-butadiene It is formed by ADDITION of bromide anion to the resonance STABILIZED allylic carbocation formed by protonation of the diene. HOWEVER, there is a more STABLE isomeric product which is the thermodynamic product.
23.

The wave function for an orbital is H-atom is given as psi=(sqrt(2)/(81sqrt(pi)))((1)/(a_(0)))^((3)/(2))(6-(r )/(a_(0)))((r )/(a_(0)))e^((r )/(3a_(0))). sinthetasinphi The orbital is :

Answer»

`2s`
`3P`
`2P`
`3D`

Answer :A::B
24.

Write the molecular formula of iron (III) hexacyanoferrate (II).

Answer»

Solution :`Fe_(4)[Fe(CN)_(6)]_(3)`.
25.

What would have happened if the greenhouse gases were totally missing in the earth's atmosphere ? Discuss

Answer»

Solution :The solar energy RADIATED back from the earth surface is absorbed by the greenhouse gases (i.e. , `CO_2, CH_4 , O_3 , CFC's`and water vapour ) present near the earth's surface Thus, they heat up the atmosphere near the earth's surface and KEEP it WARM As a result, they keep the temperature of the earth constant and HELP in the growth of PLANTS and existence of life on the earth. If there were no greenhouse gases, there would have no vegetation and life on the earth
26.

The total energy of electron in an atom is a combination of potential energy and kinetic energy. If total energy is -E for an electron in an atom, then its K.E. and P.E. respectively are

Answer»


ANSWER :`-2E`
27.

Which of the following compound(s) has /have percentage of carbon same as that in ethylene (C_2H_4) .

Answer»

BENZENE
ethane
propene
ethyen

28.

What is Gay - Lussac.s formula ?

Answer»

`p PROP T`
`pT^(-1)=K`
`p_(1)T_(2)=p_(2)T_(1)`
All of these

ANSWER :D
29.

Which alkali metal carbonate decomposes on heating to liberate CO_2?

Answer»

SOLUTION :`Li_2CO_3`
30.

Volume of 0.1 M K_(2)Cr_(2)O_(7) required to oxidise 35 mL of 0.5 M FeSO_(4) solution is :

Answer»

29.2 mL
17.5 mL
175 mL
145 mL

Solution :N//A
31.

Which metals are present in Crinite Ore ?

Answer»

K, BA
Be, AL
K, Mg
Mg, CA

Answer :C
32.

Which of the following act as a stabiliser for the storage of H_(2)O_(2)?

Answer»

ALKALI
DUST
UREA
None of these.

Solution :`H_(2)O_(2)` decomposes slowly on exposure to light.
`2H_(2)O_(2(l))to 2H_(2)O_((l))+O_(2(g))`
In the presence of metal surfaces or traces of alkali (present in glass containers), the above REACTION is catalysed. It is, therefore, stored in wax-lined glass or plastic vessels in dark. Urea can be added as a stabiliser. It is kept away from dust because dus can induce explosive decomposition of the compound.
33.

The state of equilibrium is in a dynamic balance between forward and backward reaction. This balance can be disturbed by changing concentration, temperature or pressure. If done so a cartain net change occurs in the system. The direction of change can be predicted with the help of Le Chatelier principle. It states that when a system in equilibrium is disturbed by a change in concentration of temperature, a 'net' change occurs in it in a direction that tends to decrease the disturbing factor. Consider the following exothermic heterogenous equilibrium, M_(2)O(s)+2HNO_(3)(aq)hArr2MNO_(3)(aq)+H_(2)O(l) withK_(C)=3 at 300K. Select the incorrect option.

Answer»

Addition of `H_(2)O(l)` to above EQUILIBRIUM has no EFFECT on equilibrium COMPOSITION `(%)` of `HNO_(3)` and `MNO_(3)`.
On dilution, concentration of both `HNO_(3)` and `MNO_(3)` decreases.
At 310 K, `K_(C)lt3`.
`K_(C)` is dependent on equilibrium concentration of `HNO_(3)`.

Answer :D
34.

The state of equilibrium is in a dynamic balance between forward and backward reaction. This balance can be disturbed by changing concentration, temperature or pressure. If done so a cartain net change occurs in the system. The direction of change can be predicted with the help of Le Chatelier principle. It states that when a system in equilibrium is disturbed by a change in concentration of temperature, a 'net' change occurs in it in a direction that tends to decrease the disturbing factor. For the equilibrium, underset(("yellow"))(Fe^(3+)(aq))+SCN^(-)(aq)hArrunderset(("deep red"))[[Fe(SCN)^(2+)](aq) Select the correct option.

Answer»

Addition of `H_(2)C_(2)O_(4)` which FORMS `[Fe(C_(2)O_(4))_(3)]^(3-)` DEEPENS red colour.
Addtion of `H_(2)O` has no effect on the colour.
Addition of `SCN^(-)` intensifies red colour.
Addition of `Hg^(2+)` which forms `[Hg(SCN)_(4)]^(2-)` deepens red colour.

Answer :C
35.

Which colour is imparted when Lithium, sodium, potassium and Rubidiumk undergoes flame test?

Answer»

Solution :Lithium `to` CRIMSON RED
Sodium `to` yellow or golden yellow
Potassium `to` Pale Violet
Rubidium `to` REDDISH violet
36.

Van der Waal's forces are attraction inter molecular forces. Write the names of any two types of van der Waal's forces.

Answer»

SOLUTION :Dipole-dipole FORCES, DISPERSION forces.
37.

Which of the following is the most stable intermdiate formed during the acid catalysed dehydration of neopentyl alcohol

Answer»

`(CH_(3))_(3)Coverset(o+)(C)H_(2)`
`CH_(3)overset(o+)(C)HCH_(2)CH_(3)`
`(CH_(3))_(2)overset(o+)(C)CH_(2)CH_(3)`
all the THREE are equally stable.

Solution :The NEOPENTYL alcohol gives more stable `3^(@)` carbocation as an intermediate via rearrangement INVOLVING methyl shift.
`(CH_(3))_(3)C CH_(2)OH underset(-H_(2)O)overset(H^(+))rarr (CH_(3))_(3)C CH^(o+) overset("Methyl shift")rarr underset(3^(@)-"carbocation")((CH_(3))_(3)overset(o+)(C)CH_(2)CH_(3))`
38.

Which sequence of reaction produce

Answer»

`CH_3-C -= C CH_3 underset("Lindlar's catalyst")overset(D_2)to`
`CH_3C -= C CH_3 underset((2) CH_3COOD) overset((1) BD_3)to`
`CH_3C -= C CH_3 underset((2) CH_3COOH)overset((1) BD_3,THF)to`
`CH_3C -= CCH_3 underset((2)CH_3COOD)overset((1)BH_3, THF)to`

Solution :Alkynes on deuteration / hydrogentaion in the presecne of Lindlar.s catalyst, `BD_3`, Nickelboride, UNDERGOES SYNADDITION and gives Cis Alkene.
39.

What are the products in the following sequence of reaction Compound (B) is:

Answer»




all of these

Answer :C
40.

When conc. H_(2)SO_(4) was treated with K_(4) [Fe(CN)_(6)], CO has was evolved. By mistake, somebody used dilute H_(2)SO_(4) instead of conc, H_(2)SO_(4), then the gas evolved was

Answer»

`CO`
`HCN`
`N_(2)`
`CO_(2)`

Solution :`K_(4)[Fe(CN)_(6)]+underset("conc.")(6H_(2)SO_(4))+6H_(2)O RARR 2K_(2)SO_(4)+FeSO_(4)+3(NH_(4))_(2)SO_(4)+6CO uarr`
`K_(4)[Fe(CN)_(6)]+underset("(dil.)")(3H_(2)SO_(4)) rarr 2K_(2)SO_(4)+FeSO_(4)+6HCN uarr`
41.

Which is the correct increasing order of boiling points of the following compounds ? 1-Bromoethane, 1-Bromopropane, 1-Bromobutane, Bromobenzene

Answer»

`"BROMOBENZENE" LT "1-Bromobutane" lt "1-Bromopropane" lt "1-Bromoethane"`
`"Bromobenzene" lt "1-Bromoethane" lt "1-Bromopropane" lt "1-Bromobutane"`
`"1-Bromopropane" lt "1-Bromobutane" lt "1-Bromoethane" lt "Bromobenzene"`
`"1-Bromoethane" lt "1-Bromopropane" lt "1-Bromobutane" lt "Bromobenzene"`

ANSWER :D
42.

Which of the following is not an application of adsorption phenomenon?

Answer»

PURIFICATION of muddy water
use of Ni in hydrogenation of oil
separation of mixture of amino ACIDS by chromatography
Cottrell PRECIPITATION

SOLUTION :Cottrell precipitation deposites CARBON from smoke.
43.

Which of the following has highest hydration energy

Answer»

`MgCl_(2)`
`CaCl_(2)`
`BaCl_(2)`
`SrCI_(2)`

Solution :The ORDER of hydration energy of alkaline earth metal is `Be^(2+) lt MG^(2+) lt CA^(2+) lt Sr^(2+) lt Ba^(2+)`
44.

What happens when (i) Sodium metal is dropped in water?(ii) Sodium metal is heated in free supply of air? (iii) Sodium peroxide dissolves in water?

Answer»

Solution :`2NA + 2H_(2)O to 2NaOH + H_(2)`
(ii) `2Na +O_(2) to2Na_(2)OH_(2)`
(iii) `Na_(2)O_(2) + 2H_(2)O to 2NaOH + H_(2)O_(2)`
45.

The temperature at which second virial coefficient of a real gas is zero is called

Answer»

critical temperature
Boyle temperature
INVERSION temperature
eutetic point

Solution :The virial EQUATION for a real gas is
` PV=A+(B)/(V)+…`
At Boyle temperature, the gas SHOWS IDEAL behaviour, i.e., PV=RT which is so only when A=RT and B=0.
46.

Which of the following is an amphoteric hydroxide ?

Answer»

`Be(OH)_(2)`
`Sr(OH)_(2)`
`Ca(OH)_(2)`
`Mg(OH)_(2)`

Solution :`Be(OH)_(2)` amphoteric in NATURE, since it can react both with acid and BASE
`Be(OH)_(2) +2HCl to BeCl_(2) +2H_(2)O`
`Be(OH)_(2) +2NAOH to Na_(2)[Be(OH)_(4)]`
47.

Two minerals that contain Cu are CuFeS_(2) and Cu_(2)S. What mass of Cu_(2)S would contain the same mass of Cu as is contained in 125 lb of CuFeS_(2)?

Answer»


ANSWER :54.2 LB
48.

Which of the following gases would you expect to deviate from ideal behaviur under conditaions of low temperature F_(2),Cl_(2)orBr_(2) ? Explain.

Answer»

Solution :The condition for a GAS to deviate from ideal behavior is high pressure and low temperature. As both conditions greater the DEVIATION from the ideal behaviour. `F_(2),Cl_(2)` and ` Br_(2)` are all non polar molecules. But the heaviestmolecule will have stronger DISPERSION FORCE. Dispersion force increases with molar maas, so `Br_(2)` would deviate most.
49.

What is the entropy change for conversion of one gram of ice to water at 273K and one atmospheric pressure ( Delta _(fus) H = 6.025 kJ mol^(-1)) ?

Answer»


SOLUTION :`Delta_(vap) S = ( 6025J MOL^(-1))/( 273K ) = ( 6025) /( 273xx18) JK^(-1) g^(-1) = 1.23 J K^(-1) g^(-1)`
50.

The stability of 2,3-dimethyl-but-2-ene is more than 2-butene. This can be explained in terms of

Answer»

Resonance
Hyperconjugation
ELECTROMERIC effect
INDUCTIVE effect

ANSWER :B