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 meant by the term averge bond enthalpy ? Why is there difference in bond enthalpy of O-H bond in ethanol (C_(2)H_(5)OH) and water ?

Answer»

Solution :All the similar bonds in a molecule do not have the same bond enthaipies ,e.g., in`CH_(4) (H-underset(H)underset(|)overset(H)overset(|)C-H)`, the
four C-H bonds do not have the same bond enthapies because after breaking of the bonds one by one, the
electronic environmentaroundcarbon changes . Hence, the actual bond enthalpy of C-H bond is TAKEN as
the averae value.
O-H bond in ethanol and that in WATER do nothave similar electronic
enviroment around oxygen atom. Hence, their O-H bond enthalpies are DIFFERENT
Discussion
2.

The type of hybridisation takes place in SF_(6) is ………………….

Answer»

SOLUTION :`SP^(3)d^(2)`
Discussion
3.

Which of the following reactions due to the reaction gives -

Answer»

`2CuSO_(4)to4KtoCu_(2)I_(2)+2K_(2)SO_(4)+I_(2)`
`SO_(2)+H_(2)OtoH_(2)SO_(3)`
`CuSO_(4)+4NH_(3)to[Cu(NH)_(3))_(4)]SO_(4)`
`4KCIO_(3)to3KCIO_(4)+KCI`

Answer :C
Discussion
4.

The self ionization constant for pure formic acid, K = [HCOOH_(2^(+))][HCOO^(-)] has been estimated as 10^(-6) a room temperature. What percentage of formic acid molecules in pure formic acid are converted to formate ion? The density of formic acid is 1.22 g//cm^(3).

Answer»

`0.037`
`0.037`
`0.37`
`1.037`

Solution :Give density of FORMIC acid `= 1.22 g//cm^(2)`
weight of fromic acid in 1litre solution
`= 1.22' 10^(3) g`
`:' [HCOOH]= (1.22 XX 10^(3))/(46) = 26.5 M`
`rArr K = [HCOOH_(2)^(+)] = 10^(-6)`
`:' [HCOOH_(2)^(+)] = [HCOO^(-)]`
`rArr [HCOOH]_("dissociated") = 10^(-3)`
`:. (10^(-3))/(26.5) xx 100 = 0.0037`
Discussion
5.

What happens when magnesium is burnt in air ?

Answer»

Solution :Magnesium burns in air with a dazzling light to form MGO and `Mg_(3)N_(2)`.
`2Mg+O_(2) overset("on heating") to 2MgO`
`3Mg+N_(2) overset("on heating")to Mg_(3)N_(2)`
Discussion
6.

When the electron of a hydrogen atom jumps from n = 4 to n = 1 state, the number of spectral lines emitted is

Answer»

15
9
6
3

Solution :`SIGMA (n_(2) - n_(1)) = Sigma (4 -1) = Sigma 3 = 3 + 2 + 1 = 6`
Discussion
7.

Which of the following is true about the element with atomic number 18 ?

Answer»

It has a very LOW IONISATION POTENTIAL
It has a very high electron AFFINITY
Its molecules are monoatomic
Its electroneagtivity is very high

ANSWER :C
Discussion
8.

Which of the following compounds are exhibit tautomerism?

Answer»


ANSWER :B,C,E,G,H can show TAUTOMERISM.
Discussion
9.

The volume of CO_(2) liberated at S.T.P and the quantity of heat energy liberated from the combustion of 2.3 g of ethyl alcohol are C_(2)H_(5)OH(l) +3O_(2)(g) rarr 2CO_(2)(g)+3H_(2)O(l) +1367.2

Answer»

Solution :MOLECULAR weight of `C_(2)H_(5)OH = 46`
46 grams of `C_(2)H_(5)OH` on combustion liberate `2 XX 22.4` lit of `CO_(2)` at S.T.P. and 1367.2 of energy. Volume of `CO_(2)`liberated by the combustion of 2.3 g. of `C_(2)H_(5)OH`
`(2.3)/(46) xx 2 xx 22.4 = 2.24` lit
Energy liberated by the combustion of 2.3 g
`C_(2)H_(5)OH = (2.3)/(46) xx 1367.2 = 68.36 k.j`
Discussion
10.

Which of the following is the most stable ion ?

Answer»

`CH_(3) - CH_(2) - CH_(2) - overset(+)(CH_(2)`
`CH_(3)-CH_(2) - overset(+)(CH)-CH_(3)`
`CH_(3) - underset(underset(CH_(3))(|))overset(+)(C )-CH_(3)`
`overset(+)(CH_(3))`

Answer :D
Discussion
11.

What would be the pH of 0.1 molar sodium acetate solution, given that the dissociation constant of acetic acid is 1.8xx10^(-5).

Answer»


SOLUTION :SODIUM acetate is a salt of weak acid-strong base. Hence,
`pH = 7 + (1)/(2) [ pK_(a)+log c] = 7 + (1)/(2) [- log (1.8xx10^(-5))+log 0.1] = 7 + (1)/(2) [ 4.76xx-1] = 8.88`
Discussion
12.

Which of the following relations gives the value of n =

Answer»

`("MOLECULAR mass ")/("ATOMICMASS ")`
` ("MOLECULARMASS ")/(" Mole mass")`
`("Empirical mass ")/(" Molecular mass ")`
` ("Empiri,mass")/( "Molemass ")`

ANSWER :B
Discussion
13.

Which of the following pairs of elements exhibit diagonal relationship ?

Answer»

Be and Mg
Li and Be
Be and B
Be and Al

Answer :D
Discussion
14.

Which of the following statement (s) about the Modern Periodic Table is are incorrect(i)The elements in the Modern Periodic Table are arranged on the basis of their decreasing atomic number(ii)The elements in the Modern Periodic Table are arranged on the basis of theirincreasing atomic masses(iii)Isotopes are placed in adjoining group (s) in the Periodic Table(iv) The elements in the Modern Periodic Table are arranged on the basis of their increasing atomic number

Answer»

(i) only
(i),(II) and (III)
(i),(ii) and (IV)
(iv) only

Answer :B
Discussion
15.

Which of the following reactions are ot feasible?

Answer»

`HC-=CH+KOHto`
`HC-=CH+NaNH_(2)to`
`HC-=CH+NaOHto`
`HC-=overset((-))(C)K^((+))+(CH_(3))_(3)C-Brto`

Answer :A::C
Discussion
16.

What volume of 1N NaOH solution can completelyconvert a solution containing12g of NaH_(2)PO_(4) to Na_(3)PO_(4)?

Answer»


ANSWER :200ML
Discussion
17.

Which of the following correct regarding the -I effect of the substituents ?

Answer»

`-NR_(2) lt -OR lt -F`
`-NR_(2) GT -OR - lt -F`
`-NR_(2) lt -OR gt -F`
`_NR_(2) gt -OR gt -F`

Solution :As the ELECTRONEGATIVELY of the central atom -I-effect increases, its -I -effect increases accordingly, i.e., `-NR_(2) lt OR lt - F`.
Discussion
18.

Which of the following alkaline earth metal does not react with cold water but water

Answer»

Mg
Be
Ca
Sr

Solution :The ability of REACTION with water INCREASES down the group. Be does not react with water in hot and cold CONDITIONS DUE to less reactivity.
Discussion
19.

When a substance A reacts with water, it produces a combustible gas B and s solution of substance C in water. When another substance D reacts with this solution of C, it produces the same gas B on warming but D can produces gas B on reaction with dilute sulphuric acid at room temperature . A imparts a deep golden yellow colour to a smokeless flame of Bunsen. A,B,C and D respectively are:

Answer»

`NA,H_(2),NAOH, Zn`
`K, H_(2),KOH, Al`
`Ca,H_(2), Ca(OH)_(2), Sn`
`CaC_(2), C_(2)H_(2),Ca(OH)_(2),Fe`

Solution :`underset(A)(2Na) + 2H_(2)O to underset(B)(H_(2))+2ZnO_(2) + underset(C)(2NaOH) and underset(D)(Zn)+underset(C)(NaOH) to Na_(2)ZnO_(2) + underset(B)(H_(2)) underset(D)Zn+ H_(2)SO_(4)("dil.") to ZnSO_(4) + underset(B)(H_(2))`
Since Na gives golden yellow flame, K gives pink violet flame while Ca gives BRICK red flame, therefore, option (a) is correct.
Discussion
20.

Where does electronic configuration takes place in an atom ?

Answer»

<P>

SOLUTION :In ORBITALS LIKE s, p, d, F
Discussion
21.

Which among these is not associated with aliphatic compounds

Answer»

theycontain (4n+2) electrons
they contain straightchain compounds
they containbrached chain compound
they have APPROPRIATE NUMBER of g atoms and unctional GROUPS

Answer :a
Discussion
22.

The sharp melting point of crystalline solids is due to ……..

Answer»

a REGULAR ARRANGEMENT of consitituent particles observed over a short DISTANCE in the crystal lattice .
a regular arrnagment of constituent particlesobserved over a LONG distance in the crystal lattice.
same arrangementof consitituent particles in different direction.
different arrangement of constituent particles in different DIRECTIONS.

Answer :A
Discussion
23.

What is the composition of Zeigler Natta Catalyst?

Answer»

SOLUTION :Tiethylaluminium and TITANIUM TETRACHLORIDE INERT SOLVENT.
Discussion
24.

What is the effect of pressure on gas dissolve in liquid ?

Answer»

SOLUTION :As PRESSURE INCREASE SOLUBILITY increase.
Discussion
25.

Write the IUPAC names of (i) CH_(2) = CHCl (ii) CH_(2) = CH- CH_(2) Br

Answer»

Solution :`(i) CH_(2) = CHCL` : CHLOROETHENE
(ii) `CH_(2) = CH - CH_(2) Br : 3`- BROMO- prop-1-ene
Discussion
26.

Using s, p, d, f notations, describe the orbital with the following quantum numbers (a) n=2, l = 1 (b) n = 4, l = 0 (c) n = 5, l = 3 (d) n = 3,l = 2.

Answer»

SOLUTION :
Discussion
27.

Which of the following compound is/are react with Na metal & liberate hydrogen gas

Answer»

`CH_(3)-OH`
`CH_(3)-C-=CH`
`Ph-OH`

ANSWER :A::B::C
Discussion
28.

Which can be purified by crystalization ?

Answer»

PHENOL
CANE sugar
Benzoic ACID
ACETANILIDE

Solution :Cane sugar purified by cryctallisation.
Discussion
29.

What is the shape of methane molecule?

Answer»

Squareplaner
Pyramidal
Totrahedral
Octahedral

Answer :C
Discussion
30.

What will be the molality of the solution made by dissolving 10g of NaOH in 100g of water?

Answer»

2.5 m
5 m
10 m
1.25m

Solution :Molarity(m)`=("Weight of solute")/("MOLAR weight of solute")XX(1000)/("Weight of SOLVENT")`
Discussion
31.

Which of the following graphs is correct for a reaction?

Answer»




Solution :SLOPE = `(-DELTAH^(@))/(R)`
`:.` exothermic `implies` ,+, ve slope
ENDOTHERMIC `implies` .-. ve slope
Discussion
32.

Which of the following reagents are used to give blue ring test of solution of Na_(2)S_(2)O_(3)?

Answer»

`(NH_(4))_(2)MoO_(4)`
`CuSO_(4)`
CONC. `H_(2)SO_(4)`
`[Ni(EN)_(3)] (NO_(3))_(2)`

Answer :A::C
Discussion
33.

What will be the conjugate bases for the Bronsted acids :HF, H_2SO_4 and HCO_3^-

Answer»

SOLUTION :CONJUGATE BASE : `F^(-) , HSO_4^(-)` and `CO_3^(2-)`
Discussion
34.

Write the dimeric structure of Aluminium chloride.

Answer»

SOLUTION :
Discussion
35.

What is the relation between standard free energy change and equilibrium constant ?

Answer»

`DeltaG^(@)=+"RT LN K"`
`k=-DeltaG^(@)RT`
`DeltaG^(@)=-lnk`
`k=RTDeltaG`

ANSWER :A
Discussion
36.

Which of the following pair contains with same structures.

Answer»

Borazine & BENZENE
Biborane & HYDRAZINE
NaCl & NFO
Grphite & Boran nitride

Solution :Diborane having bridge HYDROGEN BONDING and hydrozine doesnot have.
Discussion
37.

Which of the following metals are not detected by flame test?

Answer»

Be and MG
Ba and Ca
Sr and Ca
Mg and Ca

Solution :`e^(-)`of Mg and Be are so strongly BONDED, so they COULD not GET exited in flame.
Discussion
38.

Which of the following is environmental friendly reaction

Answer»

A + B `RARR` C (wanted)
HOCI (g) `overset(vartheta)(rarr) OH + CL(g)`
`CF_(2) CI_(2) (g) overset(vartheta)(rarr) Cl(g) + CF_(2) - Cl(g)`
`NO + O_(3) overset("STRATO sphere")(rarr) NO_(2) + O_(2) `

Answer :A
Discussion
39.

What happen when diborane is heated with ammonia ?

Answer»
Discussion
40.

What weight of non-volatile solute (urea) NH_(2) CO NH_(2) needs to be dissolved in 100 g of water in order to decrease the vapour pressure of water by 25%. What will be the molality of solution?

Answer»


ANSWER :[13.88 m]
Discussion
41.

Which of the following dienophiles is the most reactive in normal Diels-Alder reactions?

Answer»




Solution :The dienophile with an electron-donating SUBSTITUENT (with the least LOW LUMO) is least REACTIVE
Discussion
42.

Which of the group given below is most appropriate for the hydride compounds ?

Answer»

s-block - METALLIC hydride - `TiH_2`
p-block - MOLECULAR hydride -`CH_4`
d-block - Metallic hydride - `BeH_2`
f-block Ionic hydride -`TiH_2`

Answer :B
Discussion
43.

When brine solution is electrolysed then nature of solution will be?

Answer»


ANSWER :BASIC
Discussion
44.

Which of the following is a primary pollutant?

Answer»

Sulphuric ACID
acrolein
formaldehyole
Carbon monoxide

ANSWER :D
Discussion
45.

The stablest radical among the following is

Answer»

`C_(6)H_(5)-OVERSET(*)(C)H-CH_(3)`
`CH_(3)-overset(*)(C)H-CH_(3)`
`C_(6)H_(5)CH_(2)overset(*)(C)H_(2)`
`CH_(3)CH_(2)overset(*)(C)H_(2)`

SOLUTION :STABILIZED by +I effect or hyperconjugation effect of the `CH_(3)` group and resonance effect of the `C_(6)H_(5)` group.
Discussion
46.

Write the IUPAC names of the given poly functiona compounds (a) HOCH_(2)CH_(2)CH_(2)COOH (b) (CH_(3))_(2) CH overset(overset(O)(||))(C )CH_(2)COOCH_(3) (c ) CH_(3)CH(NH_(2))CH_(2)CH_(2)CH(OH)CH_(2)CH_(3) (d) CH_(3)OCH_(2)COCH_(3) (e ) CH_(2)CHBrCH_(2)CONHCH_(2)CH_(3)

Answer»


Answer :(a) 4 - Hydroxybutanoic ACID;
(B) Methyl-4-methyl-3-oxopentanoate;
(C ) 6-Amino-3-heptanol;
(d) Methoxypropanone;
(E ) Bromo-N-ethylbutanamide
Discussion
47.

Which hybridization is possible with d orbitals ? And which are not possible ? Explain.

Answer»

Solution :The elements PRESENT in the THIRD period contain d orbitals in addition to s and p orbitals.
The hybridization is possible between less energy difference containing nearer orbital.
(i) The energy of the 3d orbitals are comparable to the energy of the 3s and 3p orbitals. So, hybridization involving 3s, 3p and 3d orbitals is possible.
(ii) The energy of the 3d orbitals are comparable of the energy of the 4s and 4P orbitals. So, hybridization involving 3d, 4s and 4p orbitals is possible.
SINCE the difference in energies 3p and 4s orbitals is SIGNIFICANT, no hybridization involving 3p, 3d and 4s orbital is possible.
Discussion
48.

Write note on Metallic or non stoichiometric hydrides.

Answer»

Solution :The Metallic hydride are formed by many d -block and f-block elements.
However, the metals of group 7, and 9 do not form hydride. Even from group 6, only chromium forms CrH. These hydrides conduct heat and electricity THOUGH not as efficiently as their parent metals do.
Unlike SALINE hydrides, they are almost always non-stoichiometric, being deficient in hydrogen.
For example : `LaH_(2.87), YbH_(2.55),TiH_(1.5-1.8),ZrH_(1.3-1.75), VH_(0.56), NiH_(0.6-0.7), PdH_(0.6-0.8)` etc. In such hydrides, the law of constant composition does not hold good.
In these hydrides, hydrogen occupies interstitial SPACE in the metal lattice producing distortion without any change in its type. Consequently, they were termed as interstitial hydrides.
The except for hydrides of Ni, Pd, CE and Ac, other hydrides of this class have lattice different from that of the parent metal.
The PROPERTY of absorption of hydrogen on transition metals is widely used in catalytic reduction / hydrogenation reactions for the preparation of large number of compounds.
Some of the metals (e.g., Pd, Pt) can accommodate a very large volume of hydrogen and, therefore, can be used as its storage media.
This property has high potential for hydrogen storage and as a source of energy.
Discussion
49.

Which one of the following is used for producing pesticides?

Answer»

`CHI_3`
`CHCl_3`
`C Cl_3NO_2`
`C Cl_4`

SOLUTION :`CHCl_3`
Discussion
50.

What is inversion temperature?

Answer»

SOLUTION :The TEMPERATURE below which a GAS obey Joule-Thomson effect is called inversion temperature
`(T_i). TI=(2a)/(Rb)`
Discussion