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 molal depression constant? Does it depend on nature of the solute ?

Answer»

Solution :`K _(f) =` molar FREEZING point DEPRESSION constant or cryoscopic constnat.
`Delta T _(f) = K_(f).m,` where `Delta T_(f)=` depression in freezing point, m = molality of the solution
`K_(f)=` cryoscopic constant
If `m =1, Delta T_(f) = K _(f)`
i.e., cryoscopic constant is equal to the depression in freezing point for 1 molal solution cryoscopic constant depends on the molar concentration of the solute PARTICLES. `K_(f)` is directly proportional to the molar concentration of the solute particles.
`Delta T_(f) = K _(f) xx (W_(B) xx 1000)/( M _(B) xx W_(A))`
`W_(B)=` mass of the solute, `W_(A)=` mass of solvent, `M _(B)=` molecular mass of the solute.
Discussion
2.

Which one among the following does not have the hydrogen bond?

Answer»

LIQUID HCl
Liquid `NH_(3)`
WATER
Phenol

Answer :A
Discussion
3.

Thermally most stable oxide is

Answer»

`Na_(2)O`
`MgO`
`Rb_(2)O`
`K_(2)O`

ANSWER :B
Discussion
4.

Which of the following is // are correct match (i) Photochemical smog: SO_(2) (ii)Nitrate in drinking water : Blue baby syndrome (iii) Phosphate fertilisers in water : BOD level of water increases.

Answer»

only (i)
(i) , and (II)
(i), (ii) and (III)
(i) and (iii)

ANSWER :C
Discussion
5.

The sulphur content of cystine is 26.7%. Given that cystine contains two sulphur atoms, what is the molecular weight of cystine?

Answer»


Solution :Atomic mass of sulphur is 32, hence for TWO sulphur atoms, the molecular formula will have 64g sulphur. THUS, is 26.7 g sulphur, then molecular WEIGHT `= 100g` acid if 64g sulphur is PRESENT molecular weight
`= (100 xx 64)/(26.7) = 239.7 g mol^(-1)`
Discussion
6.

What is Global warming?

Answer»

SOLUTION :The HEATING up of the CARTH through the greenhouse effect is called Global WARMING.
Discussion
7.

The solution having minimum boiling points is

Answer»

` 0.1 M C_6 H_12 O_6`
` 0.1 M CaCl_2`
` 0.1 M NACL`
`0.5 MAlCl_3`

ANSWER :A
Discussion
8.

When 10 g of anhydrous CaCl_(3) is dissolved in 200 g of water, the temperature of the solution rises by 7.7 ^(@) C. Calculate the heat of hydration of CaCl_(2) to CaCl_(2). 6 H_(2)O. Given that the heat of dissolution of CaCl_(2). 6 H_(2)O is 19.08 kJ mol^(-1) . Assume specific heat of the solution to be same as that of water, i.e., 4.184 J g^(-1) K^(-1)

Answer»

Solution :Step I. Calculationof heat of dissolution of anhydrous `CaCl_(2)`
Molar mass of `CaCl_(2) = 40 + 2 xx 35.5 = 111g mol^(-1)`
Heat EVOLVED in dissolved of 10g`CaCl_(2)` in 200 G WATER `=m xx c xx Detla t`
`= 200 xx 4.184 xx 7.7J`
`:. `Heat of dissolutionper mole `=( 200 xx 4.184 xx 7.7) /( 10 ) xx 111 J = 71.52kJ`
i.e,`Delta_("disso.")H ( CaCl_(2)) = - 71.52kJ mol^(-1)`
Step II. Calculation of heat of hydration .
Aim `: CaCl_(2)(s) + 6H_(2)O(l)rarr CaCl_(2).6 H_(2)O(s)`
We have `:`
`Delta_("disso.") H(CaCl_(2))= 71.52kJ mol^(-1) ` ( Calculated above)
`Delta_("disso.") H ( CaCl_(2). 6 H_(2)O) = 19.08 kJ mol^(-1) ` ( Given )
i.e.,`(i)CaCl_(2) (s) + aq rarr CaCl_(2)(aq), DeltaH_(1) = - 71.52kJ mol^(-1)`
(ii) `CaCl_(2). 6 H_(2)O(s) + aq rarr CaCl_(2)(aq), DeltaH_(2) = 19.08kJ mol^(-1)`
Reaction (i) can be written in two steps as `:`
`CaCl_(2)(s) + 6 H_(2)O(l) rarrCaCl_(2). 6 H_(2)O(s) , Delta H - Delta H _(3)`
`CaCl_(2). 6 H_(2) O (s) + aq rarr CaCl_(2)(aq), DeltaH = Delta H _(4)`
`:. Delta H _(3) + Delta H _(4)DeltaH _( 1) = - 71.52 kJ mol^(-1)`
But `DeltaH_(4) = DetlaH _(2) = 19.08 kJ mol^(-1)`
`:. DeltaH _(3) + 19.08 -71.52kJ mol^(-1)`
or `Delta H _(3) = - 90.6 kJ mol^(-1)`
Discussion
9.

Which of the following is/are incorrect about keto-enol tautomerism?

Answer»

Acid catalysed enolisation INVOLVE the INTERMEDIATE carbanion
Racemisation occurs on keeping aqueous solution of carbonyl compounds in which a-carbon is a SYMMETRIC containing ONE enolisable proton
Enol FORM is less stable than keto form in cyclopent-1,2-dione
Keto form is more stable than enol in butan-1,2-dione

Solution :
Discussion
10.

x grams of calcium carbonate was completely burnt in air. The weight of the solid residue formed is 28 g. What is the value of x (in grams)?

Answer»

44
200
150
50

Answer :D
Discussion
11.

trans -Cyclohexane-1, 2-diol can be prepared by the reaction of cyclohexene with

Answer»

`KMnO_(4)`
`OsO_(4)`
Peroxyformic acid
`SeO_(2)`

SOLUTION :Peracids react with alkenes to first form oxides which UNDERGO hydrolysis (acidic or alkaline) by `S_(N)^(2)` mechanism to give trans-1, 2-diol as follows.
Discussion
12.

When CO_(2) is pass through the solution of Ca(OH)_(2), it produce………..

Answer»

`CaCO_(3)`
CAO
`Ca_(2)(OH)_(2)`
`CA(HO_(3))_(2)`

SOLUTION :`Ca(OH)_(2)+CO_(2) to CaCO_(3)`
Discussion
13.

which of the following salt is present in teth?

Answer»

MILK of magnesia
Hydroxyapatite
Barium SUSPENSION
NONE of these

Answer :2
Discussion
14.

Two liquids A and B have vapour pressures 400 mm Hg and 450 mm Hg respectively at a given temperature. Which liquid has higher boiling point?

Answer»

SOLUTION :LIQUID A
Discussion
15.

Which of the following suppresses the decomposition of H_(2)O_(2)

Answer»

`MnO_(2)`
FINELY DIVIDED metals
Acetanilide
DUST particles.

Solution :Acetanilide SUPPRESSES DISSOCIATION of `H_(2)O_(2)`.
Discussion
16.

Which of the two is paramagnetic : V (IV) or V(V) and why ?

Answer»

Solution :Electronic configuration of V(Z = 23) is `[Ar]^(18) 3d^(3) 4s^(2) " " :. V(IV) " is " [Ar]^(18) 3d^(1) and V(V) " is " [Ar]^(18) 3d^(0)` As V (IV) has one unpaired electron, THEREFORE, it is paramagnetic.
Discussion
17.

Which of the following statement(s) are correct? 1. Electronic configuration of Cr is [Ar]3d^(5)4s^(1) (At. No of Cr=24) 2. The magnetic quantum number may have negative value. 3. In silver atom, 23 electron have a spin of one type and 24 of the opposite type (At. No. of Ag=47) 4. The oxidation state of nitrogen in HN_(3) is -3.

Answer»

1,2,3
2,3,4
3,4
1,2,4

Answer :A
Discussion
18.

What is the conc. of H_(2)O_(2) obtained by auto oxidation process?

Answer»

`50%`
`1%`
`30%`
`85%`

ANSWER :B
Discussion
19.

Which elements were discovered by scientist Ramsen and Glenn T Seaborg?

Answer»

Solution :Ramsen : He GIVE same HINT to DISCOVER elements Kr and Xe SUCCESSFULLY.
Glenn T. SEABORG : He discovered element mendelevium having atomic number 101.
Discussion
20.

Water has a higher boiling point than the corresponding hydrides H_(2)S,H_(2)Se and H_(2) Te. This is because water has

Answer»

IONIC BONDS
Hydrogen bonds
Covalent bonds
Van DER WAALS' forces

Answer :B
Discussion
21.

Which of the following metal can form super oxide ?

Answer»

K
RB
CS
All of above

ANSWER :D
Discussion
22.

Which of the following give only meso compound on catalytic reduction ?

Answer»




SOLUTION :
Discussion
23.

What is bon d energy? Give example.

Answer»

Solution :It is defined as..the amount of energy REQUIRED to break one mole of bonds of a particular type in the gasecous state. ..It is also CALLED bond dissociation enthalpy.
Example : C-C bond enthatpy is `348kJmol^(-1)`
Discussion
24.

Transition element exhibit variable valency on account of …… d- orbitals .

Answer»

NORMAL ELEMENTS
METALLIC elements
Transitional elements
Non-metallic elements

Answer :C
Discussion
25.

Which is not correct statement

Answer»

s-block ELEMENTS, except Be and Mg, FORM ionic hydride
Interstitial hydride are nonstoichiometric in nature.
p-block elements form COVALENT hydride
d-,f-block elements form ionic hydride

Solution :Hydrogen atoms occupy the interstitial SPACES of d `&` f block elemnets `&` they form intersitial HYDRIDES.
Discussion
26.

Which of the following will notshow geometrical isomerism ?

Answer»




SOLUTION :Geometrical isomerism is shown by the ALKENES in which DOUBLE bonded carbons must have different atoms or GROUPS. In structure (D), double bonded carbons have 3 groups same and one is different.
Discussion
27.

The volume of gas is reduced to half from its original volume. The specific heat will be

Answer»

reduce to HALF
be doubled
REMAIN constant
increase FOUR times

Solution :The volume of gas is reduced to half from its original volume. The specific heat will be remain constant.
Specific heat is an intensive property which is DEPENDING only on the nature of the gas.
Discussion
28.

The spin quantum number has a value of

Answer»

`1//2`
`+1//2`
`1//2`
EITHER `+1//2 or -1//2`

ANSWER :D
Discussion
29.

Write the relationship between dipole movement and charge.

Answer»

SOLUTION :m=exd (where m= DIPOLE MOMENT, c=charge d=distance)
Discussion
30.

Write reactions to justify amphoteric nature of aluminium.

Answer»

SOLUTION :A substance is called amphoteric if it DISPLAYS CHARACTERISTICS of both acids and BASES. Aluminium dissolves in both acids and bases, showing amphoteric behaviour.
`2Al+6HCl to 2Al^(+3) + 6Cl^(-) + 3H_2`
`2Al + 2NAOH + 6H_2O to 2Na^(+) [Al(OH)_4]^(-) + 3H_2`
Discussion
31.

Who proposed valency bond theory ?

Answer»

SOLUTION :In 1927, Heitlen and LONDON.
Discussion
32.

Which combination of the compounds and their geometry are correct ?

Answer»

`HgCI_(2)` - linear
`CI_F_(3)` -V- shaped
`CIF_(3)` - T- shaped
`ICI_(4)^(-)` square planar

Answer :A::C::D
Discussion
33.

Which of the following is a semi conductor ?

Answer»

C
SI
Ge
both Si and Ge

Answer :D
Discussion
34.

Which of the following occurs reaction intermediate?

Answer»

Free radicals
Carbocations
Carbanions
All

Solution :Reaction INTERMEDIATES are mainly 3-types (+ve)-CARBOCATION `overset(+)(C)`, (-ve) carboanaionc, free radical C
Discussion
35.

What are the shapes of ethyne and methane?

Answer»

SQUARE PLANAR and linear
tetrahedral and TRIGONAL planar
linear and tetrahedral
trigonal planar and linear

Answer :C
Discussion
36.

Which of the following resonating structures is not correct for CO_(2) ? .

Answer»




ANSWER :C
Discussion
37.

The total number of protons in 10 gCaCO_(3) are......

Answer»

`3.011xx10^(23)`
`3.011xx10^(24)`
`3.011xx10^(22)`
`3.011xx10^(25)`

Answer :A::B::C::D
Discussion
38.

Using Dalton's law how will you determine the pressure of a dry gas.

Answer»

Solution :The pressure of dry VAPOR can be calculated unsing DALTON's law
`P_("dry GAS collected")=P_("total")-P_("water vapour")`
`P_("water vapour")` is generally referred as aquesous tension and its values are available for air atvairous temperatures.
Letus understand Dalton's law by SOLVING this Ne, `0.74` mole of AR and `2.5` mole of Xe. Calculate the partial pressure of gases, if the total pressure is 2 atm. at a fixed temperature.
Discussion
39.

Which of the following has no-I power

Answer»

CN
`NO_2`
`-NH_2`
`-OH`

ANSWER :C
Discussion
40.

Which of the following statement(s) is/are correct about benzene?

Answer»

It BURNS with SOOTY flame
it undergoes ELECTROPHILIC substitution reaction
Its resonance energy is `36` kcal `mol^(-1)`
It is HIGHLY unsaturated and decolourises bromine water.

Solution :(A),(B) and (C) are correct statement. (D) is wrong due to DELOCALIZATION of electrons.
Discussion
41.

Which of the following element(s) belongs to halogen group ?

Answer»

`1s^2 , 2s^2 , 2p^6 , 3s^23p^5`
`1s^2 , 2s^2 , 2p^6 , 3s^2 3p^6, 4s^2`
`[AR]3d^10 , 4s^2 4p^5`
`[KR] 4d^10 , 5s^2 , 5p^5`

ANSWER :A::C::D
Discussion
42.

What is the relation between the value of K_c for the forward reaction and value of K'_c for the reverse reaction in the reaction H_(2(g)) + I_(2(g)) hArr 2HI_((g))at equilibrium ?

Answer»

`K'_c=2K_c`
`K_c=2K'_c`
`Kc=K'_c`
`K'_c=1/K_c`

ANSWER :D
Discussion
43.

Which of the following is a Deuterolysis reaction

Answer»

`SO_(3)+D_(2)OtoD_(2)SO_(4)`
`CaC_(2)+2D_(2)OtoCa(OD)_(2)+2ND_(3)`
`Mg_(3)N_(2)+6D_(2)Oto3Mg(OD_(2))+2ND_(3)`
`AlCl_(3)+3D_(2)OtoAl(OD)_(3)+3DCl`

Answer :B::C::D
Discussion
44.

Which of the following is used to remove lignin from woodpulp?

Answer»

Slakedlime
Calcium bisulphate
Unslaked lime
Calcium acetate

Solution :Calcium BISULPHITE is USED to REMOVE lignin from wood PULP leaving behind cellulose for PAPER making.
Discussion
45.

Which of the following show optical isomerism and the isomers can be separated into dextro and laevo forms?

Answer»




ANSWER :A::C::D
Discussion
46.

Write the sulphonation reactions of benzene.

Answer»

Solution :Various products OBTAINED by sulphonation of benzene which depends on CONDITION.

At LOWER TEMPERATURE benzene sulphonic acid and at high temperature BDS (Benzene Disulphonic Acid) is obtained.
Discussion
47.

When excess carbon dioxide gas is passed through an aqueous solution of potassium super oxide a product (X) is formed . The correct statement regarding X is

Answer»

The ANION present in crystalline (X) exist as a dimer due to hydrogen bonds
(X) Cannot be isolated in solid state
(X) is generally CALLED washing soda
Gives THERMALLY unstable CARBONATE on heating

Answer :A
Discussion
48.

Boiling point of water at 750 mm Hg is 99.63^(@)C. How much sucrose is to be added to 500 gor water such that it boils at 100^(@) C ?

Answer»

Solution :Elevation in boiling point required,` Delta T _(b) = 100- 99.63^(@)=0.37^(@)`
Mass of solvent (water)` W_(1)=500g`
Mass of SOULTE, `C_(12) H _(22) O _(11) =342 g mol^(-1)`
Molar mass of solvent `M _(1) = 18 g mol^(-1)`
APPLYING the formula, `M _(2) = (1000 K _(b) W_(2))/(W_(1) XX Delta T_(b))`
`W _(2) = (M_(2) xx Delta T_(b) xx W_(1))/(1000 xx K _(1))`
`= ( 342 mol ^(-1) xx 0.37k xx 500 g )/( 1000 xx 0.52 kg mol ^(-1))= 121. 67g`
Discussion
49.

What is a vapour pressure of liquid ? What is relative lowering of vapour pressure?

Answer»

Solution :The pressure of the vapour in equilibriumwith its liquid is called vapour pressure of the liquid at the given TEMPERATURE
Relative LOWERING in vapour pressure : On addition of a non volatile solute it is observed that the vapour pressure of the solution is LESSER than the solvant ACCORDING to Raolut's LAW relative lowering of vapour pressure is equal to the mole fraction of the solute.
Discussion
50.

What is the shape of a molecule, AB_(2) if it has a definite dipole moment?

Answer»

SOLUTION :The SHAPE of `AB_(2)` is ANGULAR
Discussion