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 pH of a solution obtained by dissolving 0.0005 mole of the strong electrolyte, calcium hydroxide, Ca(OH)_(2) , to form 100 ml of a saturated solution (aqueous)? (K_(w)=1.0xx10^(-14) "mole"^(2) "litre"^(-2))

Answer»

`9.8`
` 11.7`
` 12.0 `
` 3.0 `

Solution :` M= ( 5 XX 10 ^(-4) )/(100)xx 1000 = 5 xx 10 ^(-3) `
` THEREFORE N= M xx n = 0.01 M`
` [OH^(-)] =10 ^(-2)N rArr pOH =2rArr pH =12`
Discussion
2.

What indicate the value of K_a ? What is its dimension ?

Answer»

Solution :`K_a` is KNOWN as DISSOCIATION constant of weak ACID. `K_a` is dimension LESS.
Discussion
3.

What do you understand by bond pairs and lone pairs of electrons ? illustrate by giving one example of each type.

Answer»

Solution :Bonding ELECTRON pair : In molecule the electron pair which FORM bond between two atom is CALLED bonding electron pair.
Nonbondlng electron pair : The electron pair which does not take PART in bond formation in molecule is called non bonding electron pair :
eg. Lewis structure of `H_(2)O, `
Discussion
4.

What type of isomerism is shown by the But-1-yne and But-2-yne?

Answer»


ANSWER :POSITION ISOMERISM
Discussion
5.

Which of the following ions will cause hardness in water ?

Answer»

`CA^(2+)`
`Na^(+)`
`CL^(-)`
`K^(+)`

Answer :A
Discussion
6.

What is temporary hardness of water? How is it removed?

Answer»

Solution :Temporary hardness of WATER is due to the presence of soluble bicarbonates of magnesium and calcium. By heating / boiling, these salts decomposed into insoluble carbonate and hydroxide, respectively. The RESULTING precipitates can be removed by filtration. `Ca(HCO_(3))_(2)_(aq)toCaCO_(3(s))+H_(2)O_((l))+CO_(2(g))`
`Mg(HCO_(3))_(2)_(aq)toMg(OH)_(2(s))+CO_(2(g))`
Discussion
7.

Two isomer of butane are n-butane and iso butane……… is the relation of no. of sigma and pi bond in it.

Answer»


ANSWER :EQUAL
Discussion
8.

Which of thefollowing will produce a buffer solution when mixed in equal volumes ?

Answer»

0.1 MOL `dm^(-3) NH_(4)OH` and 0.1 mol `dm^(-3)` HCl
0.05 mol `dm^(-3) NH_(4)OH` and 0.1 mol `dm^(-3)` HCl
0.1 mol `dm^(-3) NH_(4)OH` and 0.05 mol `dm^(-3)` HCl
0.1 mol `dm^(-3) CH_(3)CO ON a` and 0.1 mol `dm^(-3)` NaOH

Solution :In (C), all HCl will be neutralized and `NH_(4)Cl` will be formed. Also some `NH_(4)OH` will be left unneutralized. Thus, the final solution will contain `NH_(4)OH and NH_(4)Cl` and hence will form a BUFFER.
Discussion
9.

What is buffer solutions ? Explain types of buffer solutions by examples.

Answer»

Solution :DEFINATION : The solutions which resist change in pH on dilutionor with the addition of small amounts of acid or ALKALI are called Buffer solutions. Buffer solutions are two types like acidic and basic.
(A)Acidic buffer solutions : The pH value of this solutions is less than 7.0 . The examples of acidic buffer as under.

pH of a acidic buffer is CALCULATE as following :
pH=`pK_a + log "[Salt]"/"[Acid]"`...(Eq.-i)
`pH=pK_a + "log" (["Conjugate base" A^-])/"[Acid HA]"`....(Eq.-ii)
In it `[H_3O^+]=K_a ([HA])/([A^-])` ....(Eq.-iii)
This equation is KNOWN as Henderson Hasselback equation . Here weak acid HA is ionised in less amount.
(B) Basic buffer solutions : The pH value of buffer solutions is more than 7.0 is known as basic buffer solution . Basic buffer is formed by mixing of weak base and its salt of strong acid. Examples of basic buffer :

pH of basic buffer is calculate by following :
`pH=pK_w`-(`pK_b` + log salt/base) ...(Eq.-i)
pH=`pK_a - "log" (["Conjugate acid" BH^+])/"[Base B]"`....(Eq.-ii)
pOH=`pK_b+"log" (["Conjugate acid" BH^+])/"[Base B]"` ...(Eq.-iii)
`=pK_b+ "log" "[Salt]"/"[Base]"`
...(Eq.-iv)
The pH of buffer solution after dilution does not change as the ratio of exponent factor remain unchange.
Discussion
10.

Which of the thermodynamic properties out ofE,S,T,P,V,H and G are intensive propertiesand why ?

Answer»

SOLUTION :T and PARE intensive propertiesbecause they DEPEND only UPON the NATURE of the substance.
Discussion
11.

Which of the following redox reaction is oxidation and which is reduction? Cl_2+2e^(-)to2Cl^(-)

Answer»

SOLUTION :REDUCTION
Discussion
12.

Which one of the following exhibits geometrical isomerism ?

Answer»

1,2-dibromopropene
2, 3-dimethylbut-2-ene
2, 3-dibromobut-2-ene
2-methylbut-2-ene

Answer :A::C
Discussion
13.

Why a non- spontaneous reaction becomes spontaneous when coupled with a suitable spontaneous reaction ?

Answer»

Solution :The OVERALL FREE ENERGY change for the coupledreaction is NEGATIVE.
Discussion
14.

What is the osmotic pressure of the solution obtained by mixing 300 cm^(3) of 2% (mass-volume) solution of urea with 300 cm^(3) of 3.43 % solution of sucrose of 20^(@)C ? (R = 0.082 "L atm K"^(-1) "mol"^(-1))

Answer»

5 ATM
5.2 atm
2.6 atm
4.5 atm

Solution :`piV=[((w_(B))/(m_(B)))_(urea)+((w_(B))/(m_(B)))_("sucrose")]RT`
`pixx(600)/(1000)=[(6)/(60)+(3xx3.42)/(342)]0.082xx293`
`pixx0.6=(0.1+0.03)xx0.082xx293`
`pi=5.2`atm]
Discussion
15.

Typical features of E2 involve :

Answer»

TWO step reaction
Second step is the rate DETERMINING step
Anti-periplanar transition state
Formation of a CARBANION INTERMEDIATE, stabilized by conjugation with a strong -M group.

Solution :It is basic fact.
Discussion
16.

When reaction is at standard state at equilibrium, then

Answer»

`80%`
`87%`
`90%`
`97%`

Solution :Precentage efficiency of the fuel cell `=(DeltaG)/(DeltaH)XX100` . The concerned reaction is
`CH_(3)OH(l)+(3)/(2)O_(2)(g)rarrCO_(2)+2H_(2)O(l)`
`DeltaG_(r)[DeltaG_(f)(CO_(2),g)+2DeltaG_(f)(H_(2)O,l)]`
`[-DeltaG_(f)(CH_(3)OH,l)-(3)/(2)DeltaG_(f)(O_(2),g)]`
`=-394.4+2(-237.2)-(-166.2)-0`
`=-394.4-474.4+166.2=-702.6KJmol^(-1)`
Percentage effieiency `=(702.6)/(762)xx100=96.78%=97%`
Discussion
17.

When a solution of alkaline earth metalin liquid ammonia is evaporated:

Answer»

They from hexammoniates, `M(NH_(3))_(6)`
The ammoniates decompsde at high temperatures
The tendency to from ammoniates decreases with increase in the SIZE of the metal
The ammoniates are good CONDUCTORS of ELECTRICITY

Answer :A::B::C::D
Discussion
18.

Which out of Na, K, Mg occurs as oxide in nature?

Answer»

Solution :AI OCCURS as oxide in NATURE as BAUXITE `AI_(2)O_(3). 2H_(2)O`
Discussion
19.

The standard free energy of a reaction is found to be zero. What is its equilibrium constant ?

Answer»

SOLUTION :`DeltaG^(@)= - 2.303 RT LOGK `. Hence, log `K = 0` or`K =1 `.
Discussion
20.

Which of the following pairs of ions is isoelectronic as well as isostructural ?

Answer»

`CO_(3)^(2-),NO_(3)^(-)`
`ClO_(3)^(-),CO_(3)^(2-)`
`SO_(3)^(2-),NO_(3)^(-)`
`ClO_(3)^(-),SO_(3)^(2-)`

Solution :`CO_(3)^(2-)` ion has 32 electrons `(6+3xx8+2)` and C is `sp^(2)` hybridized. `NO_(3)^(-)` has 32 electrons and N is ALSO `sp^(2)`-hybridized. Thus, `CO_(3)^(2-)andNO_(3)^(-)` are isoelectronic as well as isostructural, i.e., OPTION (a) is CORRECT.
`CO_(3)^(-)` ionhas 42 electrons `(17+3xx8+1)` and Cl is `sp^(3)`-hybridized, while `SO_(3)^(2-)` also has 42 electrons and S is `sp^(3)`-hybridized. Thus, `ClO_(3)^(-)andSO_(3)^(2-)` are also isoelectronic and isostructural, i.e., option (d) is correct.
Discussion
21.

Which of the following hydrocarbons has thelowest dipole menent ?

Answer»


`CH_(3) -=C CH_(3)`
`CH_(2)CH_(2) C-=CH`
`CH_(2) -=CH - C -= CH`

Solution : It is symmetrical and LINEAR .
Discussion
22.

Which of the following reaction is expected to give readily a hydrocarbon product in good yields ?

Answer»

`RCOOK overset("Electrolysis")RARR`
`RCOO AG overset(I_(2))rarr`
`CH_(3)CH_(3) overset(Cl)rarr`
`(CH_(3))_(2) C Cl_(2) overset(C_(2)H_(5)OH) rarr`

Solution :`2RCOCK + 2H_(2)O`
`overset("Electrolysis")rarr underset("Alkane")(R - R) + CO_(2) + H_(2) + 2KOH`
Discussion
23.

The total vapoure pressure of a 4 mole% solutionof NH_(3) in water at 293 K is 50.0 torr. The vapour pressure of pure water is 17.0 torr at this temperature . Applying Henry's and Raoult's laws, calcilate the total vapour pressure for a 5 mole%solution:

Answer»

58.25 torr
33 torr
42.1 torr
52.25 torr

Answer :a
Discussion
24.

What are organic reactions ?

Answer»

Solution :Substrate is an ORGANIC MOLECULE REACTS with reagent , which may be an organic , in organic or any agnet like heat PHOTON etc , that brings about the chemical change to form a PRODUCT, this is known as organic reactions .
Discussion
25.

What is the acidity order of x,y & z ?

Answer»

` X GT y gt Z`
`x gt z gt y`
`y gt z gt x`
`z gt y gt x`

ANSWER :A
Discussion
26.

Which is the hybridisation of 1, 2, 3 carbon in overset(3)(C )H_(3)- overset(2)(C )-= overset(1)(C )H ?

Answer»

`SP^(3), sp^(2), sp`
`sp, sp, sp^(3)`
`sp^(2), sp^(2), sp^(3)`
`sp, sp^(3), sp^(3)`

ANSWER :B
Discussion
27.

Two alkenes X(91%"yield") and Y(9% yield) are formed when the following compound is heated The structures of X and Y, respectively are

Answer»




ANSWER :C
Discussion
28.

Three samples of water A, Band C have the D.O levels of 4 ppm, and 3.8 ppm and 2.1 ppm respectively the most polluted sample of water is

Answer»

can not be PREDICTED
B
C
A

Answer :C
Discussion
29.

Which of the following is not the effect of acid rain

Answer»

The GLOSSY NATURE of Tajmahal is affected
The PH if the soil increases.
Historical monuments of Rome are affected
Soil fertility decreases.

ANSWER :B
Discussion
30.

Which of the following statements is/are correct ?

Answer»

Spiro compounds contain fused rings at quarternary carbon
Bicyclo compounds contain two rings connected by bridge
Bicyclo compounds can be BRIDGED or fused.
LOWER CYCLIC ALKYNES are unstable.

Solution :All are CORRECT statements.
Discussion
31.

The total no. of possible dichloro derivatives of isobutene are :

Answer»

2
4
5
6

Solution :
Discussion
32.

Write resonance structures of CH_(3)COO^(-) and show the movement of electrons by curved arrows

Answer»

Solution :(i) First write the structure and put unshared pairs of valence electrons on appropriate atoms.
(ii) Then draw the arrow ONE at a TIME MOVING the electrons to get the other structures.
(III) `CH_(3)COO^(-)` is a `CH_(3) - overset(overset(O)(||))(C )- O^(-)` and its two resonance structure are as under
Discussion
33.

Which of the following statement are correct for give reaction. CH_3-undersetunderset(CH_3)(|)C=CH-CH_3+HBr overset("Peroxide")toCH_3-undersetunderset(CH_3)(|)oversetoverset(Br)(|)C-CH_2-CH_3 " " CH_3-undersetunderset(CH_3)(|)CH-oversetoverset(Br)(|)CH-CH_3

Answer»

MAJOR PRODUCT is mixture of two enantiomers.
Less stable carbocation give major product
Less stable FREE RADICAL give major product
Morestable free radical give major product

Answer :A::D
Discussion
34.

Which buffer solution has maximum pH?

Answer»

mixture which is 0.1 M in `CH_3 COOH and 0.1 Mis CH_3 COONa [pK_a (CH_3COOH )= 4.74`
mixture which is `0.2 M CH_3 COOH and 0.2 M is CH_3 COONa`
mixture which is `0.1 M ` in ` NH_4 Cl and 0.1 M `in `NH_4 OH [pK_a (NH_4^(+)) =9.26]`
all the solution have EQUAL pH which is `4.74`

Solution :( a ) ` pH =pKa +log ""(0.1)/(0.1)=4.74`
( B ) ` pH =pKa +log ""(0.2)/(0.2)=4.74`
( C ) ` pH =pKa +log ""(0.1)/(0.1)=9.26`
Discussion
35.

Which of the following is formed when lithium is heated in air ?

Answer»

Only `Li_(2)O`
Only `Li_(3)N`
Both `Li_(2)O and LiN_(3)`
Both `Li_(2)O and Li_(3)N`

Answer :D
Discussion
36.

The uncertaintyin positionis 10^(-10)m andin velocityis 5.27 xx 10^(-24) ms^(-1)calculatemass of particle .

Answer»

SOLUTION :`1XX 10^(10) M`
Discussion
37.

The relation between K_(p) and K_(c) is K_(p)=K_(c)(RT)^(Deltan) unit of K_(p)=(atm)^(Deltan), unit of K_(c)=(mol L^(-1))^(Deltan) Consider the two reaction: XeF_(6)(g)+H_(2)O(g) hArr XeO_(3)F_(4)(g)+2HF(g), K_(1) XeO_(4)(g)+XeF_(6)(g) hArr XeOF_(4)(g)+XeO_(3)F_(2)(g), K_(2) Then the equilibrium constant for the following reaction XeO_(4)(g)+2HF(g) hArr XeO_(3)F_(2)(g) is given by:

Answer»

`K_(1)//K_(2)^(2)`
`(K_(1)//K_(2))^(1//2)`
`K_(1)^(2)//K_(2)^(3)`
`K_(2)//K_(1)`

SOLUTION :`K=K_(2)/K_(1)`
Discussion
38.

The total number of fundamental particles in normal hydrogen molecule

Answer»

1
2
3
4

Answer :D
Discussion
39.

Write the coordination number of each ion in the following crystals .(i) NaCl (ii) CsCl (iii) ZnS (iv)CaF_(2) ( v)Na_(2)O

Answer»

SOLUTION :`Na^(+) = 6, CL^(-) =6 , (ii) CS^(+) = 8, Cl^(-) = 8 (iii) Zn^(2+) = 4, S^(2-) = 4(iv) Ca^(2+) = 8, F^(-) = 4 , (V) Na^(+) = 4, O^(2-) = 8 `
Discussion
40.

Which elements are exception in classification of periodic table.

Answer»

Solution :Two elements like hydrogen and helium are observed as an exception .
Place of hydrogen in periodic table :
Hydrogen contain le in ls orbital so it must be situated in group-1.
Hydrogen ACCEPT `1 e^(-)`and from stable structure like helium.
So, it must be situated in group-17
But there is same DIFFERENCE observed between hydrogen and ist group and hydrogen and `17^(th)`group so hydrogen atom is situated in separately in periodic table.
Place of helium in periodic table .
Helium element having `1 ^(ST)`electron configuration so it must be present in s-block.
But its positioning in the p-block along with other group 18 elements is Justified.
Because it has a completely filled valence shell `(1 s^(2))` and as a RESULT, exhibits properties CHARACTERISTIC of other noble gases.
Discussion
41.

What is oxidation number of N inunderlineNH_(4)underlineNO_(3) respectively ?

Answer»

`-3,+3`
`+1,-1`
`-3,+5`
`+3,-5`

SOLUTION :`NH_(4)NO_(3)toNH_(4)^(+)+NO_(3)^(-)`
Discussion
42.

Thermodynamically the most stable form of carbon is ……

Answer»

DIAMOND
GRAPHITE
fullerenes
coal

Answer :B
Discussion
43.

What is ionic equilibrium ? Discuss the relation of types of substance and ionic equilibrium in solution.

Answer»

Solution :The ions of aqueous solution in equilibrium its known as ionic equilibrium.
e.g. `Fe_((aq))^(3+) + SCN_((aq))^(-) hArr [Fe(SCN)]_((aq))^(2+)`
The aqueous solution of sugar does not conduct electricity and sugar is .non-electrolytic.. The ionic equilibrium is not occurs in non electrolytic substance.
However, when common salt is added to water it conducts electricity. The substances conduct electricity in their aqueous solutions are called electrolytes STRONG electrolytes on dissolution in water are ionized almost completely.
The salt which is almost 100% ionization in water is called strong ELECTROLYTE. e.g. NaCl is strong electrolyte. This type of solution ionic concentration and conductivity is more.
The substance less ionised (less than 5%) in solution is known as weak electrolyte. e.g., Acetic ACID. "In weak electrolytes, equilibrium is established between ions and the unionized molecules."
e.g. `CH_3COOH_((aq))+aq hArr CH_3COO_((aq))^(-) + H_((aq))^(+)`
Ionic equilibrium is established in Acid, Base and SALTS.
Discussion
44.

What happens when calcium nitrate is heated ?

Answer»

Solution : Calcium nitrate, on HEATING, decomposes to GIVE calcium OXIDE.
`2CA(NO_(3))_(2(s)) overset(Delta)to 2CaO_((s)) +4NO_(2(g))+O_(2(g))`
Discussion
45.

Which of the following does not represent the resonating structure of biphenyl

Answer»




SOLUTION :ONE CATION and one ANION
Discussion
46.

Which of the following is nature ore name of calcium

Answer»

HYDROLITH
Colemanite
Artinite
Phosphorate

Solution :Arinite `MgCO_(3).MG(OH)_(2).3H_(2)O`
Hydrolith `CaH_(2)`
Colamanite `2Cao.3Ba_(2).5H_(2)O`
Phosphorite `Ca3(PO_(4))_(2)`
Discussion
47.

Which among the following is the heaviest?

Answer»

One MOLE of oxygen
One molecule of sulphur trioxide
100 MOLES of hydrogen
44 G of carbon dioxide

Answer :C
Discussion
48.

What is mean by stock solution (or) standard solution ? what is meant by working standard?

Answer»

Solution :(i) A standard solution or a STOCK solution whose concentration is accurately KNOWN.
(II) At the time of experiment, the solution with required concentration is prepared by DILUTING the stock solution. This diluted solution is called working standard.
Discussion
49.

Which of the following is not ferromagnetic ?

Answer»

Cobalt
Iron
Manganese
Nickel

Solution :MAGANESE in not FERROMAGNETIC.
Discussion
50.

Write the IUPAC names of the following compounds. (i) CH_(3)-CH_(2)-CH_(2)-NH-CH_(3) (ii) CH_(3)-underset(CH_(3))underset(|)(CH)-NH-CH_(3) (iii) CH_(3)-CH_(2)-CH_(2)-underset(CH_(3))underset(|)N-CH_(3)

Answer»

SOLUTION :(i) N-methylpropan-l-amine (II) N-methylpropan-2-amine
(III) N,N-dimethylpropan-1-amine
Discussion