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.

Solutions of two electrolytes 'A' and 'B' are diluted. The Lambda_(m)of 'B' increases 1.5 times while that of A increases 25 times. Which of the two is a strong electrolyte ? Justify your answer.

Answer»

Solution : Electrolyte B is strong as on DILUTION, the NUMBER of ions remains the same. Only the interionic attraction decreases. THEREFORE the increase in `Lambda_(m)`is small. However in case of A, which is a weak electrolyte, dilution increases the ionization. Therefore `Lambda_(m)`increases much more.
2.

Solutions of two electrolytes A and B each having a concentration of 0.2 M have conductivities 2xx10^(-2) and 4xx10^(-4)" S "cm^(-1) respectively. Which will offer greater resistance to the flow of current and why?

Answer»

SOLUTION :`kappa=Gxx(1)/(a)=(1)/(R)(1)/(a),i.e., kappa PROP(1)/(R)`. Hence, B will OFFER GREATER resistance.
3.

Solutions of two electrolytes 'A' and 'B' are diluted. The Lamda_(m) of 'B' increases 1.5 times while that of A increases 25 times. Which of the two is a strong electrolyte ? Justify your answer.

Answer»

Solution :* Electrolyte .B. is strong as on dilution the number of ions remains the same, only interionic attraction decreases THEREFORE increase in `Lamda_(m)` is small.
* Electrolyte B is strong electrolyte with respect to electrolyte A.
* Electrolyte A is strong, so it gives complete ionization and no dilution, there no significant CHANGE is OBSERVED so, in value of `Lamda_(m)` there will be less difference.
* Electrolyte B is weak, so it does not give complete ionization and on dilution, significant change is observed in number of ions. so, its `Lamda_(m)` value drastically increases (25 times) on dilution. These difference in the value of `Lamda_(m)` is due to increase in the distance between INTER ions which decrease in interionic attaction. "strong electrolyte gives less increase in `Lamda_(m)` on dilution."
4.

Solutions in test tubes containing H_(2)O and aqueous NaOH can be differentiated with the help of

Answer»

red LITMUS
blue litmus
`Na_(2)CO_(3)`
HCL (aqueous)

Solution :`H_(2)O` is neutral while aqueous NAOH is basic . Thus , `H_(2)O` has no effect no red litmus while aqueous NaOH TURNS it blue.
5.

Solutions having same osmotic pressure are called _____

Answer»

SOLUTION :INCREASES
6.

Solutions distilled without change in composition at a temperature are called:

Answer»

Atmorphous
Azeotropic mixture
Ideal solution
Super SATURATED solution

Answer :B
7.

Solutions are of "______________" types

Answer»

three
six
nine
eleven

SOLUTION :THEORY BASED "INTRODUCTION and DEFINITION of solution."
8.

Solution "X" contains Na_(2)CO_(3) and NaHCO_(3) 20 mL of X when titrated using methyl orange indicator consumed 60 mL of 0.1 M of X solution, when titrated using phenolphthalein consumed 20 ml. of 0.1 M HCI solution. The concentrations (in mol L^(-1) ) of Na_(2)CO_(3) and NaHCO_(3), in X are respectively

Answer»

0.01,0.02
0.1,0.1
0.01,0.01
0.1,0.01

Solution :(i) If phenolphthalein is used as indicator for titration of `Na_(2)CO_(3)` with HCl ,the END point is reached only when half of the `Na_(2)CO_(3)` neutralised.
`Na_(2)CO_(3) + HCI rarr NAHCO_(3) + NaCl`
At the end point, there is no reaction between `NaHCO_(3)` and HCI.
Volume of `Na_(2)CO_(3)` = Volume of HCl CONSUMED
20mL of 0.1 M=20mL of 0.1 M
`:.`The concentration of `Na_(1)CO_(3)` in given solution 0.1M
Since only half volume of HCl is consumed for titration of `Na_(2)CO_(3)` at phenolphthalein end point. The remaining half volume of HCI is used for complete NEUTRALIZATION of `Na_(2)CO_(3)` with methyl orange as indicator
`NAHCO_(3) + HCI rarr NaCI + CO_(2)+ H_(2)O`
`:.`Volume of HCI used for complete neutralization of `Na_(2)CO_(3)` in given solution = `2 xx20 ml = 40 ml`
(ii) The remaining HCl used to neutralize `NaHCO_(3)` from the given X solution = 60– 40= 20 ml of 0.1 M From the equation
Volume of `NaHCO_(3)`= Volume of HCl consumed
20 mL of 0.1M = 20 mL of 0.1 M
`:.`The concentration of `NaHCO_(3)`in given X solution = 0.1M
9.

Solution with reserve acidity and lakalinity are called :-

Answer»

Isohydric solution
True solution
Normal soltion
Buffer solution

Answer :4
10.

Solution S_1 contains 3g of urea per litre and solution S_2 contains 9g glucose per litre. At 298 K, the osmotic pressure of

Answer»

`S_1` is GREATER than that of `S_2`
`S_1`is LESS than that of`S_2`
Both the SOLUTIONS is same
Both the solutions is 1 atm.

Answer :C
11.

Solution (s) containing 40 gm NaOH is/are

Answer»

50GM of 80% (w/w) NAOH
50gm of 80% (w/v) NaOH `[d_("SOLN.") = 1.2 gm//m]`
50 gm of 20 NaOH `[d_("soln.") = 1 gm//ml]`
50 gm of 5 m NaOH

Answer :A::C
12.

Solution prepared by dissolving equal number of moles of HOCl (K_(a) = 3.2 xx 10^(-8)) and NaOCl in a buffer of pH

Answer»

3.2 G
`8.0 g`
4.8 g
7.5 g

Answer :D
13.

Solution prepared by dissolving equal number of mole of HOCl ( K_s = 3.2 xx 10^-8) and NaOCl is a buffer of pH :

Answer»

8
3.2
7.5
4.8

Answer :C
14.

Solution of ZnS in dil HCl , when treated with NaOH solution , a white ppt.is formed which dissolves in excess of NaOH due to the formation of :

Answer»

`ZN(OH)_2`
`Zn(OH)Cl`
`Na_2ZnO_2`
`Na_2ZnO_3`.

Solution :`ZnS + 2HCL to ZnCl_2 + H_2S `
`ZnCl_2 + 2NaOH to Zn(OH)_2 + 2NaCl`
`Zn(OH)_2 + underset("EXCESS")(2NaOH) to underset("Sod zincate (soluble)")+ 2H_2O`
15.

Solution of (X) in dil HCI + H_(2)O rarrwhite turbidily (X) overset(H_(2)S//HCI) toback ppt (Y),(Y) is solution in

Answer»

`NAOH`
YAS
`NHO_(3)`
HCI

Answer :C
16.

Solution of sodium metal in liquid NH_3 is strongly reducing due to the presence of :

Answer»

SODIUM atoms
Solvated electrons
NaOH
Spdoum amide

Answer :B
17.

Solution of SO_2 in water is known as:

Answer»

Hydrosulphuric acid
Sulphurous acid
Thiosulphuric acid
Thiosulphurous acid

Answer :B
18.

Solution of following salt on heating with solid K_2Cr_2O_7 and conc. H​_2​SO_​4 orange redvapours are evolved and resultant solution turn aquous NaOH solution yellow

Answer»

NaBr
NaCl
`NaNO_3`
NAI

ANSWER :B
19.

Solution of a salt in sulphanilicacid a naphithylamine give red ppt ,due to

Answer»

`BR^(THETA)`
`I^(Theta)`
`NO_(2)^(Theta)`
`NO_(3)^(Theta)`

ANSWER :b
20.

Solution of a salt in dilute H_(2)SO_(4) or acetic acid produces deep blue colour with starch iodide solution.The salt contains:

Answer»

`Br^(-)`
`I^(-)`
`NO_(3)^(-)`
`NO_(2)^(-)`

Solution :NITRITE ion liberates `I_(2)` from potassium iodide TURNING starch blue.
`2NO_(2)^(-)+3l^(-)+4CH_(3)COOH to I_(3)^(-)+2NOuarr+4CH_(3)COO^(-)+2H_(2)O`
`I_(2)`+starch `to` blue colour
21.

Solution of a salt in dil H_(2)SO_(4) produces deepblue colour with starchiodide solution .The salt contains

Answer»

`BR^(THETA)`
`I^(Theta)`
`NO_(2)^(Theta)`
`NO_(3)^(Theta)`

ANSWER :C
22.

Solution of a salt in dilute H_2 SO_4 produces deep blue colour with starch iodine solution. The salt contains

Answer»

`Br^(-)`
`I^(-)`
`NO_(3)^(-)`
`NO_(2)`

Solution :NITRITE ion LIBERATES `I_(2)` from POTASIUM iodide TURNING starch blue.
23.

Solution of a chemical compound 'X reacts with AgNO_3 solution to form a white ppt. 'Y which dissolves in excess of NH4OH to give complex 'Z'. When Z' is treated with dil HNO_3. Y reappears. The chemical compound 'X' may be :

Answer»

NaBr
NaI
KCL
`CH_3Cl`

ANSWER :C
24.

Solution of a mono basic acid has a pH =5 . If1 mL of it is diluted to 1 litre , what will be the pH of the resulting solution ?

Answer»

3.45
6.96
8.58
10.25

Answer :2
25.

Solution having the same osmotic pressure are called ……………..and they have same…………….. .

Answer»

SOLUTION :ISOTONIC, MOLAR CONCENTRATION
26.

Solution A + solution B rarr Fehling,s reagent. What are A and B ?

Answer»

aq. Copper sulphate, aq. SODIUM potassium tartarate
aq. `AgNO_(3)`, aq. `NH_(4)OH`
aq. `AgNO_(3)`, alkaline sodium POTASIUM tartarate
aq. Copper sulphate, alkaline Sodium potassium tartarate

Answer :D
27.

Solution (A) is ideal and solution (B) is non-ideal with -ve deviation, which of the following are correct?

Answer»

`DeltaH_("mix")=0, DeltaV_("mix")=0` for A
`DeltaS_("mix")` is positive for both A, B
`Delta H_("mix")` is positive, `DEltaV_("mix")` is NEGATIVE for B
`DeltaH_("mix")` is negative, `DeltaV_("mix")` is positive for B

Answer :A::B::C
28.

Solution A contains 7g//L MgCl_(2) and solution B sontains 7g//L of NaCl . At room temperature, the osmotic pressure of

Answer»

SOLUTION A is grater that B
both have same osmotic PRESSURE
solution B is greater than A
Can't determine

Answer :C
29.

Solution 'A' contains acetone dissolved in chloroform and solution B' contains acetone dissolved in carbon disulphide. The type of deviations from Raoult's law shown by solutions A and B, respectively are

Answer»

POSITIVE and positive
positive and NEGATIVE
negative and negative
negative and positive.

Solution :(d): Solution of acetone in CHLOROFORM shows negative deviation and in `CS_(2)` it shows positive deviation from Raoult's law.
30.

Solution A contains 7g/L MgCl_2 and solution B contains 7g/L of NaCl. At room temperature, the osmotic pressure of

Answer»

Solution A is GREATER than B
Both have same OSMOTIC pressure
Solution B is greater than A
Can't determine.

Answer :C
31.

Solution A contains 7g/L of MgCl_(2) and solution B contains 7 g/L of NaCl. At room temperature, the osmotic pressure of :

Answer»

SOLUTION A is greater than B
Both have same osmotic pressure
Solution B is greater than A
Can't determine

Solution :Concentration of NaCl solution `=(7)/(58.5)=0.119 M`
Concentration of `MgCl_(2)` solution `=(7)/(95)=0.074 M`
HENCE, particles (IONS) in NaCl solution
`(B) = 2xx0.119 = 0.238 M`
Hence, particles (ions) in `MgCl_(2)` solution
`(A)=3xx0.074 = 0.222 M`
As the particles in solution B (NaCl) is more than in solution A, the osmotic pressure of solution B will be greater than that of solution A.
32.

Solution (A) containing FeCl_(3) is separated from solution (B) containing K_(4)FE(CN)_(6) by a semipermeable membrane as shown below : {:("Solution (A)","Solution (B)"),(FeCl_(3),K_(4)Fe(CN)_(6)):} In FeCl_(3) on reaction with K_(4)[Fe(CN)_(6)] produces blue colour of Fe_(4)[Fe(CN)_(6)]_(3), the blue colour will appear in

Answer»

A
B
In both A and B
Neither in A nor in B

Solution :As there is only a NET FLOW of solvent from one soltuion to the other through the semi-permeable membrane and there is no flow of solute, the two solute will not come in CONTACT with each other. Hence, no colour will APPEAR in A or B.
33.

Solution A contains 7 g/L MgCl_(2) and solution B contains 7 g/L of NaCl. At room temperature, the osmotic pressure of

Answer»

solution A is greater than B
both have same osmotic pressure
solution B is greater than A
can't determine.

Solution :`7gL^(-1)MgCl_(2)=(7)/(24+71)"mol L"^(-1)`
`=(7)/(95)" mol L"^(-1)=(7xx3)/(95)"mol L"^(-1) " of ions "=0.22M`
`7gL^(-1)NaCl=(7)/(23+35.5)M`
`=(7)/(58.5)M=(7xx2)/(58.5)"mol L"^(-1)" of ions = 0.24 M"`
As concentration of ions in NaCl solution is greater, NaCl soltuion (solution B) will have greater osmotic pressure.
34.

Solution A, B, C and D are respectively 0.1M Glucose, 0.05M NaCl, 0.05M BaCl_2 and 0.1M AlF_3. Which one of the following pairs is isotonic ?

Answer»

A & C
B & C
A & B
A & D

ANSWER :C
35.

Solute when dissolved in water:

Answer»

Decreases the vapour PRESSURE of WATER
Increases the boiling POINT of water
Decreases the FREEZING point of water
All of the above

Answer :D
36.

Solute when dissolve in water

Answer»

increases the VAPOUR PRESSURE of water
decreases the BOILING point of water
decrease the freezing point of water
All of the above

ANSWER :D
37.

Solute A is a ternary electrolyte and solute B is non-electrolyte. If 0.1 M solution of solute B produces an osmotic pressure of 2P, then 0.05 M solution of A at the same temperature will produce an osmatic pressure equal to:

Answer»

P
1.5P
2P
3P

Answer :D
38.

Solubilty product of Mg(OH)_(2),Cd(OH)_(2),Al(OH)_(3) and Zn(OH)_(2) are 4xx10^(-11),8xx10^(-6),8.5xx10^(-23) and 1.8xx10^(-14) resectively. The cation, that will precipitate first as hydroxide, on adding limited quantity of NH_(4)OH in a solution containing equimolar amount of metal cation, is :

Answer»

`Al^(3+)`
`ZN^(2+)`
`MG^(2+)`
`Cd^(2+)`

ANSWER :a
39.

Solubility (s) of CaF_(2) in terms of its solubility product is given as

Answer»

`s = (K_(sp))^(1//3)`
`s = (K_(sp)//2)^(1//3)`
`s = (K_(sp)//4)^(1//3)`
`s = (K_(sp)//2)^(1//2)`

SOLUTION :It is TERNARY electrolyte,
`CaF_(2) harr Ca^(2+) + 2F^(-)`
Let solubility of `CaF_(2)` be s mol `"litre"^(-1)`
Then `{:(CaF_(2) hArr,Ca^(2+),+,2F^(-)),(,s,,2s):}`
Let `K_(sp) = [Ca^(2+)] [F^(-)]^(2) = (s) xx (2s)^(2) = 4S^(3)`
`s = sqrt((K_(sp))/(4))`.
40.

Solubility products of AI(OH)_(3) and An(OH)_(2) are 8.5 xx 10^(-23) and 1.8 xx 10^(-14) respectively. If both AI^(3+) and Zn^(2+) ions are present in a solution, which one will be precipitated first on addition of NH_(4)OH ?

Answer»

`AI(OH)_(3)`
`ZN(OH)_(2)`
Both 1 and 2
None of these

Answer :A
41.

Solubility product of silver bromide is 5.0xx10^(-13). The quantity of potassium bromide (molar mass taken as 120 g " mol"^(-1)) to be added to 1 litre of 0.05 M solution of silver nitrate to start the precipitation of AgBr is

Answer»

`1.2xx10^(-10)g`<BR>`1.2xx10^(-9)g`
`6.2xx10^(-5)g`
`5.0xx10^(-8)g`

Solution :`AgBr HARR Ag^(**) ** Br^(**)`
`K_(sp) =([Ag^(+)][Br^(-)]`
For precipitation to occur
Ionic product `gt` Solubility product
`[Br^(**)]** (K_(sp))/([Ag^(**)])**(5** 10^(-13))/(0.05) 10^(-11)`
i.e. precipitation just STARTS when `10^(-11)` moles of KBR is added to `1//AgNO_(3)` solution
`therefore` Number of moles of `Br^(-)` needed from `KBr=10^(-11)`
`therefore` Mass of `KBr=10^(-11)xx120=1.2xx10^(-9) g`
42.

Solubility product of silver bromide is 5.0 xx 10^(-13). The quantity of potassium bromide (molar mass taken as 120 g mol^(-1)) to be added to 1 litre of 0.5 M solution of silver nitrate to start the precipitation of AgBr is

Answer»

`5.0 xx 10^(-8) G`
`1.2 xx 10^(-10) g`
`1.2 xx 10^(-9) g`
`6.2 xx 10^(-5) g`

Solution :`Br^(-) = (K_(sp)(AGBR))/(C_(AG^(+)))`
`Br^(-) = (5 xx 10^(-13))/(0.05) = 10^(-11)`
Conc. `= [KBr] = 10^(-11)` ltbgt Moles of KBr `= 10^(-11)`
Weight of KBr `= 10^(-11) xx 120 xx 1.2 xx 10^(-9)g`.
43.

Solubility product of Mg(OH)at ordinary temperature is 1.96 xx10^(-11). pH of a saturated soln. of Mg(OH)_2 will be

Answer»

`10.53 `
`8.47`
`6.94`
`3.47`

Solution :`MG(OH)_(2(s)) hArrMg^(2+) +2OH^(-)`
` K_(sp ) =([Mg]^(2+)[OH^(-)]^2)/( [Mg (OH)_2])= 1.96 xx 10^(-11)`
` x xx (2x)^2= 1.96 xx 10^(-11)` ( concentrationofsolid is UNITY )
`4x^3= 1.96 xx 10^(-11)`
` x=((1.96 xx 10^(-11))/(4) )^(1//3)`
` x= ( 4.9 xx 10^(-12))^(1//3)= 1.7 xx10^(-4)`
So ` OH^(-) ` concentration`= 2XX 1.7 xx 10^(-4)`
` i.e.,[OH^-] = 3.4 xx 10^(-4)`
Now `pOH=- log [OH^-]`
`=- log [3.4 xx 10^(-4)]=4- 0.531= 3.469 `
` therefore pH= 14 - 3.469= 10.531`
44.

Solubility product of PbCl_(2) at 298 K is 1.0xx10^(-6). At this temperature solubility of PbCl_(2) in moles per litre is :

Answer»

`(1.0xx10^(-6))^(1//2)`
`(1.0xx10^(-6))^(1//3)`
`(0.25xx10^(-6))^(1//3)`
`(0.25xx10^(-6))^(1//2)`

Solution :Let SOLUBILITY of `PbCl_(2)=x`
`K_(sp)=[Pb^(2+)][Cl^(-)]^(2)=(x)(2x)^(2)=4x^(3)`
`THEREFORE x = ((1.0xx10^(-8))/(4))^(1//3)`
`=(0.25xx10^(-6))1//3`
45.

Solubility product of M(OH), is 10^(-14). What should be the concentration of M^(2+) in 0.1 M solution of NH_(4)OH, if NH_(4)OH gets 10% ionised?

Answer»

`10^(-10)`
`10^(-5)`
`10^(-12)`
`10^(-4)`

Solution :`K_(sp)=[M^(+2)][OH^(-)]^(2)`
`[OH^(-)]=(10)/(100)xx0.1=0.01`
`[M^(+2)]=(K_(sp))/([OH^(-)]^(2))=(10^(-14))/([0.01]^(2))=10^(-10)`
46.

Solubility product of Mg(OH)_(2) at ordinary temp. is 1.96 xx 10^(-11). pH of a saturated of Mg(OH)_(2) will be

Answer»

10.5
8.47
6.94
3.47

Solution :`{:("MG(OH)"_(2(s)),"Mg"^(2+),+,2OH^(-)),(,x,,2x):}`
`K_(sp) = [Mg]^(2+) [ OH^(-)]^(2) = 1.96 xx 10^(-11)`
`x xx (2 x)^(2) = 1.96 xx 10^(-11)` (concentration of solid is unity)
`4x^(3) = 1.96 xx 10^(-11)`
`x = ((1.96 xx 10^(-11))/(4))^(1//3)`
`x = (4.9 xx 10^(-12))^(1//3) = 1.6 xx 10^(-4)`
So, `OH^(-)` concentration `= 2 xx 1.6 xx 10^(-4)`
i.e. `[OH^(-)] = 3.2 xx 10^(-4)`
`= -log [3.2 xx 10^(-4)] = 4- 0.505 = 3.495`
`:. pH = 14 - 3.495 = 10.505`.
47.

Solubility product of Ba(OH)_2 is 4xx10^-9 its solubbility in water is

Answer»

`1XX10^(-3)` M
`1xx10^(-9)` M
`4XX10^(-27)` M
`1xx10^(-27)` M

Answer :A
48.

Solubility product of BaCl_(2) is 4 xx 10^(-9). Its solubility in moles/litre would be

Answer»

`1 XX 10^(-3)`
`1 xx 10^(-9)`
`4 xx 10^(-27)`
`1 xx 10^(-27)`

Solution :`K_(sp) = 4S^(3), S^(3) = (4 xx 10^(-9))/(4) = 10^(-9)`
`:. S = 10^(-3) M`.
49.

Solubility product of AgI at 25^@C is 4xx10^(-18)"mole"^2 //L^2 ​. The solubility of AgI in presence of 2xx10^(-4) M Kl solution at 25^@Cis approximately equal to : (in mol/L)

Answer»

`8xx10^(-8)`
`2XX10^(-16)`
`2xx10^(-14)`
`0.5xx10^(-12)`

Solution :`K_"sp"=[Ag^+][I^-]`
`4xx10^(-18)=[Ag^+]xx2xx10^(-4)`
`[Ag^+] = 2 XX 10^(-14)` M
50.

Solubility product of AgCl is 1 xx 10^(-6) at 298 K. Its solubility in mole "litre"^(-1) would be

Answer»

`1 xx 10^(-6)` mol/ litre
`1 xx 10^(-3)` mol/litre
`1 xx 10^(-12)` mol/litre
None of these

Solution :`{:("For",AgClrarr,Ag^(+)+,Cl^(-)),(,,X,x):}`
`K_(sp) = x^(2), x = sqrt(K_(sp)), sqrt(1 xx 10^(-6)) = 1 xx 10^(-3)` mole/litre.