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.

Sample containing ""_(88)^(234)Ra, which decays by alpha-particle emission, is observed to disintegrate at the following rate expressed as counts per minute (cpm). Calculate half-life of this nuclide. t=0,1000 cpm, t=1h, 992 cpm, t= 10h, 924 cpm, t=100h, 452cpm, t= 250h, 138 cpm

Answer»


ANSWER :3.63 DAYS
2.

Sample of 2, 3-dibromo-3-methylpentane is heated with dust. The resulting product is isolated and heated with HI in presence of phosphorus. Indicate which is the structure represent the final organic product formed in the reaction

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`CH_3-CH_2-underset(CH_3)underset|CH-CH_2-CH_3`
`CH_2=CH-overset(CH_3)overset|CH-CH_2-CH_3`
`CH_3-CHI-undersetunderset(CH_3)|CH-CH_2-CH_3`
`CH_2-CH-undersetunderset(CH_3)|C(I)-CH_2-CH_3`

SOLUTION :
3.

Same quantity of electricity was passed through solutions of salts of elements A,B and C with atomic weights 7, 27 and 48 respectively. The masses of A,B and C deposited were 2.1 g,27.7g and 7.2 respectively. The valencies of A,B and C respectively are

Answer»

3,2 and 1
1,2 and 3
1,3 and 2
2,3 and 2

Solution :Suppose valencies of A,B and C are a,b, and c respectively. Then their EQUIVALENT weights will be (At. Wt/valance) 7/a,27/b and 48/c. when same quantity of electricity is passed, masses DEPOSITED are in the ratio of their equivalent weights, i.e.,
`("Mass of A")/("Eq. wt. of A")=("Mass of B")/("Eq. wt of B")=("Mass of C")/("Eq. wt of C")`
`therefore(2.1)/(7//a)=(2.7)/(27//b)=(7.2)/(48//c)` or 0.3 a=0.1, b=0.15c, or 3a=b=1.5c. thus, if b=1, then `a=(1)/(3)`,
`c=(1)/(1.5)=(2)/(3)`
`therefore`Ratio `a:b:c=(1)/(3):1:(2)/(3)=1:3:2`
4.

Same mass of CH_(4) and H_(2)is taken in container. The partial pressure caused by H_(2) is

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`8 //9`
`1//9`
`1//2`
1

Solution :`N_(CH_(4))=` NUMBER of MOLES of `CH_(4)=(m)/(16)`
`N_(H_(2))= ` number of moles of `H_(2) = (m)/(2)`
fractionpartial pressure of `H_(2)` is
`H_(2)=(n_(H_(2)))/(n_(H_(2))+n_(CH_(4)))=((m)/(2))/((m)/(2)+(m)/(16))=((m)/(2))/((9M)/(16))=(8)/(9)`
5.

Same quantity of electrical charge that deposited0.583 g of silver was passed through a solution of gold salt. If 0.335 g of gold is deposited, calculate the oxidation state of gold in the given salt. At wt of Au = 197.

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ANSWER :`+3`
6.

Same mass of CH_(4) and H_(2) is taken in container. The partial pressure caused by H_(2) is

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`(8)/(9)`
`(1)/(9)`
`(1)/(2)`
1

Answer :A
7.

Same amount of electricity is passed through solution of ferrous chloride and ferric chloride . Ratio of weight of iron deposited in the two solution is

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`1:1`
`1:2`
`2:3`
`3:2`

Solution :`UNDERSET("Ferrous")(FE^(++) + e^(-) to Fe) ""underset("Ferric")(Fe^(+3) + 3E^(-) to Fe)`
`2E^(-) xx 3 : 3e^(-) xx 2 therefore 3:2`
8.

Same amount of electric current is passed through solutions of AgNO_(3) and HCl. If 1.08g of silver is obtained in the first case, the amount of hydrogen liberated at S.T.P. in the second case is

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`224cm^(3)`
`1.008g`
`112cm^(3)`
`22400cm^(3)`

Solution :According to Faraday.s second law
`("Mass of Ag")/("Mass of H")=("EQUIVALENT mass of SILVER")/("Equivalent mass of hydrogen")`
or `(1.08)/("Mass of H")=(108)/(1)` or mass, `H=0.01g`
`because2.00` gm of `H_(2)` occupies 22400 ml at STP
`therefore 0.01`gm of `H_(2)` will OCCUPY`=(22400xx0.01)/(2)`
`=112cm^(3)`.
9.

Samarium shows the oxidation state

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`+3 and +4`
`+2,+3 and +4`
`+2,and+3`
only `+3`

ANSWER :C
10.

Same amount of electric current is passed through solutions of AgNO_3and HCl. If 1.08 g of silver is obtained in the first case, the volume of hydrogen liberated at S.T.P. in the second case is

Answer»

`112 cm^3`
`22400 cm^3`
`224 cm^3`
1.008g

ANSWER :A
11.

Salvarsan is arsenic containing drug which was first used for the treatment of.________.

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SYPHILIS
TYPHOID
Meningites
DYSENTRY

ANSWER :A
12.

Salvarsan is arsentic containing drug which was first usedfor the treatmentof "……."

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syphilis
typhoid
meningitis
dysentry

Solution :Syphills is an acute and chronic infections disease CAUSED by the bacterium treponaema pallidum, it is a sexually transmitted infection. The primary route of transmission is through sexual contact but it may also be transmitted frommother to foetus during pregnancy or at birth.
Paul EHRLICH investigated arsenic based structure in order to produce less toxic substances for the treatement of syphillis as he got Nobel PRIZE for medicine in `1908` for this discovery. Salvarsan was the firsteffective medicine discoveredfor syphilis. ALTHOUGH salversan is toxic to human beings its effect on bacteria is much greater than on human being. Strucutre of salvarsanis -
13.

Salvarsan is having similarity in structure as that of

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azodye
penicillin
OFLOXACIN
CHLORAMPHENICOL

ANSWER :A
14.

Salvarsanis arsenic containing drug which was firstused for the treatment of ___________

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SYPHILIS
typhoid
meningitis
dysentry

Solution : SALVARSAN, an arsenic containing compound, was FIRST USED for the treatment of syphilic (a S.T.D.).
15.

Salvarsan is arsenic containing drug which was first used the treatment of

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syphilis
TYPHOID
meningitis
dysentry

Solution : Salvarsan, an arsenic CONTAINING compound, was first used for the TREATMENT of syphilic (a S.T.D.).
16.

Salvarsan is arsenic containing drug which was first used for the treatment of ..

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SYPHILIS
typhoid 
meningitis
dysentry 

SOLUTION :syphilis
17.

Salvarsan is arsenic containing drug which was first used for the treatment of

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syphilis
typhoid
meningitis
dysentry

Answer :A
18.

Salvarsan is arsenic containing drug which was first used for the treatment of _____

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syphilis
typhoid
MENINGITIS
DYSENTRY

SOLUTION :SALVARSAN was the first effective TREATMENT discovered for syphilis.
19.

Salts of which of the following elements are mostly blue in colour?

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Cu
ZN
Fe
Cr

Solution :SALTS of Cu ELEMENT are mostly blue in colour .
20.

Salvarsan is arsenic containing drug which was first used for the treatment of ________

Answer»

syphilis
typhoid
meningitis
DYSENTRY

ANSWER :A
21.

Salts of sorbic acid and propionic acid are used as:

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ANTIOXIDANTS
flavouring AGENTS
food PRESERVATIVES
nutrional supplement

Answer :C
22.

Salts of metals X, Y and Z are electrolysed under identical condition using same quantity of electricity . Ifwas observed that 4.2 g of X, 5.4 g of Y and 19.2 g of Z were deposited at respetive cathode . Ifthe atomic weights of X , Y, Z are 7, 27 and 64 respectively , then their ratio of valencies is

Answer»

`1:2:3`
`1 : 3 : 2`
`2: 3 : 1`
`3: 2:2`

ANSWER :B
23.

Salts of sorbic acid and propionic acid are used as

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Antioxidants
Flavouring Agent
Food preservatives
Nutiritional SUPPLEMENTS 

ANSWER :C
24.

Salts can be obtained from a concentrated sea water by :

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Catalyst
Evaporation
Hydrolysis
Crystallisation

Answer :D
25.

Salt 'X' + excess NaOH solution overset("warm")rarr'Y' ("gas")+'Z' ("solution") 'Z'("solution")+BaCl_(2)rarr"white ppt" Which of the following salt follow above reaction.

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`NA(NH_(4))HPO_(4).4H_(2)O`
`K_(2)SO_(4).Cr_(2)(SO_(4))_(3)24H_(2)O`
`(NH_(4))_(2)Cr_(2)O_(7)`
`KCl.MgCl_(2).6H_(2)O`

Solution :`3^(@)` alcoholcannot be oxidised.
26.

Salts of A (atomic weight 7), B (atomic weight 27) and C (atomic weight 48) were electrolysed under identical condition using the same quantity of electricity. It was found that when 2.1 g of A was deposited, the eight of B and C deposited were 2.7 and 7.2 g. The valencies of A,B and C are respectively :

Answer»

`3,1 and 2`
`1,3 and 2`
`3,1 and 3`
`2,3 and 2`

ANSWER :B
27.

Salt with which one of the following anion produce deep blue colour with starch and Kl is

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CHLORIDE
NITRITE
acetate
bromide

ANSWER :B
28.

Salt used as a purgative is:

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NACL
`MgSO_4.7H_2O`
`Ca_3Al_2O_6`
`MgCl_2.6H_2O`

ANSWER :B
29.

Salt of the following is used as a water softner

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`H_(4)P_(2)O_(6)`
`H_(4)P_(2)O_(7)`
`HPO_(3)`
`HPO_(2)`

ANSWER :3
30.

Saltmixture overset(dil. HCI) to Saltis consistingof cation

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`Pb^(2+)` and `HG^(2+)`
`Pb^(2+)` and `Hg_(2)^(2+)`
`Pb^(2+)` and `Ag^(o+)`
`Pb^(2+), Hg_(2)^(2+)` and `Ag^(o+)`

ANSWER :C
31.

Salt cake is

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SODIUM SULPHATE
sodium chloride
Sodium bisulphide
Sodium sulphate and sodium chloride

Answer :A
32.

Salt bridge is used to

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CONNECT two half cells
maintain ELECTRICAL neutrally
reduced junction POTENTIAL
all

Solution :These are the FUNCTIONS of SALT bridge .
33.

Salt and water is formed by acid-base neutralisation reaction. If ratio of moles of acid & base taken is not similar to the ratio of their stoichiometric coefficient, then one of the component is limiting reagent.Assume no dissociation of water in following reactions. (Base is 80% pure only, take impurity present as inert & non electrolytic ) Select the correct combination for the resulting acidic solution.

Answer»

<P>(I)(ii)(S)
(I)(iv)(S)
(I)(ii)(P)
(II)(i)(R)

SOLUTION :(i)Mass of pure NaOH`=(10xx80)/100=8 gm`
`{:(NaOH+,HCl to ,NaCl,+H_2O),(8/40=0.2 "mole",(8xx500)/1000,-,-):}`
=0.4 mole
`=0.2 "mole" " " 0.2"mole"`
BASE in L.R.,`[H^+]=0.2 M " " [Na^+]=0.2 M [Cl^(-)]=0.4 M`
(ii)KOH pure `=(28xx80)/100=22.4 gm`
`{:(KOH+,HNO_3to,KNO_3,+H_2O),(22.4/56=0.4 "mole",(2.5xx500)/1000,-,-):}`
=0.1 mole
`=0.3 "mole" " " 0.1"mole"`
Acid in L.R.,`[OH^(-)]=0.3 M " " [K]=0.4 M [NO_3^(-)]=0.1 M`
(iii) `{:(Ca(OH)_2+,H_2SO_4to,CaSO_4,+2H_2O["Pure" Ca(OH)_2=37xx0.8=29.6 gm]),(29.6/74=0.4 ,(0.8xx500)/1000=0.4,-,-):}`
`[Ca^(2+)]=[SO_4^(2-)]=0.4M`
(iv) `{:(Ba(OH)_2+,2HBrto,BaBr_2,+2H_2O["Pure" Ba(OH)_2=342xx0.8=,273.6 gm]),(273.6/171=1.6 ,(6.4xx500)/1000=3.2,-,-),(-,-, ,1.6 "mole"):}`
`[Ba^(2+)]=1.6 M " " [Br^(-)]=3.2M`
34.

Salt and water is formed by acid-base neutralisation reaction. If ratio of moles of acid & base taken is not similar to the ratio of their stoichiometric coefficient, then one of the component is limiting reagent.Assume no dissociation of water in following reactions. (Base is 80% pure only, take impurity present as inert & non electrolytic ) Select incorrect combination

Answer»

(I)(II)(P)<BR>(II)(i)(R)
(IV)(iv)(R)
(III)(ii)(S)

Solution :(i)Mass of pure NaOH`=(10xx80)/100=8 gm`
`{:(NaOH+,HCl to ,NaCl,+H_2O),(8/40=0.2 "mole",(8xx500)/1000,-,-):}`
=0.4 mole
`=0.2 "mole" " " 0.2"mole"`
Base in L.R.,`[H^+]=0.2 M " " [Na^+]=0.2 M [Cl^(-)]=0.4 M`
(ii)KOH pure `=(28xx80)/100=22.4 gm`
`{:(KOH+,HNO_3to,KNO_3,+H_2O),(22.4/56=0.4 "mole",(2.5xx500)/1000,-,-):}`
=0.1 mole
`=0.3 "mole" " " 0.1"mole"`
Acid in L.R.,`[OH^(-)]=0.3 M " " [K]=0.4 M [NO_3^(-)]=0.1 M`
(iii) `{:(Ca(OH)_2+,H_2SO_4to,CaSO_4,+2H_2O["Pure" Ca(OH)_2=37xx0.8=29.6 gm]),(29.6/74=0.4 ,(0.8xx500)/1000=0.4,-,-):}`
`[Ca^(2+)]=[SO_4^(2-)]=0.4M`
(iv) `{:(Ba(OH)_2+,2HBrto,BaBr_2,+2H_2O["Pure" Ba(OH)_2=342xx0.8=,273.6 gm]),(273.6/171=1.6 ,(6.4xx500)/1000=3.2,-,-),(-,-, ,1.6 "mole"):}`
`[Ba^(2+)]=1.6 M " " [Br^(-)]=3.2M`
35.

Salt and water is formed by acid-base neutralisation reaction. If ratio of moles of acid & base taken is not similar to the ratio of their stoichiometric coefficient, then one of the component is limiting reagent.Assume no dissociation of water in following reactions. (Base is 80% pure only, take impurity present as inert & non electrolytic ) Select the correct combination for the resulting basic solution.

Answer»

(I)(iii)(S)
(I)(iv)(R)
(II)(i)(Q)
(III)(ii)(S)

SOLUTION :(i)Mass of pure NaOH`=(10xx80)/100=8 gm`
`{:(NaOH+,HCL to ,NaCl,+H_2O),(8/40=0.2 "mole",(8xx500)/1000,-,-):}`
=0.4 mole
`=0.2 "mole" " " 0.2"mole"`
Base in L.R.,`[H^+]=0.2 M " " [Na^+]=0.2 M [CL^(-)]=0.4 M`
(ii)KOH pure `=(28xx80)/100=22.4 gm`
`{:(KOH+,HNO_3to,KNO_3,+H_2O),(22.4/56=0.4 "mole",(2.5xx500)/1000,-,-):}`
=0.1 mole
`=0.3 "mole" " " 0.1"mole"`
Acid in L.R.,`[OH^(-)]=0.3 M " " [K]=0.4 M [NO_3^(-)]=0.1 M`
(iii) `{:(Ca(OH)_2+,H_2SO_4to,CaSO_4,+2H_2O["Pure" Ca(OH)_2=37xx0.8=29.6 gm]),(29.6/74=0.4 ,(0.8xx500)/1000=0.4,-,-):}`
`[Ca^(2+)]=[SO_4^(2-)]=0.4M`
(iv) `{:(BA(OH)_2+,2HBrto,BaBr_2,+2H_2O["Pure" Ba(OH)_2=342xx0.8=,273.6 gm]),(273.6/171=1.6 ,(6.4xx500)/1000=3.2,-,-),(-,-, ,1.6 "mole"):}`
`[Ba^(2+)]=1.6 M " " [Br^(-)]=3.2M`
36.

Salt bridge is used because it

Answer»

maintains the electrical neutrality of the TWO half cells
It enhances the FLOW of electrons by OVERCOMING liquid jnction potential
It provides the lost ions
It forms insoluble precipitates with the electrolytes in the two half cells

Solution :FUNCTION of salt bridge.
37.

Salt A overset("Layer test") to If reddish brownlayer come first , then

Answer»

`BR^(Θ)` PRESENT
`Br^(Θ)` absent
`CI^(Θ)` present
`I^(Θ)` present

Solution :`2Br^(Theta) overset(CI_(2))underset(water) to Br_(2)`: `C CI`layer BECOMES red or reddish brown
`I^(Theta)`ion is oxidised preferably COMPOUND to `Br^(Theta)`,Hence
`I^(Theta)` ID absent

38.

Salt (A) makes part of electrode and is insoluble in water (A) is blackened by NH_(3) forming (B),(B) is soluble is equa regia forming (C ),(C ) gives orange ppt with KI but ppt dissolves in extcess of KIforming (D ) , identify (A),(B),(C ) and (D)

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Solution :(A) `Hg_(2)CI_(2)` (CALOMEL) (B ) `(HgNH_(2)CI+ Hg)`
(C ) `HgCI_(2)`(D) `H_(2)HgI_(4)`
39.

Salt (A) is a white deliquescent solid. On heating the solid, brown fumes were evolved. On adding NaOH to the salt solution of (A), a white gelatinous ppt. was obtained. On adding, a drop of blue litmus solution to the ppt., a blue lake was obtained. On adding DPA to the salt solution, a deep blue colouration was obtained. Identify the salt and give the equations involved.

Answer»

Solution :(i) `2AL(NO_(3))_(3)OVERSET(Delta)toAl_(2)O_(3)+6NO_(2)uarr+(3)/(2)O_(2)uarr`
`(ii) `Al(NO_(3))_(3)+3NaOHtoAl(OH)_(3)darr+3NaNO_(3)`
`Al(OH)_(3)+"Blue litmus solution" to"Blue lake"`
[Note: A lake is a ppt. floating in a clear liquid.]
(iii) `NO_(3)^(-)+(C_(6)H_(5))_(2)NHtoNO_(2)^(-)+(C_(6)H_(3))_(2)N-N(C_(6)H_(5))_(2)+H_(2)O`
40.

Salol (phenyl salicylate) is used as an :

Answer»

Insecticide
Analgesic
Ointment
Intestinal antiseptic

Answer :D
41.

Salol can be used as:

Answer»

ANTISEPTIC
ANTIPYRETIC
both
none.

Answer :A
42.

Salol can be used as :

Answer»

ANTISEPTIC
ANTIPYRETIC
Analgesic
None of these

Answer :A
43.

Saliva contains:

Answer»

Amylases
Bile
Vitamins
Trypsin

Answer :A
44.

Saline soil contains :

Answer»

HIGH CONCENTRATION of salt
Lot of moisture
Hard rocks
None of the above

Answer :A
45.

Salicylic acid on brornination gives:

Answer»

2,4,6-tribromosalicylic ACID
2,4,6-tribromophenol
2,4,6-tribromobenzoic acid
p-bromosalicylic acid

ANSWER :B
46.

Saline hydrides are :

Answer»

STRONG oxidants
Strong reductants
Strong dehydrading agents
Strong BLEACHING agents

Answer :B
47.

Salicylic acid on heating with sodalime forms:

Answer»

PHENOL
Benzene
Benzyl alcohol
Benzoic acid

Answer :A
48.

Salicylic acid on heating with soda lime (CaO+NaOH) gives :

Answer»

Benzene
Benzoic acid
Phenol
Toluene.

Solution :
49.

Salicylic acid is produced when phenol in alcoholic KOH is treated with

Answer»

`CH_(3)CL`
`CHCl_(3)`
`CH_(2)Cl_(2)`
`"CCL"_(4)`

Answer :D
50.

Salicylic acid is used to get

Answer»

OIL of WINTER GREEN
Salol
Aspirin
Anisole.

Answer :A::B::C