94420 + Interview Questions in Chemistry in Class 12

1.	An antibiotic contains nitro group attached to aromatic nucleus. It is
Answer» Tetracycline Streptomycin Penicillin CHLORAMPHENICOL Solution :Chloramphenicol is

Discussion

2.	An antibiotic with a broad spectrum
Answer» KILLS the antibodies Acts on a specific antigen Acts on DIFFERENT antigens Acts on both the antigens and antibodies Solution :Broad SPECTRUM antibiotics act on different antigens.

Discussion

3.	An antibiotic contains nitro group attached to aromatic nucleus . It is :
Answer» Penicillin Streptomycin Tetracycline Chloramphencol Answer :D

Discussion

4.	…………………..an anti cancer agent used to treat stomach and colon cancer.
Answer» ANSWER :MITOMYCIN C

Discussion

5.	An anti-freeze solution is prepared from 222.6 g of ethylene glycol C_(2) H_(4) (OH)_(2) and 200 g of water . Calculate themolality of the solution. If the density of this solution be 1.072 g mL^(-1) , what will be the molarity of the solution ?
Answer» Solution :Mg of `C_(2) H_(4) (OH)_(2) = 62 g mol^(-1)` Molality = `(n_(B))/(W_(A))xx 1000 = (W_(B))/(M_(B) xx W_(B)) xx 1000 = (222.6 xx 1000)/(62 xx 200) = 17.95 m ` DENSITY= `("Mass")/("Volume")` So , Volume = `("Mass")/("Density") = (422.6)/(1.072) = 394.22` ml `M = (n_(B))/(V) xx 1000` `= (222.6)/(394.22 xx 62) xx 1000 = 9.11` M

Discussion

6.	An antibiotic contains nitro group attached to aromatic nucleus in its structure. It is
Answer» PENCILLIN sulphadiazine tetracycline CHLORAMPHENICOL ANSWER :D

Discussion

7.	An analytical balance has uncertainity in measurement equal to pm1 mg. Then the result in terms of persentage would be if the weight of a compound is 10 g
Answer» `10pm0.1%` `10pm0.01%` `10pm1%` `10pm0.001%` ANSWER :B

Discussion

8.	An anhybride and an ester can be distinguished with
Answer» `C_2H_5OH` `NH_3` water aqueous NaOH Answer :C

Discussion

9.	An aniline on nitration gives
Answer» Both a and C ANSWER :D

Discussion

10.	An analyst starts a first order chemica reaction at 8.00 A.M. in the morning at the laboratory temperature of 27^(@) C At 1.00 P.M. he discovered that only 10% of the reaction was complete by that time To speed-up the reaction he increased the temperature to 127^(@) C At 4.00 P.M. he found that only 50% of the reaction was complete Any how he did not want to stay in laboratory beyond 5.00 P.M. but he could not leave the laboratory until the reaction was 90% complete Fortunately he found a suitable catayst adding which at 4.00 P.M. at 127^(@) C he could meet the target of 5.00 P.M. and 90% Answer the following questions based on theabove observation (Use l n 10/9 = 0.1 l n 9/5=0.6, l n10=2.3 l n5=1.6,l n8=2) What was the activation energy of the catalyzed pathway?
Answer» `4.92 kcal//mol` `3.92 kcal//mol` `4.72 K cal//mol` `9.84 kcal//mol` ANSWER :B

Discussion

11.	An analysis of the hydrolysis products of salmine, a polypeptide from salmon gave following result of weights of amino acidsd in gram per 109.66g of salmine{:(Ie :,"Isoleusine : 1.31","Alanine : 0.89","Serine : 7.35","Argemine : 86.40"),(,"valine : 3.51","Glycine : 3.0","Proline : 6.90",):} {:("molecular weight of salmine is : 10, 966","molecular weight of Serine : 105"),("molecular weight of alanine is : 89","molecular weight of Argenine : 174"),("molecular weight of Isoleucine : 131","molecular weight of Protine : 115"),("molecular weight of Valine : 117","molecular weight of Glycine : 75"):}Salmine is also known as
Answer» `Ala. Arg_(50).Gly_(4).Ile Pro_(6). Ser_(7)Val_(3)` `Ala. Arg_(50).Gly_(14).Ile_(3).Pro_(6).SER.Val` `Ala.Arg_(50).Gly_(3).Ile_(4).Pro_(6).Ser_(7).Val` `Ala.Arg_(50).Gly_(6).Ile.Pro_(4).Ser_(7).Val_(3)` Solution :Salmine composition is `Ala, Arg_(5)-Gly_(4)-Ile-Pro_(6)-Ser_(7)-Val_(3)`

Discussion

12.	An analyst starts a first order chemica reaction at 8.00 A.M. in the morning at the laboratory temperature of 27^(@) C At 1.00 P.M. he discovered that only 10% of the reaction was complete by that time To speed-up the reaction he increased the temperature to 127^(@) C At 4.00 P.M. he found that only 50% of the reaction was complete Any how he did not want to stay in laboratory beyond 5.00 P.M. but he could not leave the laboratory until the reaction was 90% complete Fortunately he found a suitable catayst adding which at 4.00 P.M. at 127^(@) C he could meet the target of 5.00 P.M. and 90% Answer the following questions based on theabove observation (Use l n 10/9 = 0.1 l n 9/5=0.6, l n10=2.3 l n5=1.6,l n8=2) What was the activation energy of the original pathway?
Answer» `10.14 kcal//mol` `5.52 kcal//mol` `2.64 kcal//mol` `7.92 kcal//mol` ANSWER :B

Discussion

13.	An analgesic is used to
Answer» KILL bacteria arrest growth relieve pain alll of these ANSWER :C

Discussion

14.	An analysis of pyrex glass showed 12.9%B_(2)O_(3),2,2% Al_(2)O_(3).3.8% Na_(2)O,0.4% K_(2)O and remaining is SiO_(2). What is the ratio of silicon to boron atoms in the glass?
Answer» Solution :PERCENTAGE composition of `B_(2)O_(3)=12.9%` Percentage composition of `SiO_(2)=100-[12.9+2.2+3.8+0.4]` =80.7% Number of moles of `B_(2)O_(3)=("MASS")/("Molar mass")=(12.9)/(70)=0.184` Number of moles of boron atoms `=2xx0.184` Number of moles of `SiO_(2)=("Mass")/("Molar mass")=(80.7)/(60)=1.345` Number of moles of silicon atoms =1.345 `("Number of atoms of silicon")/("Number of atoms of boron")=(N_(A)xx1.345)/(N_(A)xx0.184)=(7.3)/(1)` Where `N_(A)=` AVOGADRO's number.

Discussion

15.	Choose the most appropriate answer from the following options : Identify the metallic oxide which is amphoteric in nature : Calcium oxide Barium oxide Zinc oxide Copper(ll)oxide
Answer» `NA2O` `SO_2` `B_2O_3` ZnO Answer :D

Discussion

16.	An amphoteric oxide out of the following is :
Answer» `NA2O` `SO_2` `B_2O_3` ZnO Answer :D

Discussion

17.	An amount of solid NH_(4)HSis placed in a flask already containing ammonia gas at a certain temperature and 1.0 atm pressure. Ammonium hydrogen sulphide decomposes to yield NH_(3)and H_(2)Sgases in the flask. When the decomposition reaction reaches equilibrium, the total pressure in the flask rises to 2 atm. What will be the equilibrium constant for NH_4HS decomposition at this temperature?
Answer» <P> SOLUTION :`underset("initial At. EQN")(NH_(4)HS(s)) X atm)(H_(2)S)(g)` Then, `1.0 + x + x=2x+1.0=2.0` (given) `rArr x=0.5` atm `P_(NH-(3)) =1.0 + 1.5 1.5 atm, p-(H_(2)S) = 0.5 atm^(2)` `0.75 atm^(2)`

Discussion

18.	An amount of solid NGH_(4)HS is placed ina flask already containg ammonia gas at a certain temperaturee and 0.50 atm. Pressue. Ammounium hydrogen sulphide decomposes to yield H_(3)and H_(2)S gases in the flask. When the decomposition reaction reaches equlibrium, the total pressure in the flask rises to 0.84 atm. The equilibrium constant for NH_(4)HS decompositions at this temperaturee is
Answer» `0.30` `0.18` `0.17` `1.11` SOLUTION :`{:(NH_(4)HShArrNH_(3(g))+H_(2)S_((g))),("""a""0.5atm"),(""a-X ""0.5+x ""x):}` Total PRESSURE `=0.5+2x=0.84 i.e., x=0.17` `K_(p)=P_(NH_(3)).P_(H_(2)S)=(0.67).(0.17)=0.1139`

Discussion

19.	An amorphous solid (X) burns in air to form a gas ( Y) which turns lime water milky. This gas decolourises aqueous solution of acidified KMnO_(4). Gas (Y) reacts with oxygen to give another gas (Z) which is responsible for acid rain. X, Y and Z are
Answer» X-C, Y-CO, Z-`CO_2` X-S, Y-`SO_2` , Z-`SO_3` X-P , Y-`P_2O_3` ,Z - `P_2O_5` X-S , Y-`SO_3` ,Z-`H_2SO_4` Solution :`{:(S,+O_2,toSO_2),("(X)",,"(Y)"):}` `{:(SO_2+,Ca(OH)_2to , CaSO_3 darr , + H_2O),("(Y)",,"white ppt.",):}` `{:(2KMnO_4+,5SO_2+,2H_2OtoK_2SO_4+,2MnSO_4 +,2H_2SO_4),("Purple","(Y)",,"colourless",):}` `{:(2SO_2+,O_2to,2SO_3),("(Y)",,"(Z)"):}` `underset"(Z)"(SO_3) + H_2O to H_2SO_4` (responsible for ACID RAIN )

Discussion

20.	An amorphous solid 'A' which has a crown shaped structure, burns in air to form a gas 'B' which turns lime water milky. 'B' is also produced by roasting of sulphide ores. 'B' undergoes oxidation in the presence of V_(2)O_(5) to give 'C' and to carry out this oxidation low temperature and high pressure is mandatory to get a good yeild of 'C'. 'C' is then absorbed in H_(2)SO_(4) to give 'D'. 'D' is then diluted to give a very important. 'E' in concentrated form, when combined with Cu metal, gives compound 'F'. From this description Give two important functions of 'E' in the chemical industry.
Answer» SOLUTION :(i) MANUFACTURE of FERTILISERS LIKE ammonium sulphate. (ii) In detergent inductry.

Discussion

21.	An amorphous solid 'A' which has a crown shaped structure, burns in air to form a gas 'B' which turns lime water milky. 'B' is also produced by roasting of sulphide ores. 'B' undergoes oxidation in the presence of V_(2)O_(5) to give 'C' and to carry out this oxidation low temperature and high pressure is mandatory to get a good yeild of 'C'. 'C' is then absorbed in H_(2)SO_(4) to give 'D'. 'D' is then diluted to give a very important. 'E' in concentrated form, when combined with Cu metal, gives compound 'F'. From this description Give a balanced chemical equation for the conversion of 'E' to 'F'.
Answer» SOLUTION :`Cu+2H_(2)SO("CONC.")toCuSO_(4)+SO_(2)+2H_(2)O`

Discussion

22.	An amorphous solid 'A' which has a crown shaped structure, burns in air to form a gas 'B' which turns lime water milky. 'B' is also produced by roasting of sulphide ores. 'B' undergoes oxidation in the presence of V_(2)O_(5) to give 'C' and to carry out this oxidation low temperature and high pressure is mandatory to get a good yeild of 'C'. 'C' is then absorbed in H_(2)SO_(4) to give 'D'. 'D' is then diluted to give a very important. 'E' in concentrated form, when combined with Cu metal, gives compound 'F'. From this description Elucidate the structure of 'A' to 'F'.
Answer» SOLUTION :

Discussion

23.	An amorphous solid "A" burns in air to form a gas "B" which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aqueous KMnO_4 solution and reduces Fe^(3+) to Fe^(2+)Identify the solid "A" and the gas "B" and write the reactions involved.
Answer» Solution :(A) `S_(8)`, (B) `SO_(2)` with OXYGEN (air), `S_(8)` oxidises to `SO_(2)` `S_(8) + 8O_(2) overset(Delta)to 8SO_(2)` `SO_(2) + Ca(OH)_(2) to CaSO_(3) + H_(2)O` `5SO_(2) + underset("violet")(2MnO_(4)^(-)) + 2H_(2)O to 5SO_(4)^(2-) + 4H^(+) + underset("COLOURLESS") (2MN^(2+))` `2Fe^(3+) + SO_(2) + 2H_(2)O to underset("green")(2Fe^(2+)) + SO_(4)^(2-) + 4H^(+)`

Discussion

24.	An amorphous solid "A" burns in air to form a gas "B" which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aqueous KMnO_4 solution and reduces Fe^(3+) to Fe^(2+). Identify the solid "A" and the gas "B" and write the reactions involved.
Answer» Solution :The solid A is sulphur , `S_8` and the gas B is `SO_2`. The reactions are given as under : `S_8 + 8O_2 OVERSET(Delta)to 8SO_2` `2MnO_4^(-) + 5SO_2 + 2H_2O to 5SO_4^(2-) + 4H^(+) + underset("(Colourless)")(2MN^(2+))` `2Fe^(3+) + SO_2 + 2H_2O to 2Fe^(2+) + SO_4^(2-) + 4H^(+)` `SO_2` is produced as a by - product during roasting of sulphide ore. The sulphides are converted into oxideswith the EVOLUTION of `SO_2`.

Discussion

25.	An amorphous solid (A) burns in air to form a gas (B) which turns lime water milky . The gas is also produced as a byproductduring roasting of sulphide ore. This gas decolourises acidifiedaqueousKMnO_(4) solution and reduces Fe^(3+) to Fe^(2+). Identify the solid 'A' and the gas 'B' and write the reactions involved.
Answer» SOLUTION :(i) Since the byproduct of roasting to sulphide ore is `SO_(2)`. It turns lime water milky. Therefore, gas 'B'must be `SO_(2)`. (ii) As the gas 'B' is obtained when amorphous solid 'A' burns in air therefore, amorphous solid 'A' must be sulphur `s_(8)`. `underset("(A)")(S_(8))+8O_(2) overset(Delta)RARR underset("(B)")(8SO_(2))` Gas (B) reduces acidified aqueous KMnO4 solution and reduces `Fe^(3+)` to `Fe^(2+)` salts as shown below: `underset("(yellow)")(2MnO_(4)^(-))+underset("(B)")(SO_(2))+2H_(2)O rarr underset("(GREEN)")(2Fe^(2+)+SO_(4)^(2-)+4H^(+))` (IV) Thus, solid 'A' is `S_(8)` and gas 'B' is `SO_(2)`.

Discussion

26.	An amorphous solidA burnsin airto form a gas B whichturns limewatermilky. Thegasis also producedduringroasting of sulphide ore. This gasdecolourises acidifedaqueousKMnO_(4) solutionand reduces Fe^(3+) to Fe^(2+). Identify the solid 'A' and thegas B and write thereactionsinvolved .
Answer» Solution :`A to S_(8) , B to SO_(2) , S_(8) + 8O_(2) OVERSET(Delta)to 8SO_(2)` `underset("(VIOLET)")(2MnO_(4)^(-)) + 5SO_(2) + 2H_(2)O to5SO_(4)^(2-) +4H^(+) + underset("(colouless)")(2Mn^(2+))` `2Fe^(3+) + SO_(2) + 2H_(2)Oto 2Fe^(2+) + SO_(4)^(2-) + 4H^(+)`

Discussion

27.	An amorphous solid 'A' burns in air to form a gas 'B' which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aqueous KMnO_(4) solution and reduces Fe^(3+) to Fe^(2+). Identify the solid "A" and the gas "B" and write the reaction involved.
Answer» Solution :(i) Since gas 'B' is obtained as a by-product during roasting of sulphide, therefore, gas 'B' must be `SO_(2)`. `2 ZnS + 3 O_(2) rarr 2 ZnO + 2 SO_(2) (B)` (ii) Since gas 'B' is obtained when AMORPHOUS SOLID 'A' burns in air, therefore, amorphous solid 'A' must be SULPHUR, `S_(8)` `S_(8) (A) + 8 O_(2) rarr 8 SO_(2) (B)` (iii) Gas 'B' reduces ACIDIFIED `KMnO_(4)` solution and reduces `Fe^(3+)` to `Fe^(2+)` salts as shown below : `{:(underset(("Purple"))(2MnO_(4)^(-)) + underset((B))(5SO_(2))+ 2H_(2)O rarr underset(("COLOURLESS"))(2Mn^(2+))+5SO_(4)^(2-) + 4H^(+)),(underset(("Yellow"))(2Fe^(3+))+underset((B))(SO_(2))+2H_(2)O rarr underset(("Green"))(2Fe6(2+)) + SO_(4)^(2-) + 4 H^(+)):}` Thus, solid 'A' = `S_(8)` and gas 'B' = `SO_(2)`.

Discussion

28.	An amorphous solid ‘A’ burns in air to form a gas ‘B’ which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aq. KMnO_(4) solution. Identify the solid ‘A’ and the gas ‘B’ and write the reaction involved. Write its any two uses.
Answer» SOLUTION :It is USED as BLEACHING AGENT and DISINFECTANT.

Discussion

29.	An amorphous solid ‘A’ burns in air to form a gas ‘B’ which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aq. KMnO_(4) solution. Identify the solid ‘A’ and the gas ‘B’ and write the reaction involved. What happens when SO_(2) is passed through water and reacts withNaOH ? Write balanced equation.
Answer» Solution :`2NaOH+SO_(2)(G)rarrNa_(2)SO_(3)(aq)+H_(2)O` `Na_(2)SO_(3)(aq)+SO_(2)+H_(2)Orarr2NaHSO_(3)(aq)`

Discussion

30.	An amorphous solid ‘A’ burns in air to form a gas ‘B’ which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aq. KMnO_(4) solution. Identify the solid ‘A’ and the gas ‘B’ and write the reaction involved. How is SO_(2) prepared in laboratory ?
Answer» Solution :`Na_(2)SO_(3)(s)+H_(2)SO_(4)(aq)rarrSO_(2)(g)+Na_(2)SO_(4)(aq)+H_(2)O(L)`

Discussion

31.	An amorphous solid ‘A’ burns in air to form a gas ‘B’ which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aq. KMnO_(4) solution. Identify the solid ‘A’ and the gas ‘B’ and write the reaction involved.
Answer» SOLUTION :`A = S_(8), B = SO_(2) (G)`

Discussion

32.	An ammonia solution is 9.9% ammonia by mass and has a density of 0.99 g/mL. Calculate the pH of the solution. K_b (NH_4OH) = 1.7 xx 10^(-5)
Answer» ANSWER :`12.0`

Discussion

33.	An amino acid with a phenolic hydroxyl group is
Answer» alanine tyrosine valine phenyl glycine Answer :B

Discussion

34.	An amine (X) reacts with benzene sulphonyl chloride and the product thus obtained is soluble in KOH . The amine (X) is
Answer» `1^(@)`amine `2^(@)` amine `3^(@)` amine NONE of thesen Solution :Since an ainine (X) REACTS with benzene sulphonyl CHLORIDE to form a product which is soluble in KOH, therefore, amine (X) must be a `1^(@)` amine.

Discussion

35.	An amine reacts with CH_(3)SO_(2)Cl and the product is soluble in alkali, amine is
Answer» `1^(@)` AMINE `2^(@)` amine `3^(@)` amine All of these Answer :1

Discussion

36.	An amino acid is characterized by two pKa values the one correspondingto the more acidic site is designated as pKa_1 and the other corresponding to the less acidic site is designated as pKa_2 The isoelectric point also called isoionic point (pI) is the pH at which concentration of zwitter ion is maximum . pI is the average of pKa_1 and pKa_2.Generally the value of pI is slightly less than 7. some amino acids have side chain with acidic or basic groups.These amino acids have pKa_3 value also for the side chain.Acidic amino acid have acidic side chains and basic amino acids have basic side chains . pI for acidic amino acid is average of pKa_1 and pKa_3.pI for basic amino acid is the average of pKa_2 and pKa_3. {:(S.NO,"Amino acid",p^(Ka1),p^(Ka2),p^(Ka3)("side chain")),(I,"Aspartic acid",1.88,9.6,3.65),(II,"Glutamic acid",2.19,9.67,4.25),(III,"Lysine",2.18,8.95,10.53),(IV,"Arginine",2.17,9.04,12.48):} In the table given above the acidic amino acids are
Answer» I,II I,III II,III I,II, IV Solution :`P_3^(KA)` value of side chain DETERMINES the NATURE of amino acid

Discussion

37.	An amine reacts with C_6H_5SO_2Cl and the productis soluble in alkali amine is
Answer» `3^(@)` `1^(@)` `2^(@)` All ANSWER :B

Discussion

38.	An amine reacts with C_6H_5SO_2Cl and the product is soluble in alkali, amine is :
Answer» `1^@` `2^@` `3^@` All Answer :A

Discussion

39.	An amine reacts with benzenesulphonyl chloride to form a white precipitate which is insoluble in aq. NaOH. The amine is
Answer» SOLUTION :`2^(@)` amines REACT with benzenesulphonyl chloride to give the corresponding benzenesulphonamide which due to the absence of acidic H on N does not dissolve in aq. NaOH.

Discussion

40.	An amine hormone is
Answer» Cortisone ADRENALINE Insulin Estrone Solution :Adrenaline is AMINE HORMONE.

Discussion

41.	An amine A reacts with benzene sulphonyl chloride and the product, thus, formed is soluble in KOH. The correct representation of the functional group of amine is
Answer» `-NH` `-NH_(2)` `-underset(\|)overset(\|)(N)-` both A and B. Solution :Only a `1^(@)` amines (with `-NH_(2)` group) REACT with benzene sulphonyl CHLORIDE to give a product which is soluble in `KOH`. On the other HAND `2^(@)` amines react with benzene sulphonyl chloride to give a product which is insoluble in `KOH` whereas `3^(@)` amines do not react with benzene sulphonyl chloride.

Discussion

42.	An amine C_(3)H_(9)N reacts with benzene sulphonyl chloride to fonn a white precipitate which is insoluble in aq. NaOH. The amine is
Answer» Solution :`2^(@)`amine reacts with benzene sulphonyl CHLORIDE and the product FORMED is insoluble in NaOH. Therefore, the amine should have only ONE H-atom attached to nitrogen atom.

Discussion

43.	An ambident nycleophile is
Answer» AMMONIA Ammonium ion Chloride ion NITRITE ion SOLUTION :Nitrite ion

Discussion

44.	An alumina-silica clay called bentonite is dropped from aeroplanes in the slurry form for :
Answer» FERTILIZING the soil Spreading WATER over fires Cooling the soil Fumigation Answer :D

Discussion

45.	An alpha- paticle approaches the target nucleus of copper (Z = 29) is such a way that the vlaue of impact parameter is zero. The distance of closest approach will be
Answer» `(2pi epsilon_(0)(K.E.)_(alpha))/(29e^(2))` `(29e^(2))/(2pi epsilon_(0)(K.E.)_(alpha))` `(4pi epsilon_(0)(K.E.)_(alpha))/(29e^(2))` `(K.E.)_(alpha)` ANSWER :B

Discussion

46.	An alpha-helix is a structural feature of
Answer» Sucrose. Polypeptides. Nucleotides. Starch. Answer :B

Discussion

47.	An alpha-amino acid exists as, overset(+)(NH_3)-underset(R)underset(\|)CH-COOH at (pH=2) and its isoelectric point is 6. The amino acid at pH 10.97 will exist as :
Answer» `OVERSET(+)(NH_3)-UNDERSET(R)underset(\|)CH-COO^-` `NH_2-underset(R)underset(\|)CH-COO^-` `NH_2-underset(R)underset(\|)CH-COOH` `underset(+)(NH_2)-underset(R)underset(\|)overset(-)CH-COOH` ANSWER :B

Discussion

48.	An alloy which does not contain copper is :
Answer» Solder Bronze Anode mud Electrolyte Answer :A

Discussion

49.	Which of the following alloys does not contain copper?
Answer» SOLDER Bronze Brass Bell METAL ANSWER :A

Discussion

50.	An alloy weighing 1.05g of Pb-Ag was dissolved in desired amount of HNO_(3) and the volume was made 350 mL. An Ag electrode was dipped in solution and E_(cell) of the cell underset(1 atm)(Pt H_(2)\|)underset(1 M)(H^(+))"\|\|"Ag^(+)\|Ag was 0.503V at 298K. calculate the percentage of lead in alloy. ("given," E_(Ag^(+)//Ag)^(@)=080V)
Answer» ANSWER :`99.967% ;`

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

An antibiotic contains nitro group attached to aromatic nucleus. It is

An antibiotic with a broad spectrum

An antibiotic contains nitro group attached to aromatic nucleus . It is :

…………………..an anti cancer agent used to treat stomach and colon cancer.

An anti-freeze solution is prepared from 222.6 g of ethylene glycol C_(2) H_(4) (OH)_(2) and 200 g of water . Calculate themolality of the solution. If the density of this solution be 1.072 g mL^(-1) , what will be the molarity of the solution ?

An antibiotic contains nitro group attached to aromatic nucleus in its structure. It is

An analytical balance has uncertainity in measurement equal to pm1 mg. Then the result in terms of persentage would be if the weight of a compound is 10 g

An anhybride and an ester can be distinguished with

An aniline on nitration gives

An analgesic is used to

An analysis of pyrex glass showed 12.9%B_(2)O_(3),2,2% Al_(2)O_(3).3.8% Na_(2)O,0.4% K_(2)O and remaining is SiO_(2). What is the ratio of silicon to boron atoms in the glass?

Choose the most appropriate answer from the following options : Identify the metallic oxide which is amphoteric in nature : Calcium oxide Barium oxide Zinc oxide Copper(ll)oxide

An amphoteric oxide out of the following is :

An amorphous solid (X) burns in air to form a gas ( Y) which turns lime water milky. This gas decolourises aqueous solution of acidified KMnO_(4). Gas (Y) reacts with oxygen to give another gas (Z) which is responsible for acid rain. X, Y and Z are

An amorphous solidA burnsin airto form a gas B whichturns limewatermilky. Thegasis also producedduringroasting of sulphide ore. This gasdecolourises acidifedaqueousKMnO_(4) solutionand reduces Fe^(3+) to Fe^(2+). Identify the solid 'A' and thegas B and write thereactionsinvolved .

An amorphous solid ‘A’ burns in air to form a gas ‘B’ which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aq. KMnO_(4) solution. Identify the solid ‘A’ and the gas ‘B’ and write the reaction involved.

An ammonia solution is 9.9% ammonia by mass and has a density of 0.99 g/mL. Calculate the pH of the solution. K_b (NH_4OH) = 1.7 xx 10^(-5)

An amino acid with a phenolic hydroxyl group is

An amine (X) reacts with benzene sulphonyl chloride and the product thus obtained is soluble in KOH . The amine (X) is

An amine reacts with CH_(3)SO_(2)Cl and the product is soluble in alkali, amine is

An amine reacts with C_6H_5SO_2Cl and the productis soluble in alkali amine is

An amine reacts with C_6H_5SO_2Cl and the product is soluble in alkali, amine is :

An amine reacts with benzenesulphonyl chloride to form a white precipitate which is insoluble in aq. NaOH. The amine is

An amine hormone is

An amine A reacts with benzene sulphonyl chloride and the product, thus, formed is soluble in KOH. The correct representation of the functional group of amine is

An amine C_(3)H_(9)N reacts with benzene sulphonyl chloride to fonn a white precipitate which is insoluble in aq. NaOH. The amine is

An ambident nycleophile is

An alumina-silica clay called bentonite is dropped from aeroplanes in the slurry form for :

An alpha- paticle approaches the target nucleus of copper (Z = 29) is such a way that the vlaue of impact parameter is zero. The distance of closest approach will be

An alpha-helix is a structural feature of

An alpha-amino acid exists as, overset(+)(NH_3)-underset(R)underset(|)CH-COOH at (pH=2) and its isoelectric point is 6. The amino acid at pH 10.97 will exist as :

An alloy which does not contain copper is :

Which of the following alloys does not contain copper?