52671 + Interview Questions in Chemistry in Class 11

1.	Among all the elements which one has the highest value of electronegativity?
Answer» Chlorine BROMINE Fluorine IODINE ANSWER :C

Discussion

2.	Among all the alkali metals only Na can react with nitrogen of air and can form nitride.
Answer» SOLUTION :FALSE statement (only LI can react with nitrogen of air and can form nitride, `Li_(3)N`.)

Discussion

3.	Among all alkali metals ........... is radioactive element."
Answer» SOLUTION :FRANCIUM

Discussion

4.	Among alkali metals which element do you expect to be least electronegative and why?
Answer» SOLUTION :ELECTRONEGATIVITY decreases in a group from TOP to bottom. THUS, caesium is the least electronegative element.

Discussion

5.	Among all alkali metal ions ……………… having highest ionization enthalpy.
Answer» SOLUTION :`LI^(+)`

Discussion

6.	Among alkali metal salts, the lithium salts are the poorest conductors of electricity in aqueous solution because of
Answer» EASY diffusion of `LI^(+)` ions Lower ability of `Li^(+)` ions to polarize water molecules LOWEST charge to RADIUS ratio Higher degree of hydration of `Li^(+)` ions Answer :D

Discussion

7.	Amongalkalimetalswhichelementdo youexpect tobe leastelectronegativeand why ?
Answer» SOLUTION :Electronegativitydecreasesas the SIZEOF atomincreases. SinceFrhasthe largestsizethereforeit hasthe leastelectronegativity.

Discussion

8.	Among Al_2O_3, SiO_2, P_2O_3 and SO_2 the correct order of acid strength is
Answer» `Al_2O_3 LT SiO_2 lt SO_2 lt P_2O_3` `SiO_2 lt SO_2 lt Al_2O_3 lt P_2O_3` `SO_2 lt P_2O_3 lt SiO_2 lt Al_2O_3` `Al_2O_3 lt SiO_2 lt P_2O_3 lt SO_2` ANSWER :D

Discussion

9.	Among a) Na_(2)O_(2) ,b) MgO, c) Al_2O_3 : d) P_2O_5 and e) Cl_2O_7 the most basic, most acidic and amphoteric oxide can be
Answer» a,b,C b,e,c a,e,c e,c,a Answer :C

Discussion

10.	Amog SO_(2),H_(2)SO_(4) and sodium thiosulphate, the sulphur has the highest oxidation state in ...............
Answer» SOLUTION :`H_(2)SO_(4)`

Discussion

11.	Ammonium dichromate upon heating decomposes to give nitrogen gas and chromium oxide is it a redox reaction ? If so what is the type of the redox whether inter or introamolecular
Answer» Solution :Hre O.N of N increase from -3 to 0 in `N_(2)` THEREFORE it is oxidised in contrast the O.N of Cr DECREASE from +6 to +3 in `Cr_(2)O_(3)` therefore it is reduced thus it is an interamolecular REDOX reaction SINCE both the SPECIES cation and the anion are part of the same compountd ammonium dichromate

Discussion

12.	Ammonium carbamate when heated tto 200^(@)C gives a mixture of NH_(3) and CO_(2) vapour with a density of 13. what is the degree of dissociation of ammonium carbamate?
Answer» `(3)/(2)` `(1)/(2)` `2` 1 Answer :D

Discussion

13.	Ammonium carbamate when heated to 200^(@) Cgives a mixture of NH_(3) and CO_(2) vapours with a density of 16*0 . What is the degree of disociation of ammonium carbamate ?
Answer» `3//2` `1//2` 2 1 Solution :`{: (,NH_(2)COONH_(4),to,2NH_(3),+,CO_(2)), ("Intial" ,1"mole",,,,), ("After disso.",1-alpha,,2ALPHA,,alpha ),(,,,,,"Total"=1+2 alpha):}` Theoretical density `(D) propto 1/V ` OBSERVED density ` (d) propto 1/((1+2alpha)V)` ` :. D/d = 1+ 2 alpha ` or ` alpha = 1/2 ((D-d)/d) = 1/2 ((48-160)/160) =1*0 `

Discussion

14.	Ammonium carbamate (NH_2COONH_4)decomposes as: NH_2COONH_4(s) hArr 2NH_3(g) + CO_2(g) In a closed vessel containing ammonium carbamate in equilibrium, ammonia is added such that partial pressure of NH_3 becomes equal to original total pressure. Calculate the ratio of final total pressure to the original pressure.
Answer» Solution :SUPPOSE the total pressure of the mixture initially is p. This is DUE to the PARTIAL pressure of `NH_3` and `CO_2` which are present in the ratio of 2:1. `p(NH_3)=2/3p` and `p(CO_2)=1/3p` `THEREFORE K_p=p(NH_3)^2 xx p(CO_2)=(2/3p)^2XX(1/3p)=4/27p^3` After adding`NH_3 , p(NH_3)=p` (given) `therefore p^2xxp(CO_2)=K_p=4/27p^3` `therefore p(CO_2)=4/27p` Final total pressure =`p(NH_3)+p(CO_2)=p+4/27p =31/27p` `therefore` Ratio of final total pressure to the original pressure =31:27

Discussion

15.	Ammonium carbamate dissociates as : NH_(2)COONH_(4)(s) hArr 2NH_(3)(g) + CO_(2)(g) , In a closed vessel containing ammonium carbamate, at equilibrium, CO_(2) is added such that partial pressure of CO_(2) now equals three times the original total pressure. Calculate the ratio of total pressure now to the original pressure :
Answer» `(31)/(27)` `(11)/(9)` `(27)/(31)` `(29)/(9)` ANSWER :D

Discussion

16.	Ammonium carbamate decompses as NH_(2) COONH_(4) (s) hArr 2 NH_(3) (g) + CO_(2) (g) . In a closed vessel containing ammonium carbamate in equilibrium , NH_(3) is added such that the partial pressure of NH_(3) now equals original total pressure. Calculate the ratio of total pressure not to the original pressure.
Answer» Solution :the RATIO of 2 :1 Thus, ` p_( NH_(3)) = 2/3 P, p_(CO_(2))= 1/3 P :. K_(P) = (p_(NH_(3)))^(2) (p_(CO_(2)))^(2) = (2/3P)^(2) (1/3 P) = 4/27 P^(3)` After ADDING ` NH_(3) , p_(NH_(3))= P("GIVEN "):. P^(2) XX p_(CO_(2))= K_(p) = 4/27 P^(3) or p_(CO_(2)) = 4/ 27 P` `:. " Total pressure now " = p_(NH_(3))+ p_(CO_(2))= P + 4/27 P = 31/27 P` `:." Ratioof totalpressure now to the original pressure "= 31 /27 .`

Discussion

17.	Ammonical silver nitrate reacts with
Answer» ethyne ethylene butyne-1 butyne-2 Answer :A::C

Discussion

18.	Ammonical AgNO_(3) gives white ppt after reaction with any compound then this reflects the presence of
Answer» ONE-CHO GROUP One tripe bond A terminal alkylene Compound is unsaturated Answer :C

Discussion

19.	Ammonia under a pressure of 1.5 atm at 27^(@)C is heated to 374^(@)C in a closed vessel in the presence of a catalyst. Under the conditions, NH_(3) is partially decomposed according to the equation. 2NH_(3) hArr N_(2) + 3H_(2) the vessel is such that the volume remains etfectively constant where as pressure increases to 50 atm. Calculate the percentage of NH_(3) actually decomposed
Answer» 0.065 0.613 0.625 0.64 Solution : Initial pressure of `NH_(3)` of .a. Mole = 15 atm at `27^(@)C` The pressure of .a. mole of `NH_(3)`=p atm at = `347^(@)C` `(P_(1))/(T_(1))=(P_(2))/(T_(2)), (15)/(300)=(P)/(629) implies p =31` atm At constant volume and at `347^(@)C` mole `alpha` pressure a `alpha` 31 (before equilibrium) `(a+2alpha)alpha50` (at equilibrium) `(a+2alpha)/(a)=(50)/(31) implies x=(19a)/(62) implies %NH_(3)` decomposes `=(2x)/(a) XX 1000, (2 xx 19a)/(62 xx a) xx 100=61.3%`

Discussion

20.	Ammonia produced when 0.75 g of a substance was kjeldahlised neutralised 30 cm^(3) of 0.25 NH_(2)SO_(4). Calculate the persentage of nitrogen in the compound.
Answer» Solution :MASS of the organic SUBSTANCE =0.75 g Volume of `H_(2)SO_(4)` USED up `=30 cm^(3)` Normality of sulphuric acid `= 0.25 N` `30 cm^(3)` of `H_(2)SO_(4)` of normality `0.25 N equiv 30 cm^(3)` of `NH_(3)` solution of normality 0.25 N But `1000 cm^(3)` of ammonia solution of normality 1 contain 14 g of nitrogen. `:.` Therefore, `30 cm^(3)` of 0.25 N ammonia solution will contain nitrogen `=14/1000xx30xx0.25` `:.` Percentage of nitrogen `=("Mass of nitrogen")/("Mass of substance")xx100=14/1000xx(30xx0.25)/(0.75)xx100=14.00`.

Discussion

21.	Ammonia obtained from 0.4 g of organic substance by Kjeldahl's method was absorbed in 30 mL of 0.25 M H_(2)SO_(4). The excess of the acid was neutralized by the addition of 30 mL of 0.2 M NaOH. Calculate the percentage of nitrogen in the substance.
Answer» ANSWER :`31.5%`

Discussion

22.	Ammonia is oxised by oxygen to give nitric oxide and water. The weight of water produced per gram of nitric oxide is 0.1xx xg. What is value of d.
Answer» Solution :`2NH_(3)+(5)/(2)O_(2)rarrunderset(60G)(2NO)+underset(54g)(3H_(2)O)`

Discussion

23.	Ammonia is more soluble than oxygen in water. Why ?
Answer» SOLUTION :Ammonia forms hydrogen bonding with water molecules, this intermolecular bonds are very strong and thus the ammonia is more soluble in water. Ammonia is STRONGLY interact with water to form ammonium hydroxide. But oxygen is more ELECTRONEGATIVE it is not able to interact with water more. So `NH_(3)` is more soluble than `O_(2)` in water.

Discussion

24.	Ammonia is a good complexing agent. Give reasons. Or Ammonia acts as a ligand. Explain.
Answer» Solution :Due to the presence of a lone pair of electrons on N, `NH_(3)` ACTS as a complexing agent (ligand). As a result, it combines with transition metal cations to formcomplexes. For example : `underset("Silver chloride")(AgCl)+2NH_(3)tounderset("Diamminesilver (I) chloride")([Ag(NH_(3))_(2)]Cl),underset("Copper SULPHATE")(CuSO_(4))+4NH_(3)tounderset("Tetraamminecopper (II) sulphate")([Cu(NH_(3))_(4)]SO_(4)),underset("Chromium chloride")(CrCl_(3))+6NH_(3)tounderset("Hexaamminechromium (III) chloride")([Cr(NH_(3))_(6)]Cl_(3))`

Discussion

25.	Ammonia gas diffuses twice as fast as gas X. The gas 'X'is
Answer» `SO_2` `C_4 H_(10)` `C_5 H_8` `Cl_2` ANSWER :C

Discussion

26.	Ammonia gas diffuses through a fine hole at the rate 0.5 lit min^-1. Under the same conditions find the rate of diffusion of chlorine gas.
Answer» ANSWER :0.245 lit/min

Discussion

27.	Ammonia forms the complex [Cu(NH_(3))_(4)]^(2+) withcopper ion in alkaline solution but not in acidic solution. This is due to the reason that :
Answer» in alkaline solution insoluble `Cu(OH)_(2)` is PRECIPITATED which is SOLUBLE in EXCESS of any alkali `Cu(OH)_(2)` is amphoteric in acidic solution hydration protects `Cu^(2+)` ion in acidic solution, proton coordinates with `NH_(3)` forming `NH_(4)^(+)` ion and `NH_(3)` is not available Solution :It is the correct answer. `OVERSET(..)(N)H_(3) + underset(("ACID"))(H^(+)) rarr NH_(4)^(+)` Lone pair is not available for co-ordination with `Cu^(2+)` ion

Discussion

28.	Ammonia acts as an acid to sodium. Substantaite.
Answer» Solution :Acid on TREATING with an active metal LIBERATES hydrogen. Ammonia also liberates hydrogen on heating with SODIUM metal.

Discussion

29.	Amixture of caustic soda and soda ash requires 25ml 1M HCl for phenolphthalein indicatorand 35ml of 1M HCl for methyl orange indicator. Calculate ratio of (a) number of equivalent and (b) number of moles of the component in the mixture.
Answer» Solution :For phenolphthalein indicator :`NaOH +HCl to NaCl +H_(2)O` `Na_(2)CO_(3)+HCI to NaCl +NaHCO_(3)` n=1 for NaOH and n=1 for `Na_(2)CO_(3)` For methyl orange indicator : `NaOH +HCl to NaCl +H_(2)O` `Na_(2)CO_(3)+2HClto2NaCl +H_(2)O +CO_(2)` n=1 for NaOHand n=2 for `Na_(2)CO_(3)` If x=number of m.eq. of NaOH and y=number of m.eq of `Na_(2)CO_(3)` `x+y=25 "" x+2y=35` Solving the values of x and y , y=10, x=15 (a)Ratio of equivalents of NaOH and`Na_(2)CO_(3)` in the mixture = 15:10=3:2 (B) Ratio of MOLES of NaOH and `Na_(2)CO(3)` in the mixture =15:5=3:1

Discussion

30.	Amit was asked by his teacher to separate a liquid mixture of acetone and ethyl alcohol. He set up a distillation apparatus and tried to distil the mixture. To his surprise, both the liquids got distilled. Teacher told Amit to repeat the experiment by using a fractionating column in the distillation flask. Amit followed the advice of the teacher and was able to separate the two liquids. (i) Why was Amit not successful in separating the liquid mixture earlier ? (ii) Why did teacher ask him to use the fractionating column ? (iii) Which liquid was distilled first ? (iv) As a student of chemistry, what value based information you have gathered ?
Answer» Solution :(i) The DIFFERENCE in boiling point temperatures of acetone `(56^(@)C)` and ethyl ALCOHOL `(78^(@)C)` is only `22^(@)C`. Therefore, process of simple DISTILLATION fails in this case. (ii) Fractionating column is quite effective in this case because it obstructs the distillation of ethyl alcohol which is high boiling and at the same time helps in the distillation of acetone which is low boiling. (iii) Acetone was distilled first SINCE it has comparatively low boiling point. (iv) The process of simple distillation can be used in case the liquids present in the mixture differ in their boiling points by at least by `30^(@)C` or more.

Discussion

31.	Amino grup is ortho, para-directing for aromatic electrophilic substitution, On nitration of aniline, a good amount of m-nitroaniline is obtained. This is due to :
Answer» in nitration MIXTURE, ortho-, para-activity of `-NH_(2)` GROUP is COMPLETELY LOST `-NH_(2)" bencomes " NH_(3)^(+),"which is m-directing"` `-NH_(2)" bencomes "-NH^(+)SO__(4)^(-), "which is m-directing"` `-NH_(2)" bencomes "-NH^(-)SO_(4)^(-)," which is m-directing "` Answer :b

Discussion

32.	Amino acids are synthesised from
Answer» `ALPHA`-Halo acids by reaction with `NH_(3)` Aldehydes by reaction with `NH_(3)` and cyanide ion followed by hydrolysis. Alkyl halides by reaction with the ENOLATE anion derived from diethyl acetamidomalonate & hydrolysis Alcohols by reaction with `NH_(3)` and `CN^(-)` ion followed by hydroysis. Solution :The hydrogen ion concentration of the solution in which a particular amino acid does not migrate under the influence of an ELECTRIC field is called the isoelectric point (pI) of that amino acid. The isoelectric point (pI) is the pH at which the amino acid exists only as a dipolar ion with net charge zero.

Discussion

33.	(a)M_((g))^(-) to M_((g)) , (b)M_((g)) to M_((g))^(+) , (c)M_((g))^(+) to M_((g))^(2+) , (d)M_((g))^(2+) to M_((g))^(3+) Minimum and maximum I.P. would be of :
Answer» a b c d Answer :A::D

Discussion

34.	Ametal oxide contains 53% of metal by weight. What is the equivalent weight of metal?
Answer» ANSWER :9

Discussion

35.	Alveoli are tiny sacs in the lungs whole average diameter is 5 xx 10^(-10)m , an oxygen molecule (mass 5.6 xx 10^(-25)kg) is trapped in a sac the uncertainty in the velocity of oxygen molecule within a sac is:
Answer» 2.0 m/sec 3.0 m/sec 1.0 m/sec 4.0 m/sec Solution :Average diameter of Alveoli = `5 A^@` and `DELTA v ge h/(4pi m . Delta X)`

Discussion

36.	Aluminium vessels should not be washed with materials containing washing soda since:
Answer» washing SODA reacts with ALUMINIUM to form SOLUBLE ALUM inum washing soda is expensive washing soda is easily decomposed washing soda reacts with aluminium to form insoluble aluminium oxide. Answer :A

Discussion

37.	Aluminium vessels should not be washed with materials containing washing soda because
Answer» SOLUTION :WASHING soda undergoes hydrolysis to give alkali. `Na_2CO_3+2H_2O to H_2CO_3+2NaOH` Sodium hydroxide REACTS with ALUMINIUM vessels.

Discussion

38.	Aluminium trifluoride is insoluble in anhydrous HF but dissolves on addition of NaF.Aluminium trifluoride precipitates out of theresultingsolution when gaseousBF_(3) is bubbled through. Give reasons.
Answer» SOLUTION :(i) Anhydrous `HF` is a covalent compoundand is strongly `H`-bonded. Therefore , it does not give `F^(-)` ions and hence `AlF_(3)` does notdissolve in `HF`. In contrast,`NAF`beingan ionic compound contains `F^(-)`ions andhence combineswith `AlF_(3)`to FORM the soluble complex. `3NaF + AlF_(3) rarr UNDERSET((" soluble complex "))underset(" Sod. hetrafluoroborate (III) ")(3Na [BF_(4)]) + AlF_(3) (s)` (ii) Because of smaller size and higher electronegativity, has high MUCH higher tendency to form complexes than Al, therefore when `BF_(3)` is added to the above solution. `AlF_(3)` gets precipitated.

Discussion

39.	Aluminium trifluoride is insoluble in anhydrous HF but dissolves on addition of NaF. Aluminium trifluoride precipitates out of the resulting solution when gaseous BF_(3) is bubbled through. Give reasons.
Answer» Solution :AlF3 does not dissolve in anhydrous HF because HF is a covalent compound and is strongly HYDROGEN bonded. NaF is an ionic compound and provides `F^-` IONS which combine with `AlF_3` to form a soluble complex, `Na_3 [AlF_6]`. Therefore, `AlF_3` DISSOLVES in presence of NaF. `3NaF + AlF_3 to underset("Sodium hexafluoroaluminate (III)")(Na_3 [ AlF_6])` When gaseous `BF_3` is bubbled through the RESULTING solution, boron because of its smaller size and higher electronegativity, enters into the complex and expels aluminium. Thus, `AlF_3`gets precipitated. `Na_3 [AlF_6] + 3BF_3 to underset("Sod. TETRAFLUOROBORATE (III) (soluble)")(3Na[BF_4]) + underset("insoluble")(AlF_3) darr`

Discussion

40.	Aluminium trifluoride is insoluble in anhydrous HF but dissolves on addition of NaF. Aluminium trifluoride precipitates out of the resulting solution when gaseous BF_3 is bubbled through. Give reasons.
Answer» Solution :Hydrogen fluoride (HF) is a covalent compound and has a very strong intermolecular hydrogen bonding. Thus, it does not provide ions and ALUMINIUM fluoride (AlF) does not DISSOLVE in it. Sodium fluoride (NaF) is an ionic compound and when it is added to the mixture, AlF dissolves. This is because of the availability of free `F^-`. The reaction involved in the PROCESS is : `3NaF+ AlF_3 to underset"Soluble complex"(Na_3 [AlF_6])` When boron trifluoride `(BF_3)` is added to the solution, aluminium fluoride precipitates out of the solution. This happens because the tendency of boron to form complexes is MUCH more than that of aluminium. Therefore, when `BF_3` is added to the solution, B replaces Al from the complexes according to the following reaction. `Na_3[AlF_6] 3BF_3 to underset"Soluble complex"(3Na[BF_6])+ underset"Precipitate"(AlF_3)`

Discussion

41.	Aluminium reacts with hydrogen chloride to produce H_2 according to the equation 2Al+6HCl to 2ACl_(3)+3H_(2) Then 2grams of H_2 would be produced from
Answer» 1 MOLE of Al 2 MOLES of Al 2/3 mole of Al 3/2 mole of Al Answer :C

Discussion

42.	Aluminium reacts with concentrated HCl and concentrated NaOH to liberate the gases.........respectively.
Answer» `H_(2)` and `O_(2)` `O_(2)` and `H_(2)` `H_(2)` and `H_(2)` `O_(2)` and `O_(2)` Solution :`2AL+6HCl RARR 2AlCl_(3) +3H_(2)` `2Al + 2NaOH + 2H_(2)O rarr 2NaAlO_(2)+3H_(2)`

Discussion

43.	Aluminium reacts with concentrated H_(2)SO_(4) to liberate SO_(2) gas. In this process, the clement in H_(2)SO_(4) that has changed its oxidation state is
Answer» H S O none Answer :B

Discussion

44.	Aluminium power is used in
Answer» The extraction of gold Calico-printing Sizing PAPER In FLASH BULBS SOLUTION :In flash bulbs

Discussion

45.	Aluminium oxide is not reduced by chemical reactions since
Answer» ALUMINIUM oxide is HIGHLY stable aluminium oxide is reactive reducing AGENTS contaminate the PROCESS pollutes the environment. Solution :Aluminium cannot easily be reduced by chemical REDUCTION as aluminium oxide is highly stable.

Discussion

46.	Aluminium oxide contains 52.90% aluminium and carbon dioxide contains 27.27% carbon. Calculate the percentage of aluminium in aluminium carbide assuming that the law of reciprocal proportions is true.
Answer» ANSWER :`75%`

Discussion

47.	Aluminium oxide contains 52.9 % aluminium and carbon dioxide contains 27.27 % carbon. Assuming that the law of Reciprocal proportions is true, calculate the percentage of aluminium in aluminium carbide.
Answer» Solution :Let US fix `1g` of oxygen with `Al = 52.9 g` In `Al_(2)O_(3),47.1 g` of O are combined with `Al = 52.9 g` `:. 1.0` g of O is combined with `Al=(52.9)/(47.1)g=1.123g` In `CO_(2),72.73 g` of O are combined with `C = 27.27 g` `:.` 1.0 g of O is combined with `C=(27.27)/(72.73)g=0.375g` The ratio by weight of aluminium and carbon combining with a fixed weight of oxygen in the TWO oxides `1.123 : 0.375` Since the Law of reciprocal proportions is truem aluminium and carbon in aluminium CARBIDE will combine either in the same ratio or in simple multiple ratio of their weights `:.` Percentage of `Al` in `Al_(4)C_(3)=(1.123)/(1.123+0.375)xx100=(1.123)/(1.495)xx100=74.97%`.

Discussion

48.	Aluminium metal forms a cubic close-packed crystal structure. Its atomic radius is 125xx10^(-12)m. (a) Calculate the length of the side of the unit cell. (b) How many such unit cells are there in 1.00 m^3 of aluminium ?
Answer» Solution :ccp=fcc. For fcc, `r=a/(2sqrt2)` or `a=2sqrt2r=2xx1.414xx125xx10^(-2) m =354xx10^(-12) m`=354 PM VOLUME of one unit CELL =`(354xx10^(-12)m)^3=4.436xx10^(-29) m^3` `therefore` No. of unit cell in 1 `m^3=1/(4.436xx10^(-29))=2.25xx10^28`

Discussion

49.	Aluminium metal is corroded in coastel places near to
Answer» is removed by sea WATER reacts with sea water is ATTACKED by salt present in sea water reacts with sand particles Solution :(c ) It is a RESON for GIVEN fact.

Discussion

50.	Aluminium metal forms a cubic close - packed crystal astucture. Its atomic radius is125 xx 10^(-12)m. (a) Calculatethe length of the side of the unit cell. (b) hwo many such unit cells are there in 1.00 m^(3)of aluminium ?
Answer» SOLUTION :ccp = fcc. For fcc, `r = a/(2sqrt(2))or a = 2 sqrt2r = 2 xx 1.414 xx 125 xx 10^(-2) m = 354 xx10^(-12) m =354 "pm"` No. of unit cell in ` 1 m^(3)= 1/(4.436 xx 10^(-29))= 2.25 xx 10^(-29) m^(3)` No. of unit cells in ` 1M ^(3) = 1/( 4.436 xx 10^(-29)) = 2.25 xx 10^(28)`

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Among all the elements which one has the highest value of electronegativity?

Among all the alkali metals only Na can react with nitrogen of air and can form nitride.

Among all alkali metals ........... is radioactive element."

Among alkali metals which element do you expect to be least electronegative and why?

Among all alkali metal ions ……………… having highest ionization enthalpy.

Among alkali metal salts, the lithium salts are the poorest conductors of electricity in aqueous solution because of

Amongalkalimetalswhichelementdo youexpect tobe leastelectronegativeand why ?

Among Al_2O_3, SiO_2, P_2O_3 and SO_2 the correct order of acid strength is

Among a) Na_(2)O_(2) ,b) MgO, c) Al_2O_3 : d) P_2O_5 and e) Cl_2O_7 the most basic, most acidic and amphoteric oxide can be

Amog SO_(2),H_(2)SO_(4) and sodium thiosulphate, the sulphur has the highest oxidation state in ...............

Ammonium dichromate upon heating decomposes to give nitrogen gas and chromium oxide is it a redox reaction ? If so what is the type of the redox whether inter or introamolecular

Ammonium carbamate when heated tto 200^(@)C gives a mixture of NH_(3) and CO_(2) vapour with a density of 13. what is the degree of dissociation of ammonium carbamate?

Ammonium carbamate when heated to 200^(@) Cgives a mixture of NH_(3) and CO_(2) vapours with a density of 16*0 . What is the degree of disociation of ammonium carbamate ?

Ammonical silver nitrate reacts with

Ammonical AgNO_(3) gives white ppt after reaction with any compound then this reflects the presence of

Ammonia produced when 0.75 g of a substance was kjeldahlised neutralised 30 cm^(3) of 0.25 NH_(2)SO_(4). Calculate the persentage of nitrogen in the compound.

Ammonia obtained from 0.4 g of organic substance by Kjeldahl's method was absorbed in 30 mL of 0.25 M H_(2)SO_(4). The excess of the acid was neutralized by the addition of 30 mL of 0.2 M NaOH. Calculate the percentage of nitrogen in the substance.

Ammonia is oxised by oxygen to give nitric oxide and water. The weight of water produced per gram of nitric oxide is 0.1xx xg. What is value of d.

Ammonia is more soluble than oxygen in water. Why ?

Ammonia is a good complexing agent. Give reasons. Or Ammonia acts as a ligand. Explain.

Ammonia gas diffuses twice as fast as gas X. The gas 'X'is

Ammonia gas diffuses through a fine hole at the rate 0.5 lit min^-1. Under the same conditions find the rate of diffusion of chlorine gas.

Ammonia forms the complex [Cu(NH_(3))_(4)]^(2+) withcopper ion in alkaline solution but not in acidic solution. This is due to the reason that :

Ammonia acts as an acid to sodium. Substantaite.

Amixture of caustic soda and soda ash requires 25ml 1M HCl for phenolphthalein indicatorand 35ml of 1M HCl for methyl orange indicator. Calculate ratio of (a) number of equivalent and (b) number of moles of the component in the mixture.

Amino grup is ortho, para-directing for aromatic electrophilic substitution, On nitration of aniline, a good amount of m-nitroaniline is obtained. This is due to :

Amino acids are synthesised from

(a)M_((g))^(-) to M_((g)) , (b)M_((g)) to M_((g))^(+) , (c)M_((g))^(+) to M_((g))^(2+) , (d)M_((g))^(2+) to M_((g))^(3+) Minimum and maximum I.P. would be of :

Ametal oxide contains 53% of metal by weight. What is the equivalent weight of metal?

Alveoli are tiny sacs in the lungs whole average diameter is 5 xx 10^(-10)m , an oxygen molecule (mass 5.6 xx 10^(-25)kg) is trapped in a sac the uncertainty in the velocity of oxygen molecule within a sac is:

Aluminium vessels should not be washed with materials containing washing soda since:

Aluminium vessels should not be washed with materials containing washing soda because

Aluminium trifluoride is insoluble in anhydrous HF but dissolves on addition of NaF.Aluminium trifluoride precipitates out of theresultingsolution when gaseousBF_(3) is bubbled through. Give reasons.

Aluminium trifluoride is insoluble in anhydrous HF but dissolves on addition of NaF. Aluminium trifluoride precipitates out of the resulting solution when gaseous BF_(3) is bubbled through. Give reasons.

Aluminium trifluoride is insoluble in anhydrous HF but dissolves on addition of NaF. Aluminium trifluoride precipitates out of the resulting solution when gaseous BF_3 is bubbled through. Give reasons.

Aluminium reacts with hydrogen chloride to produce H_2 according to the equation 2Al+6HCl to 2ACl_(3)+3H_(2) Then 2grams of H_2 would be produced from

Aluminium reacts with concentrated HCl and concentrated NaOH to liberate the gases.........respectively.

Aluminium reacts with concentrated H_(2)SO_(4) to liberate SO_(2) gas. In this process, the clement in H_(2)SO_(4) that has changed its oxidation state is

Aluminium power is used in

Aluminium oxide is not reduced by chemical reactions since

Aluminium oxide contains 52.90% aluminium and carbon dioxide contains 27.27% carbon. Calculate the percentage of aluminium in aluminium carbide assuming that the law of reciprocal proportions is true.

Aluminium oxide contains 52.9 % aluminium and carbon dioxide contains 27.27 % carbon. Assuming that the law of Reciprocal proportions is true, calculate the percentage of aluminium in aluminium carbide.

Aluminium metal forms a cubic close-packed crystal structure. Its atomic radius is 125xx10^(-12)m. (a) Calculate the length of the side of the unit cell. (b) How many such unit cells are there in 1.00 m^3 of aluminium ?

Aluminium metal is corroded in coastel places near to

Aluminium metal forms a cubic close - packed crystal astucture. Its atomic radius is125 xx 10^(-12)m. (a) Calculatethe length of the side of the unit cell. (b) hwo many such unit cells are there in 1.00 m^(3)of aluminium ?