52671 + Interview Questions in Chemistry in Class 11

1.	The ratio between the number of molecules in equal masses of nitrogen and oxygen is
Answer» `7:8` `1:9` `9:1` `8:7` ANSWER :D

Discussion

2.	The ratio between the number of molecules in equal masses of CH_(4) and SO_(2) is
Answer» `1:1` `4:1` `1:4` `2:1` ANSWER :B

Discussion

3.	The ratio between the number of atoms in equal volumes of oxygen and ozone under the same conditions is
Answer» `3: 2` `2 : 3` `1 : 1` `1 : 2` ANSWER :B

Discussion

4.	The ratio between the number of atoms in equal masses of Hydrogen and Helium is
Answer» `1:2` `2:1` `1:4` `4:1` ANSWER :D

Discussion

5.	The ratio between the neutrons present in carbon atom and silicon atoms with mass numbers 12 and 28 is
Answer» `7:3` `3:7` `1:2` `2:1` SOLUTION :n(n) in C = 6 n (n) in SI= 14 `IMPLIES (6)/(14) =(3)/(7)`

Discussion

6.	The rate of the reaction depends on the concentration of
Answer» `Cl_(2)` `FeCl_(3)` Solution :General RATE EQUATION for halogenation [rate=k`[C_(6)H_(6)][Cl_(2)][FeCl_(3)]`]

Discussion

7.	The rate of the reaction : 2N_(2)O_(5)rarr4NO_(2)+O_(2) can be written in three ways. (1)/(4)(-d[N_(2)O_(5)])/(dt)=k[N_(2)O_(5)],(d[NO_(2)])/(d)=k'[N_(2)O_()](d[NO_(2)])/(d)=k'[N_(2)O_(5)] The relationship between K and K' and between K' and K' becomes
Answer» `K'=2K , K''=K'` `K'=2K ,K''= K//2` `K' = 2K , K'' = 2K'` `K' = K, K'' = K` SOLUTION :`2N_(2)O_(5)rarr4NO_(2)+O_(2)` `-(1)/(2)(d[N_(2)O_(5)])/(dt)+(1)/(4)(d[NO_(2)])/(dt)=(d[O_(2)])/(dt)`

Discussion

8.	The rate of esterification of alcohols is more for
Answer» `CH_(3)OH` `C_(2)H_(5)OH` `(CH_(3))_(2)CHOH` `(CH_(3))_(3)COH` Solution :Lesser is stearic HINDERANCE, greater is the rate of esterification.

Discussion

9.	The rate of elimination is fastest in
Answer» `Ph-CH_2-CH_2-F` `Ph-undersetunderset(O)(\|\|)C-CH_2-CH_2-F` `Ph-O-CH_2-CH_2-F` `CH_3-CH_2-CH_2-F` ANSWER :B

Discussion

10.	The rate of effusion of two gases 'a' and 'b' under identical conditions of temperature and pressure are in the ratio of 2:1. What is the ratio of rms velocity of their molecules if T_a and T_bare in the ratio of 2:1
Answer» `2:1` `SQRT(2)`:1 `2sqrt(2):1` `1:sqrt(2)` Solution :`(gamma_a)/(gamma_b) = sqrt((M_b)/(M_a)) = 2/1 implies M_b = 4M_a`. `((U_(rms))_(a))/((U_(rms))_b) = sqrt((T_a )/(T_b XX M_a)) = sqrt((2)/(1) xx 4/1) = 2sqrt(2) :1`.

Discussion

11.	The rate of diffusion of two gases at same volume are 8 and 12 sec. respectively. If gas A.s molecular weiht is 81 g/mol so what will be the molecular weight of gas B ?
Answer» 48.50 g/mol 182.25 g/mol 36 g/mol 72.0 g/mol ANSWER :B

Discussion

12.	The rate of diffusion of two gases A and B are in the ratio 16:3. if the ratio of their masses present in the mixture is 2:3 then:
Answer» The ratio of their molar MASSES is 16:1 The ratio of their molar masses is 4:1 The ratio of their moles PRESENT INSIDE the CONTAINER is 1:24 The ratio of their moles inside the container is 8:3 Answer :d

Discussion

13.	The rate of diffusion of oxygen is 12 cm^(3)s^(-1).Under similar conditions, what is the rate of diffusionof carbondioxide ?
Answer» SOLUTION :`10.93 CM^(3)s^(-1)`

Discussion

14.	The rate of diffusion of methane is twice that of the following gas under the same conditions
Answer» `O_3` `O_2` `SO_2` `SO_3` ANSWER :C

Discussion

15.	The rate of diffusion of methane at given temperature is twice that of unknown gas. The gas is
Answer» `C_2 H_6` `CO_2` `C_3 H_4` `SO_2` ANSWER :D

Discussion

16.	The rate of diffusion of methane at given temperature is twice that of gas 'X'. The Molecular weight of'X' is
Answer» 32 16 8 64 ANSWER :D

Discussion

17.	The rate of diffusion of Hydrogen is about
Answer» 1/2 that of He TWICE that of He 1.414 times that of He Four times that of He SOLUTION :`(gamma_(H_2))/(gamma_(He)) = sqrt(4/2) = sqrt(2) = 1.414`.

Discussion

18.	The rate of diffusion of a sample of ozonised oxygen is 0.98 times more than that of pure oxygen Find the percentage (by volume) of ozone in the ozonised sample Also report percentage by weight .
Answer» ANSWER :`8.25%` by VOLUME of `O_(3) 11.88%` by WEIGHT of `O_(3)` .

Discussion

19.	The rate of diffusion of gas is ________ to square root of their molecular mass.
Answer» INVERSELY proportional DIRECTLY proportional equal TWICE ANSWER :A

Discussion

20.	The rate of diffusion of a gas is directly proportional to the square root of ………………… .
Answer» ANSWER :TEMPERATURE, in K

Discussion

21.	The rate of diffusion of a gas is
Answer» DIRECTLY proportional to its density directly proportional to its MOLECULAR MASS directly proportional to the square ROOT of its molecular mass inversely proportional to the square root of its molecular mass ANSWER :D

Discussion

22.	The rate of diffusion of a gas having molecular weight just double of nitrogen gas is 56 m L s^(-1). The rate of diffusion of nitrgoen will be :
Answer» `79.19 ML s^(-1)` `112.0 mL s^(-1)` `56 mL s^(-1)` `90.0 mL s^(-1)` ANSWER :A

Discussion

23.	The rate of diffusion of 2 gases 'A' and 'B' are in the ratio 16:3. If the ratio of their masses present in the mixture is 2:3, then:
Answer» The ratio of their MOLAR MASSES is 16:1 The ratio of their molar masses is 1:4 The ratio of their moles present INSIDE the container 1:24 The ratio of their moles present inside the container 8:3 Answer :B,d

Discussion

24.	The rate of diffusion of a gas at constant temperature and pressure is a) Directly proportional to its density b) Directly proportional to square root of its molecular wt c) Inversely proportional to its square root of its vapour density d) Directly proportional to its RMS velocity
Answer» C,d a,b b,d b,c Answer :A

Discussion

25.	The rate of decay of a radioactive sample is R_(1) at time t_(1) and R_(2) at time t_(2). Calculate the mean liffe of sample.
Answer» ANSWER :`(t_(1) - t_(2))/(2.303 [LOG R_(2) - log R_(1)])`

Discussion

26.	The rate of an S_(N)2 reaction depends upon the
Answer» NUCLEOPHILE CARBON skeleton leaving GROUP. all ANSWER :D

Discussion

27.	The rate of a stoichiometric reaction between a solid and gas in a container may be increased by increasing all of the following factors EXCEPT the :
Answer» PRESSURE of the gas. temperature of the gas. volume of the container. surface AREA of the solid. Answer :C

Discussion

28.	The rate of a gaseous reaction triples when temperature is increased by 10^(@)C from 25^(@)C. The energy of activation of the reaction in kJ mol^(-1) will be
Answer» 410 735 514 205 Solution :`"log"(3K)/(k)=(E_(a))/(2.303xx8.314 "JK mol"^(-1))XX(298K-283K)/(298Kxx283K)` `:. log 3=(E_(a))/(19.15)xx(15)/(298 xx 283)` `0.4771 =(E_(a)xx15)/(19.15xx298xx283)` or `E_(a)=(0.4771xx19.15xx298xx283)/(15)` `=513.68"kJ mol"^(-1)`.

Discussion

29.	The rate equation found in Benzillic acid -Benzil rearrangement israte=k[Ph-CO-CO-Ph]^(a)[OH^(-)]^(b)thena+b is
Answer» SOLUTION :`a=1, b=1`

Discussion

30.	The rate constant for a forward reaction in a reversible reaction (K_(eq) =10^(6)) is 10^(2) . Calculate rate constant for its backward reaction
Answer» `10^(4)` `10^(-4)` `10^(-6)` `10^(6)` SOLUTION :`K_(C)=(K_(F))/(K_(b))`

Discussion

31.	The rare gas that is most abundant in the atmosphere is
Answer» He NE AR KR ANSWER :C

Discussion

32.	The rapid change of pH near the stoichiometric point of an acid-base titration is the basis of indicator detection. pH of the solution is related to ratio of concentration of conjugate acid. (HNn) and the base [In^(-)) forms of the indicator by the expression
Answer» `LOG.([In^(-)])/([In^(-)])= pK_(In) -PH` `log.([HIN^(-)])/([In^(-)])= pK_(In) -pH` `log.([HIn^(-)])/([In^(-)])= pH_(In) -pK_(In)` `log.([In^(-)])/([ H In^(-)])= pH_(In) -pK_(In)` Solution :`pH = pK_(a)+log. (["Conjugate base"])/(["ACID"])` `:. pH - pK_(In)=log. ([In^(-)])/([HIn])`

Discussion

33.	The radius of which of the hydrated ion is the highest
Answer» `Li_(aq)^(+)` `Na_(aq)^(+)` `K_(aq)^(+)` `Rb_(aq)^(+)` SOLUTION :`Li^(+)` having the smallest SIZE thus the size of is the HIGHEST

Discussion

34.	The radius of which of the following orbit is same as that of the first Bohr.s orbit of hydrogen atom?
Answer» `H^+ (n=2)` `LI^(2+) (n=2)` `Li^(2+) (n=3)` `Be^(3+) (n=2)` SOLUTION :`(n_1^2)/(Z_1) = (n_2^2)/(Z_2)`

Discussion

35.	The radius of which of the following orbit is same as that first Bohr's of hydrogen atom ?
Answer» `He^(+) (n =2)` `Li^(2+) (n =2)` `Li^(2+) (n = 3)` `Be^(3+) (n = 2)` SOLUTION :`r_(n) = (0.529 n^(2))/(Z) Å` `:. r_(1) (H) = (0.520 xx 1^(2))/(1) = 0.529 Å` `r_(2) (Be^(3+)) = (0.520 xx 2^(2))/(4) = 0.529 Å`

Discussion

36.	The radius of which of the following orbit is same
Answer» `He^(+)` (n=2) `LI^(2+)(n=2)` `Li^(2+)(n=3)` `Be^(3+)(n=2)` ANSWER :D

Discussion

37.	The radius of the second Bohr orbit for hydrogen atom is (Planck's Const. h=6.6262xx10^(-34) Js, mass of electron = 9.1091xx10^(-31) kg , charge of electron e=1.60210xx10^(-19) C, permittivity of vacuum in_0=8.854185xx10^(-12) kg^(-1) m^(-3) A^2)
Answer» 4.76 Å 0.529 Å 2.12 Å 1.65 Å Solution :`R=0.529 n^2/z Å` `=0.529 2^2/1 Å` =2.12 Å

Discussion

38.	The radius of the second Bohr orbit for hydrogen atom is (Planck's constant, h = 6.6262 xx 10^(-34) Js mass of electron = 9.1091 xx 10^(-31) kg charge of electron, e = 1.60210 xx 10^(-19) C permitivity of the vacuum, in_(0) = 8.854185 xx 10^(-12) kg^(-1) m^(-3) A^(2))
Answer» `0.529 Å` `2.12 Å` `1.65 Å` `4.76 Å` SOLUTION :`r = a_(0) xx (N^(2))/(Z)` (`a_(0) =` Bohr radius) `:. r = 0.529 xx (2^(2))/(1) = 0.529 xx 4 Å = 2.12 Å`

Discussion

39.	The radius of the first orbit of hydrogen atom is 0.52 xx 10^(-8) cm. The radius of the first orbit of He^(+) ion is 0.26 xx 10^(-x)cm. Then the value of x is _______
Answer» SOLUTION :`r= (0.52xx10^(-8) xx 1^2)/(2) = 0.26xx10^(-8) cm`

Discussion

40.	The radius of the fourth orbit in hydrogen atom is 0.85 nm. Calculate the velocity of the electron in this orbit.
Answer» Solution :From Bohr.s postulates, the angular momentum is given as `mvr=(nh)/(2pi) or v=(nh)/(2pimr)` `n=4, m=9.1xx10^(-31)KG`. `r=0.85xx10^(-9)m` `v=(4xx6.625xx10^(-34)Js)/(2xx3.14xx9.1xx10^(-31)kgxx0.85xx10^(-9)m)` The velocity of electron in the 4th orbit `=5.45xx10^(5)ms^(-1)`

Discussion

41.	The radius of La^(3+) (Z=57) is 1.06A^(@). Which one of the following given values will be closest to the radius of Lu^(3+)
Answer» `0. 85 A^(0)` `1.60A^(0)` `1.40 A^(0)` `1.06A^(0)` ANSWER :A

Discussion

42.	The radius of the first Bohr orbit of hydrogen atom is 0.59 Å. The radius of the third orbit of He^(+) will be
Answer» `8.46 Å` `0.705 Å` `1.59 Å` `2.38 Å` SOLUTION :`r_(n) = (a_(0) n^(2))/(Z)= (0.59 B208Å xx 3^(2))/(2) = 2.38 B208Å`

Discussion

43.	The radius of the atom is of the order of
Answer» `10^(-10)CM` `10^(-13)cm` `10^(-15)cm` `10^(-8)cm` ANSWER :D

Discussion

44.	The radius of nucleus is approximately times smaller than the radius of atom.
Answer» 1,00,000 5000 10000 200 Answer :A

Discussion

45.	The radius of Na^(+) cation is less than that of Na atom. Give reason.
Answer» Solution :For the formation of cation, their is loss of an electron which means its RADIUS decreases. Due to decrease in no. of electrons nuclear FORCES increases pet electrons. As a RESULT, radius of cation decrease as the effective nuclear charge increases. e.g., ionic radius of Nat is smaller than that of PARENT atom Na. `Na to Na^(+)+ 1e^(-)` `{:("Electrons",11,10),("Nuclear charge",11,11),("Ionic size",186 "pm", 95 "pm"):}` pm= PICO METER `=10^(-12) cm`

Discussion

46.	The radius of hydrogen atom in the ground state is 0.53 Å, the radius of Li^(2+) in the similar state is
Answer» `1.06 A^@` `0.265 A^@` `0.175 A^@` `0.53 A^@` SOLUTION :`R = (n^2)/(Z) (0.529) A^@ , ` for `LI^(2+) (Z=2) , n=1`

Discussion

47.	The radius of first Bohr.s orbit for hydrogen is 0.53Å. The radius of third Bohr.s orbit would be
Answer» `0.79 A^@` `1.59A^@` `3.18 A^@` `4.77 A^@` SOLUTION :`R= (n^2)/(Z) (0.529) A^@ = 0.529 XX 3^2 = 4.77 A^@`

Discussion

48.	The radius of electron in the first excited state of hydrogen atom is
Answer» `a_0` `4a_0` `2a_0` `8a_0` SOLUTION :`R PROP n^2`(EXCITED STATE n=2) `r=4a^0`

Discussion

49.	The radius of certain orbit of H-atom is 2.12 A. Then the energy of that energy level is
Answer» `-(13.6)/(4)` eV/atom `(2.18xx10^(-18))/(4) ` J/atom `(-1312(/(4)` KJ/atom `(-1313.6)/(4)` Kcal/mole Solution :The radius of CERTAIN ORBIT of H-atiom is `2.12 A^@` . Then the energy of that energy level is `(-13.6)/(4) `eV/atom ,` (-2.18 xx 10^(-18))/(4)` J/atom `(-313.6)/(4) `Kcal/mole

Discussion

50.	The radius of an Xeatom is 1.3 xx 10^(-8) cm A 100 cm^(3) container is filled with Xe at a pressure of 1.0 atm and a temperature of 273K Calculate the fraction of the volume that is occupied by Xe atoms .
Answer» ANSWER :`2.474 xx10^(-2)`

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

The ratio between the number of molecules in equal masses of nitrogen and oxygen is

The ratio between the number of molecules in equal masses of CH_(4) and SO_(2) is

The ratio between the number of atoms in equal volumes of oxygen and ozone under the same conditions is

The ratio between the number of atoms in equal masses of Hydrogen and Helium is

The ratio between the neutrons present in carbon atom and silicon atoms with mass numbers 12 and 28 is

The rate of the reaction depends on the concentration of

The rate of the reaction : 2N_(2)O_(5)rarr4NO_(2)+O_(2) can be written in three ways. (1)/(4)(-d[N_(2)O_(5)])/(dt)=k[N_(2)O_(5)],(d[NO_(2)])/(d)=k'[N_(2)O_()](d[NO_(2)])/(d)=k'[N_(2)O_(5)] The relationship between K and K' and between K' and K' becomes

The rate of esterification of alcohols is more for

The rate of elimination is fastest in

The rate of effusion of two gases 'a' and 'b' under identical conditions of temperature and pressure are in the ratio of 2:1. What is the ratio of rms velocity of their molecules if T_a and T_bare in the ratio of 2:1

The rate of diffusion of two gases at same volume are 8 and 12 sec. respectively. If gas A.s molecular weiht is 81 g/mol so what will be the molecular weight of gas B ?

The rate of diffusion of two gases A and B are in the ratio 16:3. if the ratio of their masses present in the mixture is 2:3 then:

The rate of diffusion of oxygen is 12 cm^(3)s^(-1).Under similar conditions, what is the rate of diffusionof carbondioxide ?

The rate of diffusion of methane is twice that of the following gas under the same conditions

The rate of diffusion of methane at given temperature is twice that of unknown gas. The gas is

The rate of diffusion of methane at given temperature is twice that of gas 'X'. The Molecular weight of'X' is

The rate of diffusion of Hydrogen is about

The rate of diffusion of a sample of ozonised oxygen is 0.98 times more than that of pure oxygen Find the percentage (by volume) of ozone in the ozonised sample Also report percentage by weight .

The rate of diffusion of gas is ________ to square root of their molecular mass.

The rate of diffusion of a gas is directly proportional to the square root of ………………… .

The rate of diffusion of a gas is

The rate of diffusion of a gas having molecular weight just double of nitrogen gas is 56 m L s^(-1). The rate of diffusion of nitrgoen will be :

The rate of diffusion of 2 gases 'A' and 'B' are in the ratio 16:3. If the ratio of their masses present in the mixture is 2:3, then:

The rate of diffusion of a gas at constant temperature and pressure is a) Directly proportional to its density b) Directly proportional to square root of its molecular wt c) Inversely proportional to its square root of its vapour density d) Directly proportional to its RMS velocity

The rate of decay of a radioactive sample is R_(1) at time t_(1) and R_(2) at time t_(2). Calculate the mean liffe of sample.

The rate of an S_(N)2 reaction depends upon the

The rate of a stoichiometric reaction between a solid and gas in a container may be increased by increasing all of the following factors EXCEPT the :

The rate of a gaseous reaction triples when temperature is increased by 10^(@)C from 25^(@)C. The energy of activation of the reaction in kJ mol^(-1) will be

The rate equation found in Benzillic acid -Benzil rearrangement israte=k[Ph-CO-CO-Ph]^(a)[OH^(-)]^(b)thena+b is

The rate constant for a forward reaction in a reversible reaction (K_(eq) =10^(6)) is 10^(2) . Calculate rate constant for its backward reaction

The rare gas that is most abundant in the atmosphere is

The rapid change of pH near the stoichiometric point of an acid-base titration is the basis of indicator detection. pH of the solution is related to ratio of concentration of conjugate acid. (HNn) and the base [In^(-)) forms of the indicator by the expression

The radius of which of the hydrated ion is the highest

The radius of which of the following orbit is same as that of the first Bohr.s orbit of hydrogen atom?

The radius of which of the following orbit is same as that first Bohr's of hydrogen atom ?

The radius of which of the following orbit is same

The radius of the second Bohr orbit for hydrogen atom is (Planck's Const. h=6.6262xx10^(-34) Js, mass of electron = 9.1091xx10^(-31) kg , charge of electron e=1.60210xx10^(-19) C, permittivity of vacuum in_0=8.854185xx10^(-12) kg^(-1) m^(-3) A^2)

The radius of the second Bohr orbit for hydrogen atom is (Planck's constant, h = 6.6262 xx 10^(-34) Js mass of electron = 9.1091 xx 10^(-31) kg charge of electron, e = 1.60210 xx 10^(-19) C permitivity of the vacuum, in_(0) = 8.854185 xx 10^(-12) kg^(-1) m^(-3) A^(2))

The radius of the first orbit of hydrogen atom is 0.52 xx 10^(-8) cm. The radius of the first orbit of He^(+) ion is 0.26 xx 10^(-x)cm. Then the value of x is _______

The radius of the fourth orbit in hydrogen atom is 0.85 nm. Calculate the velocity of the electron in this orbit.

The radius of La^(3+) (Z=57) is 1.06A^(@). Which one of the following given values will be closest to the radius of Lu^(3+)

The radius of the first Bohr orbit of hydrogen atom is 0.59 Å. The radius of the third orbit of He^(+) will be

The radius of the atom is of the order of

The radius of nucleus is approximately times smaller than the radius of atom.

The radius of Na^(+) cation is less than that of Na atom. Give reason.

The radius of hydrogen atom in the ground state is 0.53 Å, the radius of Li^(2+) in the similar state is

The radius of first Bohr.s orbit for hydrogen is 0.53Å. The radius of third Bohr.s orbit would be

The radius of electron in the first excited state of hydrogen atom is

The radius of certain orbit of H-atom is 2.12 A. Then the energy of that energy level is

The radius of an Xeatom is 1.3 xx 10^(-8) cm A 100 cm^(3) container is filled with Xe at a pressure of 1.0 atm and a temperature of 273K Calculate the fraction of the volume that is occupied by Xe atoms .