94420 + Interview Questions in Chemistry in Class 12

1.	Equal volumes of 0.1 M urea and 0.1 M glucose are mixed. The mixture will have :
Answer» LOWER OSMOTIC pressure sameosmotic pressure higherosmotic pressure none of these Answer :B

Discussion

2.	Equal quantities of electricity of passed through three voltameters containing FeSO_(4) , Fe_(2) (SO_(4))_(3) and Fe(NO_(3))_(3) . Consider the following statements in this regard : 1 . The amount of iron deposited in FeSO_(4) and Fe_(2)(SO_(4))_(3) are equal 2 . The amount of iron deposited in Fe(NO_(3))_(3) is two third of the amount of iron deposited in FeSO_(4) 3 . The amount of iron deposited is Fe_(2)(SO_(4))_(3) and Fe(NO_(3))_(3) is equal
Answer» 1 alone is correct 1 and 2 are correct 2 and 3 are correct 3 alone is correct . SOLUTION :1. The O.S. of FE in `FeSO_(4)= + 2` and in `Fe_(2)(SO_(4))_(3) = + 3` 2 . The O.S. of Fe in `Fe(NO_(3))_(3) = + 3 ` and in `Fe(SO_(4)) = + 2` 3 . The O.S. of Fe in `Fe_(2)(SO_(4))_(3) = + 3` and in `Fe(NO_(3))_(3) = +3` Hence STATEMENT 2 and 3 are correct .

Discussion

3.	Equal quantities of electricity are passed through 3 votameters containing FeSO_(4),Fe_(2)(SO_(4))_(2) and Fe(NO_(3))_(3). Cosider the following statements (A) The amounts of iron deposited I FeSO_(4) and Fe_(2)(SO_(4))_(3) are equal (B) The amount of iron deposited in Fe(NO_(3))_(2) is 2//3^(rd) of the amount deposited in FeSO_(4) (C) The amount of iron deposited in Fe_(2)(SO_(4))_(3) and Fe(NO_(3))_(3) are equal
Answer» (A) is CORRECT (B) is correct (C) is correct Both (A) and (B) are correct Solution :Suppose 2F of ELECTRICITY passed through `FeSO_(4),Fe_(2)(SO_(4))_(3) and Fe(NO_(3))_(3)` solution. `FeSO_(4)toFe^(2+)+SO_(4)^(2-)` `Fe^(2+)+underset(2F)(2e^(-))tounderset("1 mole")(Fe(S))` `Fe_(2)(SO_(4))_(3)to2Fe^(3+)3SO_(4)^(2-)` `Fe^(3+)+underset(3F)(3e^(-))to underset(1" mole")(Fe(S))` `Fe(NO_(3))_(3)toFe_(3+)^(-)` `Fe^(3+)+underset(3F)(3e^(-))tounderset("1 mole")(Fe(S))` `therefore2F` will give`=(2)/(3)` mole

Discussion

4.	Equal quantities of electricity are passed through three voltametrs containing FeSO_(4),Fe_(2)(SO_4)_3 and Fe(NO_3)_3 Consider the following statements in this regard : The amount of iron deposited in FeSO_(4) and Fe_(2)(SO_4)_3 are equal 2. The amount of iron deposited in Fe(NO_3)_3 is two third of the amount of iron deposited in FeSO_4. 3 The amount of iron deposited in Fe_(2)(SO_4)_3 and Fe(NO_3) is equal . Which of the following statements is /are correct ?
Answer» only 1 1 and 2 2 and 3 Only 3 Solution :ASSUME 1 F CHARGE is PASSED through `FeSO_(4),Fe_(2)(SO_4)_3` and `Fe(NO_3)_3` `{:(" ",FeSO_4,Fe_2(SO_4)_3,Fe(NO_3)_3),("Amount of Fe deposited ", 56/2,56/3,56/3):}`

Discussion

5.	Equal quantities (50 ml) of the following four samples of water are placed in four beakers of 100 ml capacity . Their boiling points are determined accurately using the same thermometer . Which sample of water will having the lowermost boiling point as compared to other three samples ?
Answer» DISTILLED water Bottled mineral water Well water Seawater SOLUTION :Distilled water

Discussion

6.	Equal number of moles of A and B are allowed to react with each other till it reaches equilibrium. 2A+BhArrC+D The value of K_(c) for this equilibrium can never be
Answer» `GT1` `LT1` `=1` `OO` Answer :C::D

Discussion

7.	Equal molecules of N_2 and O_2 are kept in a closed container at pressure P. If N_2 is removed from the system, then the pressure of the container will be
Answer» <P>P P//2 `P/4` 2P Answer :B

Discussion

8.	Equal masses of oxygen hydrogen and methane are taken in a container under identical conditions. Find the ratio of their volumes.
Answer» ANSWER :`1:16:2`

Discussion

9.	Equal masses of nitrogen and ethyleneare mixed in an empty container at 27^@ C. The total pressure exerted by the gaseous mixture is 1 atm. The partial pressure exerted by ethylene gas is :
Answer» 0.67 atm 0.33 atm 0.50 atm 0.20 atm Answer :C

Discussion

10.	Equal masses of KClO_(3) undergoes different reaction in two different container: (i) 2KClO_(3) to 2KCl + 3O_(2) (ii) 4KClO_(3)to KCl + 3KClO_(4) Mass ratio of the KCl produced in respective reaction is x : 1. Value of 'x' will be
Answer» 4 2 0.25 3 Answer :A

Discussion

11.	Equal masses of methane and oxygen are mixed in an empty container at 25^(@)C. The fraction of total pressure exerted by oxygen is
Answer» `(1)/( 3) XX ( 273)/( 298) ` `(1)/( 3)` `(1)/(2)` `(2)/(3)` Solution :Let the mass of METHANE and oxygen be x g each. Moles of `CH_(4) = ( x )/( 16)` Moles of `O_(2) = ( x )/( 32)` TOTAL moles `= ( x )/( 16) + ( x)/( 32) = ( 3x )/( 32)` `p_(O_(2)) = p_("total")xx x_(O_(2))` `( p_(O_(2)))/( p_("total")) = x_(2)= ((x)/( 32))/( (3x)/(32)) = ( 1)/( 3)`

Discussion

12.	Equal masses of a solute are dissolved in equal amount of two solvents A and B respective molecular masses being M_(A) and M_(B) . The relative lowering of vapour pressure of solution in solvent A is twice that of the solution in solvent B. If the solutions are dilute , M_(A) and M_(B) are related as
Answer» `M_(A)=M_(B)` `2M_(A)=M_(B)` `M_(A)=2M` `M_(A)=4M_(B)` ANSWER :C

Discussion

13.	Equal mass of oxygen and helium gases are mixed in a container at 27°C Fraction of total pressure exerted by helium gas is
Answer» `1/8` `8/9` `1/4` `3/4` ANSWER :2

Discussion

14.	Equal amounts of two gases of molecular weight 4 and 40 are mixed. The pressure of the mixture is 1.1 atm. The partial pressure of the light gas in this mixture is
Answer» <P>0.55 atm 0.11 atm 1 atm 0.12 atm Solution :No. of moles of lighter gas `= (m)/(4)` No. of moles of heavier gas `=(m)/(40)` Total no. of moles of `(m)/(4)+(m)/(40)=(11M)/(40)` Mole fraction of lighter gas `((m)/(4))/((11m)/(40))=(10)/(11)` Partial PRESSURE due to lighter gas `=P_(o)xx(10)/(11)=1.1 xx (10)/(11) =1 `atm.

Discussion

15.	Equal amounts in grams of following sub-stances were dissolved in equal amount of water. Which of these will have the highest boiling point ?
Answer» Urea `(NH_(2) CONH_(2))` Glucose `(C_(6)H_(12)O_(6))` Sodium chloride ( NaCl ) Calcium chloride `(CaCl_(2))` Solution :The simple inspection of the question shows that (C) should be the correct choice because `CaCl_(2)` will give 3 mol of ions for 1 mol of `CaCl_(2)` DISSOLVED (assuming it to be completely dissociated). However, in the given question, the amounts are given in GRAMS. If we assume, `w` gram of all thesubstances are dissolved in 1000 g of solvent, then Molal conc. of NaCl `=(w)/(58.5)m` Molar conc. of `CaCl_(2)=(w)/(111)` m Since NaCl gives two mole of ions for one mole of it so that Molar concentration of ions in solution `=(w)/(58.5)xx2=0.034w` `CaCl_(2)` gives three moles of ions for 1 mol of it so that Molar conc. of ions in solution `=(w)/(111)xx3=0.027 w` Therefore, molal conc. of solute in NaCl solution is more than in `CaCl_(2)` solution.

Discussion

16.	Equal amounts of two samples of carbon were burnt and the radioactivities ofCO_2 formed were measured. The activitied were 2100and 1400 counts per week respectively.What will be the age difference of the sample. [ t_(1//2) forC^(14) = 5600 years ]
Answer» 2002 years 2345 years 4250 years 3343 years Solution :`t_(1//2) = 5600` years Decay constant , `LAMBDA = (0.693)/(t_(1//2)) = (0.693)/(5600) = 1.24 xx 10^(-4) "year"^(-1)` For first sample : `(N_0)/(N) = ("NUMBER of counts per week of CARBON INITIALLY")/("number of counts per week of carbon finally")` `= (N_0)/(2100) "".......(i)` For second sample : `(N_0)/(N) = (N_0)/(1400) "" .......(ii)` The AGE difference of the sample : `t = (2.303)/(lambda) ["log" (N_0)/(1400) - "log" (N_0)/(2100)]` `= (2.303)/(1.24 xx 10^(-4))["log" N_0 - "log" 1400 - "log" N_0 + log 2100]` `= (2.303)/(1.24 xx 10^(-4)) [log 2100 - log 1400]` `= (2.303)/(1.24 xx 10^(-4)) [3.32 - 3.14]` `= t = (2.303)/(1.24 xx 10^(-4)) xx 0.18 = 3343.06` years

Discussion

17.	Equal amount of aqueous solution of CuSO_4 and alkaline sodium potassium tartarate is mixed and treated with aliphatic aldehyde, then
Answer» RED BROWN PPT of `Cu_2O` is formed Red brown ppt of CUO is formed Blue ppt of CuO is formed There will be no reaction Answer :A

Discussion

18.	Eq. wt. of an acid salt NaHSO_(4) is
Answer» M/2 M/3 M/1 None Answer :C

Discussion

19.	Eq. wt of a metal , x g of which reacts with 1 eq. of an acid is
Answer» 1 x/2 2x x Answer :d

Discussion

20.	Epsom salt or epsomite ore is:
Answer» `MgSO_4.7H_2O` `MgSO_4.2h_2O` `MgSO_4.H_2O` `CaSO_4.2H_2O` ANSWER :A

Discussion

21.	Epsom salt is MgSO_(4) H_(2)O What is the value of x' in epsom salt
Answer» SOLUTION :Epsomsalt is `MgSO_(4).7H_(2)O`. The value of .X. is 7.

Discussion

22.	Epsom salt has the following uses except :
Answer» as a puragative in medicines in dyeing and tanning industries as a food preservative a catalyst in the MANUFACTURE of SULPHURIC acid. Answer :C

Discussion

23.	Epoxy resins use a polymer made from bisphenol A and epichlorohydrin in basic medium. Which of the Statement are incorrect.
Answer» REACTION proceeds VIA `SN_(2)` The nucleophile attacks from hindered side. Chirality of carbon in epichlorihidrin is retained in each step two `SN_(2)` REACTIONS take place. Answer :B

Discussion

24.	Eplain why the stability of oxaacids of chlorine increasesin theorder given below ? HClO lt HClO_(2) lt HClO_(3) lt HClO_(4)
Answer» Solution :(i) All these acids on losing a PROTON give their correspondingconjugate BASES (ie) `ClO^(-), ClO_(2)^(-), ClO_(3)^(-)` and `ClO_(4)^(-)`. Their structures are: (ii) Since, oxygen is more electronegative than chlorine, therefore dispersalof negative CHARGE present on oxygen atom (singly bonded to Cl) increases as the number of oxygen atoms attached by a double bond to chlorine increases due to `P pi - d pi` back bonding. (iii) Therefore stability of IONS will increasein the following order: `ClO- LT ClO_(2)- lt ClO_(3)= lt ClO_(4)-` (iv) Due to increase instability of conjugate base, acidic strength of correspondingacid increases in thesame order as : `HClO- lt HClO_(2) lt HClO_(3) lt HClO_(4)`

Discussion

25.	Epimers are pair of diastereoisomeric aldoses which differ only in configuration at position :
Answer» `C_5` `C_2` `C_4` `C_3` ANSWER :B

Discussion

26.	Epilepsy is caused due to deficiency of………………..
Answer» VITAMIN `B_(6)` Vitamin `B_(12)` Vitamin E Vitamin K SOLUTION :Vitamin `B_(6)`

Discussion

27.	E^(o) value of Mg^(2+)\|Mg,Fe^(2+)\|Fe and Zn^(2+) \| Zn" are " - 2.37 V, - 0.44 and - 0.76 V respectively. The correct statement is :
Answer» MG oxidizes Fe Zn oxidizes. Fe Zn REDUCES Mg Zn reduces `Fe^(2+)` ANSWER :D

Discussion

28.	E^(o) for the cell Zn\|Zn_((aq))^(2+)\|\|Cu_((aq))^(2+)\|Cu is 1.10 V at 25^(@)C, the equilibrium constant for the reaction Zn+Cu_((aq))^(2+)hArrCu+Zn_((aq))^(2+) is of the order of
Answer» `10^(-28)` `10^(-37)` `10^(+18)` `10^(+17)` Solution :`E_(cell)^(@)=(0.059)/(N)log" "K` `log" "K=(1.10xx2)/(0.059)=37.2881` or `K=10^(-37)`

Discussion

29.	Enzymes work best under ordinary conditions of temperature and pH
Answer»

Discussion

30.	Enzymes trypsin converts
Answer» Proteins into `alpha`-AMINO ACIDS Starches into sugar Glucose into glycogen `alpha`-amino acids into proteins Answer :A

Discussion

31.	Enzymes, in the living systems:
Answer» PROVIDE energy Provide immunity Transport oxygen Catalysed BIOCHEMICAL process Answer :D

Discussion

32.	Enzymes in the living systems :
Answer» provide energy transport OXYGEN CATALYSE biochemical REACTIONS provide immunity. SOLUTION :Enzymes in living systems catalyse biochemical reactions.

Discussion

33.	Enzymes in the living systems…….. .
Answer» PROVIDE energy provideimmunity CATALYSE BIOLOGICAL TRANSPORT oxygen Answer :C

Discussion

34.	Enzymes in the living system
Answer» Provide energy Provide IMMUNITY Transport OXYGEN Catalyse biological PROCESS ANSWER :D

Discussion

35.	Enzymes greatly reduce the amount of ____________in their action.
Answer» SOLUTION :ACTIVATION ENERGY

Discussion

36.	Enzymes can be active in human body at a temperature of ............
Answer» `98^(@)F` `105^(@)F` `37^(@)F` `50^(@)F` SOLUTION :`98^(@)F`

Discussion

37.	Enzymes belong to which class of compounds ?
Answer» Polysaccharides Polypeptides Polynitro HETEROCYCLIC compounds Hydrocarbons ANSWER :B

Discussion

38.	Enzymes belong to a category of :
Answer» PROTEINS CARBOHYDRATES VITAMINS harmones Answer :A

Discussion

39.	Enzymes are made up of ?
Answer» PROTEIN Lipid Vitamin Carbohydrate Answer :A

Discussion

40.	Enzymes are made up of .......
Answer» Carbohydrate Lipid PROTEIN Sucrose SOLUTION :Protein

Discussion

41.	Enzymes are made of ………………..
Answer» PROTEINS VITAMIN LIPID Carbohydrate Solution :Proteins

Discussion

42.	Enzymes are made up of
Answer» Edible proteins Proteins with SPECIFIC structure Nitrogen CONTAINING carbohydrates Carbohydrates Answer :B

Discussion

43.	Enzymes are known to increase the rate of reaction by :
Answer» `10^2` TIMES `10^-2` times `10^5` times `10^12` times Answer :D

Discussion

44.	Enzymes are known as biochemical catalysis. Write the two important characteristics of enzyme catalysis.
Answer» Answer :Enzymes are highly specific in nature, i.e., one enzyme cannot CATALYSE more than one reaction. Highly ACTIVE at OPTIMUM temperature (298-310K) and optimum pH (between 5 and 7).

Discussion

45.	Enzymes are basically
Answer» EDIBLE proteins Carbohydrates Carbodydrates CONTAINING nitrogen Specially stuctured proteins Answer :D

Discussion

46.	Enzymes are :
Answer» LIVING organisms Dead organisms Complex NITROGENOUS SUBSTANCES PRODUCED from living cells None Answer :C

Discussion

47.	Enzymes :
Answer» Have OPTIMUM ACTIVITY at BODY temperature Consists of NUCLEIC acids Carbohydrates Have all these PROPERTIES Answer :A

Discussion

48.	Enzymes are
Answer» COMPLEX nitrogenous substances produced in living CELLS Steroids Living organisms Dead organisms ANSWER :A

Discussion

49.	Enzyme which breaks down starch to maltose is
Answer» MALTASE zymase diastase Glucose SOLUTION :Maltase.

Discussion

50.	Enzyme trypsin converts
Answer» STARCH into sugar proteins into `alpha`-AMINO ACIDS glucose into glycogen `alpha`- amino acids into proteins Solution :Protein `OVERSET"Trypsin"to alpha`-amino ACID

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Equal volumes of 0.1 M urea and 0.1 M glucose are mixed. The mixture will have :

Equal quantities (50 ml) of the following four samples of water are placed in four beakers of 100 ml capacity . Their boiling points are determined accurately using the same thermometer . Which sample of water will having the lowermost boiling point as compared to other three samples ?

Equal number of moles of A and B are allowed to react with each other till it reaches equilibrium. 2A+BhArrC+D The value of K_(c) for this equilibrium can never be

Equal molecules of N_2 and O_2 are kept in a closed container at pressure P. If N_2 is removed from the system, then the pressure of the container will be

Equal masses of oxygen hydrogen and methane are taken in a container under identical conditions. Find the ratio of their volumes.

Equal masses of nitrogen and ethyleneare mixed in an empty container at 27^@ C. The total pressure exerted by the gaseous mixture is 1 atm. The partial pressure exerted by ethylene gas is :

Equal masses of KClO_(3) undergoes different reaction in two different container: (i) 2KClO_(3) to 2KCl + 3O_(2) (ii) 4KClO_(3)to KCl + 3KClO_(4) Mass ratio of the KCl produced in respective reaction is x : 1. Value of 'x' will be

Equal masses of methane and oxygen are mixed in an empty container at 25^(@)C. The fraction of total pressure exerted by oxygen is

Equal mass of oxygen and helium gases are mixed in a container at 27°C Fraction of total pressure exerted by helium gas is

Equal amounts of two gases of molecular weight 4 and 40 are mixed. The pressure of the mixture is 1.1 atm. The partial pressure of the light gas in this mixture is

Equal amounts in grams of following sub-stances were dissolved in equal amount of water. Which of these will have the highest boiling point ?

Equal amounts of two samples of carbon were burnt and the radioactivities ofCO_2 formed were measured. The activitied were 2100and 1400 counts per week respectively.What will be the age difference of the sample. [ t_(1//2) forC^(14) = 5600 years ]

Equal amount of aqueous solution of CuSO_4 and alkaline sodium potassium tartarate is mixed and treated with aliphatic aldehyde, then

Eq. wt. of an acid salt NaHSO_(4) is

Eq. wt of a metal , x g of which reacts with 1 eq. of an acid is

Epsom salt or epsomite ore is:

Epsom salt is MgSO_(4) H_(2)O What is the value of x' in epsom salt

Epsom salt has the following uses except :

Epoxy resins use a polymer made from bisphenol A and epichlorohydrin in basic medium. Which of the Statement are incorrect.

Eplain why the stability of oxaacids of chlorine increasesin theorder given below ? HClO lt HClO_(2) lt HClO_(3) lt HClO_(4)

Epimers are pair of diastereoisomeric aldoses which differ only in configuration at position :

Epilepsy is caused due to deficiency of………………..

E^(o) value of Mg^(2+)|Mg,Fe^(2+)|Fe and Zn^(2+) | Zn" are " - 2.37 V, - 0.44 and - 0.76 V respectively. The correct statement is :

E^(o) for the cell Zn|Zn_((aq))^(2+)||Cu_((aq))^(2+)|Cu is 1.10 V at 25^(@)C, the equilibrium constant for the reaction Zn+Cu_((aq))^(2+)hArrCu+Zn_((aq))^(2+) is of the order of

Enzymes work best under ordinary conditions of temperature and pH

Enzymes trypsin converts

Enzymes, in the living systems:

Enzymes in the living systems :

Enzymes in the living systems…….. .

Enzymes in the living system

Enzymes greatly reduce the amount of ____________in their action.

Enzymes can be active in human body at a temperature of ............

Enzymes belong to which class of compounds ?

Enzymes belong to a category of :

Enzymes are made up of ?

Enzymes are made up of .......

Enzymes are made of ………………..

Enzymes are made up of

Enzymes are known to increase the rate of reaction by :

Enzymes are known as biochemical catalysis. Write the two important characteristics of enzyme catalysis.

Enzymes are basically

Enzymes are :

Enzymes :

Enzymes are

Enzyme which breaks down starch to maltose is

Enzyme trypsin converts