94420 + Interview Questions in Chemistry in Class 12

1.	Assertion (A) : Transparent soaps are made by dissolving soaps in ethanol. Reason (R) : Ethanol makes things invisible.
Answer» ASSERTION and reason both are CORRECT statement but reason does not explain assertion. Assertion and reason both are correct and reason explains the assertion. Both assertion and reason are wrong statement. Assertion is correct statement reason is wrong statement. Solution :Assertion is correct statement reason is wrong statement. Correct reason : Ethanol removes air and moisture which scatter LIGHT.

Discussion

2.	Assertion (A) Transparent soaps are made by dissolving soaps in ethanol. Reason (R) Ethanol makes things invisible.
Answer» If both ASSERTION and reason are trueand reason is the correct explanationof assertion . If both assertion and reason are true but reason is not the correct explanationof assertion . If assertion is true but reason is FALSE. If both assertion and reason are false. Solution :ETHANOL removes air and MOISTURE which SCATTER light.

Discussion

3.	Assertion (A) : Transition metals vary widly in their chemical activity. Reason (R) : Many of transition elements are sufficiently electropositive to dissolve in mineral acids.
Answer» Both Assertion (A) and REASON (R) are correct statements, and Reason (R) is the correct explanation of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect STATEMENT. Assertion (A) is incorrect, but Reason (R) is correct statement. ANSWER :B

Discussion

4.	Assertion (A): Transition metals form large number of complexes. Reason (R): Transition metals are small and highly charged and they have vacant low energy orbitals to accept an electron pair donated by other groups,
Answer» Both (A) and (R) are CORRECT and (R) EXPLAINS (A). Both (A) and (R) are correct but (R) is not the correct EXPLANATION of (A). (A) is correct but (R) is WRONG. (A) is wrong but (R) is correct. Solution :Both (A) and (R) are correct and (R) explains (A).

Discussion

5.	Assertion (A) : Transition metals have low melting points. Reason (R ) : The involvement of greater number of (n - 1)d and ns electrons in the interatomic metallic bonding.
Answer» Both Assertion (A) and Reason (R) are CORRECT statements, and Reason (R) is the correct explanation of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R) is INCORRECT statement. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :D

Discussion

6.	Assertion ( A) : Total number of octahedral voids present in unit cell of cubic close packing including the one that is present at the body centre is four. Reason ( R ) : Besides the body centre there is one octahedral void present at the centre of each of the six faced of the unit cell and each of which is shared between the adjacent unit cells.
Answer» Both assertion and reason are TRUE and reason is the CORRECT explanation of assertion. Both assertion and reason are true but reason is not the correct explanation of assertion. Assertion is true but reason is false Both assertion and reason are false. Answer :C

Discussion

7.	Assertion (A) : The vapour pressure of a solution containing non-volatile solute is less thanthe vapour pressure of pure solvent.Reason (R) : In the case of a solution of a non-volatile solute, some of the surface positionsare occupied by the solute.
Answer» Both Assertion (A) and REASON (R) are CORRECT statements, and Reason (R) is the correct EXPLANATIONOF the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanationof the Assertion (A). Assertion (A) is correct, but Reason (R) is INCORRECT statement, Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :A

Discussion

8.	Assertion (A) : The vapour phase is always richer in the component which is less volatile.Reason (R) : The relative lowering of the vapour pressure of a solution is proportional tomole fraction of the solvent.
Answer» Both ASSERTION (A) and Reason (R) are correct STATEMENTS, and Reason (R) is the correct explanationof the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanationof the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect statement, Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :D

Discussion

9.	Assertion (A) : The weak polarity of ethers does not appreciably affect their boiling points which are comparable to those of alkanes of comparable molecular masses. Reason (R) :Miscibility of ethers with water resembles that of alcohols of the same molecular mass.
Answer» Both ASSERTION (A) and REASON (R) are CORRECT statements, and Reason (R) is the correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct EXPLANATIONOF the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect statement. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :B

Discussion

10.	Assertion (A) : The values of the rate-constants of simple and complex molecules, determined with the help of Arrhenius equation, are all correct. Reason (R) : A chemical change does not depend on the orientation of the molecules at the moment of a collision.
Answer» (A) and (R) both are correct STATEMENTS and (R) is correct explanation for (A). (A) and (R) both are correct statements and (R) isnot correct explanation for (A). (A) is correct STATEMENT but (R) is WRONG statement. (A) is wrong statement but (R) is correct statement . Answer :C

Discussion

11.	Assertion (A) : The value of van't Hoff factor denotes the extent of association and dissociationof the solute.Reason (R) : Osmotic pressure is given by the relation pi = (CR)/(T)
Answer» Both Assertion (A) and Reason (R) are CORRECT statements, and Reason (R) is the correct explanationof the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanationof the Assertion (A). Assertion (A) is correct, but Reason (R) is INCORRECT statement, Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :C

Discussion

12.	Assertion (A) :The two strands in double strand helix structure ofo DNA are complementary to each other Reaso (R ) : Disulphide bonds are formed between specific pairs of bases.
Answer» Both Assertion (a) And Reason (R )are CORRECT Statement . And Reason (R )is the correct EXPLANATION of the Assertion (A) Both Assertion (A) and Reason (R ) are correct statement , bbut Reason (R ) is not the correct expanation of the Assertion (A) Assertion (A) is correct , but Reason (R ) is correct statement . Assertion (A ) is incorrect but Reason (R ) Is correct statement. ANSWER :C

Discussion

13.	Assertion (A) : The total pressure over the solution in a container is equal to the sum of partialpressure of the components.Reason (R) : The melting point of solution is lowered on addition of a non-volatile soluteinto it.
Answer» Both Assertion (A) and REASON (R) are CORRECT statements, and Reason (R) is the correct EXPLANATIONOF the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanationof the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect STATEMENT, Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :B

Discussion

14.	Assertion (A): The stability of -2 oxidisation state in Group 16 decreases down the Group. Reason (R) : The anomalous behaviour of oxygen is due to its large size and low electronegativity.
Answer» Both Assertion (A) and Reason (R) are CORRECT statements, and Reason (R) is the correct EXPLANATION of the Assertion (A) Both Assertion (A) and Renson (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A) Assertion (A) is correct, but Reason (R) is incorrect statement. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :C

Discussion

15.	Assertion (A) : The representation of rate of reaction I n terms of concentration of the reactants is known as rate law: Reason (R ) : Order of the reaction: CHCl_(3)+Cl_(2) to C Cl_(4)+HClis (3)/(2).
Answer» Both Assertion (A) and REASON (R ) are CORRECT statements, and Reason (R ) is the correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R ) are correct statements, but Reason (R ) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R ) is INCORRECT statement. Assertion (A) is incorrect, but Reason (R ) is correct statement. Answer :B

Discussion

16.	Assertion (A): The stereoisomer's related to each other as non-super imposable mirror images are called enantiomers. Reason (R) : Butan-2-ol has four different groups attached to the tetrahedral carbon and is chiral.
Answer» Both ASSERTION (A) and Resort (R) are correct statements, quid Reason (R) is the correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, brit Reason (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect statement. Assertion (A) is incorrect, but Renson (R) is correct statement. Answer :b

Discussion

17.	Assertion (A) : The rate of a reaction increases with the increase in the concentration of the reactants . Reason (R) : The rate of the reaction depends upon the number of Collisions between the reacting molecules. Higher the concentration , greater is the possibility for collision and hence the rate .
Answer» Both A and R are CORRECT and R is the correct EXPLANATION of A Both A and R are correct but R is not the correct explanation of A A is correct but R is WRONG A is wrong but R is correct ANSWER :a

Discussion

18.	Assertion (A): The process of removing a dissolved substance from a colloidal solution by means of diffusion through a membrane is called dialysis. Reason (R) : Tyndall effect is observed due to the fact that colloidal particles scatter light in all directions in space.
Answer» Both Assertion (A) and REASON (R) are CORRECT statements, and Reason (R) is the correct explanation of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A) Assertion (A) is correct, but Reason (R) is INCORRECT STATEMENT. Assertion (A) is incorrect, but Reason (R) is correct statement Answer :B

Discussion

19.	Assertion (A): The process of formation of polymers from respective monomers is called polymerisation. Reason (R) : Polymers have large molecular masses in the range of 10^(3)-10^(7) u.
Answer» Both Assertion (A) and Reason (R) are correct STATEMENTS, and Rerson (R) is the correct EXPLANATION of the Assertion (A) Both Assertion (A) and RESON (R) are correct statements, but Reson (R) is not the correct explanation of the Assertion (A) Assertion (A) is correct, but Reason (R) is incorrect statement. Assertion (A) is incorrect, but Reason (R) is correct statement. ANSWER :B

Discussion

20.	Assertion (A) : The primary valencies are ionizable and are satisfied by positive ions. Reason (R) : Central atoms/ions in coordination compounds are also referred to as Lewis acids.
Answer» Both ASSERTION (A) and REASON (R) are correct statements, and Reason (R) is the correct EXPLATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explation of the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect statement. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :D

Discussion

21.	Assertion (A): The presence of nitro group facitatesnucleophilicsubstiution reaction in aryl halide. Reason (R):The intermdiate carbonion is stablised due to the presence of the nitro group.
Answer» Both `(A)` and `(R)` are true and `(R0` is the correct explanation of `(A)`. Both `(A)` and `(R)` are true but `(R)` is not the correct explanation of `(A)`. `(A) is true but `(R)` is false. `(A) is falsebut `(R)` is true. Solution :NA

Discussion

22.	Assertion (A) : The overall decrease in atomic and ionic radii from lanthanum to lutetium is called lanthanoide contraction. Reason (R) : Permanganate titrations can be carried out in the presence of any mineral acid.
Answer» Both Assertion (A) and REASON (R) are CORRECT statements, and Reason (R) is the correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect STATEMENT. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :C

Discussion

23.	Assertion (A) : The outer sphere in the complex compound is called ionisation sphere. Reason (R ) : The groups present in outer sphere are loosely bound to the central metal ion and hence can be separated into ions upon dissolving the complex in the suitable solvent.
Answer» Both A and R are CORRECT and R is the correct EXPLANATION of A. Both A and R are correct but R is not the correct explanation of A. A is correct but R is WRONG A is wrong but R is correct Answer :A

Discussion

24.	Assertion (A) : The nucleus of gold is stable even though there is a very strong coulombic repulsion among the protons. Reason (R) :The inverse square coulomb force is exactly balanced by another inverse square force which is very powerful. i.e.,nuclear force.
Answer» If both `(A)` and `(R)` are CORRECT , and `(R)` is the correct EXPLANATION of `(A)` If both `(A)` and `(R)` are correct, but (R) is not the correct explanation of `(A)` If `(A)` is correct, but `(R)` is INCORRECT. If `(A)` is incorrect, but `(R)` is correct. Answer :C

Discussion

25.	Assertion (A) : The molecularity of the reaction H_(2)+Br_(2) to 2HBr appears to be 2. Reason (R ) : Two molecules of the reactants are involved in the given elementary reaction.
Answer» Both ASSERTION (A) and Reason (R ) are CORRECT statements, and Reason (R ) is the correct explanation of the Assertion (A). Both Assertion (A) and Reason (R ) are correct statements, but Reason (R ) is not the correct explanation of the ASSERITON (A). Assertion (A) is correct, but Reason (R ) is incorrect STATEMENT. Assertion (A) is incorrect, but Reason (R ) is correct statement. Answer :A

Discussion

26.	Assertion (A): The molecular mass of polymers can be determined by chemical and physical methods. Reason (R) PHBV does not undergo bacterial degradation in the environment.
Answer» Both Assertion (A) and Reason (R) are correct statements, and Rerson (R) is the correct explanation of the Assertion (A) Both Assertion (A) and RESON (R) are correct statements, but Reson (R) is not the correct explanation of the Assertion (A) Assertion (A) is correct, but Reason (R) is INCORRECT STATEMENT. Assertion (A) is incorrect, but Reason (R) is correct statement. ANSWER :C

Discussion

27.	Assertion (A): The mathematical equation of Freondlich isotherm islog""(x)/(m)=log k -(1)/(n) log p Reason (R) : Oxygen is adsorbed on metals by virtue of oxide formation.
Answer» Both Assertion (A) and REASON (R) are correct statements, and Reason (R) is the correct explanation of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A) Assertion (A) is correct, but Reason (R) is INCORRECT STATEMENT. Assertion (A) is incorrect, but Reason (R) is correct statement ANSWER :D

Discussion

28.	Assertion (A): The minor product obtained in the reaction between CH_(3) CH = CH_(2) " and " HI " is " CH_(3)CH_(2)CH_(2) I. . Reason (R) : Alkyl bromides and iodides develop colour when exposed to light.
Answer» Both Assertion (A) and Resort (R) are correct STATEMENTS, quid REASON (R) is the correct explanation of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, brit Reason (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect STATEMENT. Assertion (A) is incorrect, but RENSON (R) is correct statement. Answer :b

Discussion

29.	Assertion (A): The manufacture of sulphuric acid by contact process is an example of heterogeneous catalysis. Reason (R) : The catalyst Pt (or) V_(2)O_(5)reactants and products are in different phases in contact process.
Answer» Both A and R are CORRECT and R is the correct EXPLANATION of A. Both A and R are correct but R is not correct explanation of A. Both A and R are WRONG. A is wrong but R is correct. ANSWER :A

Discussion

30.	Assertion (A): The large difference between the melting and boiling points of oxygen and sulphur may be explained on the basis of their atomicity. Reason (R) : Oxygen gas can be obtained by heating salts such as chlorates, nitrates and permanganates.
Answer» Both ASSERTION (A) and REASON (R) are CORRECT statements, and Reason (R) is the correct explanation of the Assertion (A) Both Assertion (A) and Renson (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A) Assertion (A) is correct, but Reason (R) is INCORRECT statement. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :B

Discussion

31.	Assertion (A) : The IUPAC name of benzaldehyde is benzene carbaldehyde. Reason (R) : The carbon-oxygen double bond is polarised due to higher electronegativity of carbon relative to oxygen.
Answer» Both ASSERTION (A) and Reason (R) are CORRECT statements, and Reason (R) is the correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect STATEMENT. Assertion (A) is incorrect, but Reason (R) is correct statement Answer :C

Discussion

32.	Assertion (A): The highest oxidation state of osmium is (+8). Reason (R ): Osmium is a 5d-block elements
Answer» Both ASSERTION and reason are true and reason is the correct explanation of the assertion Both assertion and reason are true, but reason is not correct explanation of the assertion Assertion is not true reason is true Both assertion and reason are false Solution :(+8) oxidation state of osmiumis due to its ABILITY to use all its EIGHT electrons.

Discussion

33.	Assertion (A) : The hydrogen attached to nitrogen in sulphonamide is strongly acidic. Reason (R) : Benzene sulphonyl chloride is also known as Hinsberg's reagent.
Answer» Both Assertion (A) and Reason (R) are correct STATEMENTS, and Reason (R) is the correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R) is INCORRECT statement. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :B

Discussion

34.	Assertion (A): The following reaction occurs. Reason (R ): The product is a stable cylic hemiacetal formed by the anion of (A) product of centre is formed, thus (B) is racemate.
Answer» Both (A) and (R ) TRUE and (R ) is the CORRECT EXPLANATION of (A). Both (A) and (R ) are true but (R ) is not correct explanation of (A). (A) is true but (R ) is FALSE. (A) is false but (R ) is true. Answer :A

Discussion

35.	Assertion (A) : The extent to which a reaction will proceed can be determined from chemical equilibrium. Reason (R ) : The word kinetics is derived from the Greekword kinesis.
Answer» Both Assertion (A) and Reason (R ) are correct STATEMENTS, and Reason (R ) is the correct explanation of the Assertion (A). Both Assertion (A) and Reason (R ) are correct statements, but Reason (R ) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R ) is incorrect STATEMENT. Assertion (A) is incorrect, but Reason (R ) is correct statement. Answer :B

Discussion

36.	Assertion (A) : The enthalpy of a reaction does not change in the presence of a catalyst.Reason (R) : A catalyst takes part in the reaction, forms an activated complex and reduces the activation energy. However, the energy difference between the reactants and the products remain the same.
Answer» (A) and (R) both are CORRECT STATEMENTS and (R) is correct explanation for (A). (A) and (R) both are correct statements and (R) ISNOT correct explanation for (A). (A) is correct statement but (R) is WRONG statement. (A) is wrong statement but (R) is correct statement . Answer :A

Discussion

37.	Assertion (A) : The empirical mass of ethene is half of its molecular mass. Reason (R) : The empirical formula represents the simplest whole number ratio of various atoms present in a compoud.
Answer» Both A and R TRUE and R is the CORRECT EXPLANATION of A. A is true but R is FALSE. A is false but R is true. Both A and R are false. Solution :Both A and R true and R is the correct explanation of A.

Discussion

38.	Assertion (A) : The elements which give the greatest number of oxidation states occur in or near the middle of the series. Reason (R) : The lowest common oxidation state of transition elements is +2.
Answer» Both Assertion (A) and REASON (R) are correct statements, and Reason (R) is the correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect STATEMENT. Assertion (A) is incorrect, but Reason (R) is correct statement. ANSWER :B

Discussion

39.	Assertion (A): The conversion of fresh precipiate to colloidal state is called peptization Reason ( R) : It is caused by addition of commonions
Answer» Both (A) and ( R) are true and ( R) is the CORRECT EXPLANATION of ( A) Both ( A) and (R ) true but ( R) is not the correct explanation of ( A) (A) is true but ( R) is FALSE (A) is false but ( R) is true Answer :B

Discussion

40.	Assertion (A): The compounds in which the halogen atom is bounded to an sp^(3) hybridised carbon atom adjacent to the carbon-carbon double bond are called vinylic halides. Reason (R) : Common names of alkyl halides are derived by naming the alkyl group folllowed by the name of the halide.
Answer» Both Assertion (A) and Resort (R) are CORRECT statements, quid REASON (R) is the correct explanation of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, brit Reason (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason (R) is INCORRECT statement. Assertion (A) is incorrect, but RENSON (R) is correct statement. Answer :d

Discussion

41.	Assertion (A) : The cell potential of mercury cell is 1.35 V which remains constant. Reason (R): In mercury cell, the electrolyte is a paste of KOH and ZnO.
Answer» Both A and R are CORRECT, but R is not the correct EXPLANATION of A. Both A and R are correct, but R is the correct explanation of A. A is WRONG but R is correct A is correct but R is wrong ANSWER :A

Discussion

42.	Assertion (A) : The cell potential of mercury cell is 1.35 V which remains constant. Reason (R ) : In mercury cell, the electrolyte is a paste of KOH and ZnO.
Answer» Both A and R are CORRECT, but R is not the correct EXPLANATION of A Both A and R are correct, but R is the correct explanation of A A is WRONG but R is correct A is correct but R is wrong ANSWER :A

Discussion

43.	Assertion (A) : The catalyst used inFriedel Crafts reaction is anhydrous AlCl_(3). Reason (R) : Anhydrous aluminium chloride is a Lewis acid.
Answer» Both ASSERTION (A) and Reason (R) are CORRECT statements, and Reason (R) is the correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanationof the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect statement. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :A

Discussion

44.	Assertion (A) : The C - O - H bond angle in alcohols in slightly less than the tetrahedral angle. Reason ( R ) : This is due to the repulsive interaction between the two lone electron pairs on oxygen.
Answer» Both Assertion (A) and REASON ( R ) are CORRECT statements, and Reason ( R ) is the correct explanation of the Assertion (A). Both Assertion (A) and Reason ( R ) are correct statements, but Reason ( R ) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Reason ( R ) is incorrect STATEMENT. Assertion (A) is incorrect, but Reason ( R ) is correct statement. ANSWER :A

Discussion

45.	Assertion (A): The C-O-C bond angle in eithers is slightly less than tetrahedral angle. Reason (R ): Due to the repulsive interaction between the two alkyl groups in ethers.
Answer» Both ASSERTION (A) and REASON (R ) are CORRECT statements, and Reason ( R) is the correct explanation of the Assertion (A) Both Assertion (A ) and Reason ( R) are correct statements, but Reason ( R) is not the correct explanation of the Assertion (A) Assertion (A) is correct, but Reason (R ) is incorrect statement Assertion (A) is incorrect, but Reason (R ) is correct statement. Answer :C

Discussion

46.	Assertion (A): The C-N-C bond angle of trimethyl amine is 108^(@). Reason(R):The bond of C-N -C is due to the repulsion between the bulky methyl groups.
Answer» Both A and R are CORRECT and r is EXPLAINS A Both A and R but R is wrong A is correct but R is wrong A is wrong but R is correct Answer :C

Discussion

47.	Assertion (A) : The boiling points of alkyl halides decrease in the order : RI gt RBr gt RCl gt RFReason (R ) : The boiling points of alkyl chlorides, bromides and iodides are considerably higher than that of the hydrocarbon of comparable molecular mass.
Answer» ASSERTION and REASON both are CORRECT and reason is correct explanation of assertion. Assertion and reason both are WRONG statements. Assertion is correct but reason is wrong STATEMENT. Assertion and reason both are correct statements but reason is not correct explanation of assertion. Answer :D

Discussion

48.	Assertion (A) : The bleaching of chlorine is temporary. Reason (R ) : Chlorine oxidises ferrous salts to ferric salts.
Answer» A are R are CORRECT and R EXPLAINS A A and R are correct but doesn't explains A A is correct but R is wrong A is wrongbut R is correct Solution :A is wrongbut R is correct

Discussion

49.	Assertion :(A):The average life of radioactive element is infinity. Reason (R): As a radioactive element disintegrates, more of it is formed in nature by itself.
Answer» If both `(A)` and `(R)` are correct , and `(R)` is the correct EXPLANATION of `(A)` If both `(A)` and `(R)` are correct, but (R) is not the correct explanation of `(A)` If `(A)` is correct, but `(R)` is INCORRECT. If `(A)` is incorrect, but `(R)` is correct. Solution :The COMPLETE disintegration of any RADIOACTIVE material is not possible.

Discussion

50.	Assertion (A) : The analgesic and antipyretic aspirin is prepared by the acetylation of salicylic acid. Reason (R) : The acidity of phenol can be explained in terms of the stability of phenoxide ion.
Answer» Both Assertion (A) and REASON (R) are CORRECT statements, and Reason (R) is the correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanationof the Assertion (A). Assertion (A) is correct, but Reason (R) is incorrect statement. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :B

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Assertion (A) : Transparent soaps are made by dissolving soaps in ethanol. Reason (R) : Ethanol makes things invisible.

Assertion (A) Transparent soaps are made by dissolving soaps in ethanol. Reason (R) Ethanol makes things invisible.

Assertion (A) : Transition metals vary widly in their chemical activity. Reason (R) : Many of transition elements are sufficiently electropositive to dissolve in mineral acids.

Assertion (A): Transition metals form large number of complexes. Reason (R): Transition metals are small and highly charged and they have vacant low energy orbitals to accept an electron pair donated by other groups,

Assertion (A) : Transition metals have low melting points. Reason (R ) : The involvement of greater number of (n - 1)d and ns electrons in the interatomic metallic bonding.

Assertion (A) : The vapour pressure of a solution containing non-volatile solute is less thanthe vapour pressure of pure solvent.Reason (R) : In the case of a solution of a non-volatile solute, some of the surface positionsare occupied by the solute.

Assertion (A) : The vapour phase is always richer in the component which is less volatile.Reason (R) : The relative lowering of the vapour pressure of a solution is proportional tomole fraction of the solvent.

Assertion (A) : The weak polarity of ethers does not appreciably affect their boiling points which are comparable to those of alkanes of comparable molecular masses. Reason (R) :Miscibility of ethers with water resembles that of alcohols of the same molecular mass.

Assertion (A) : The values of the rate-constants of simple and complex molecules, determined with the help of Arrhenius equation, are all correct. Reason (R) : A chemical change does not depend on the orientation of the molecules at the moment of a collision.

Assertion (A) : The value of van't Hoff factor denotes the extent of association and dissociationof the solute.Reason (R) : Osmotic pressure is given by the relation pi = (CR)/(T)

Assertion (A) :The two strands in double strand helix structure ofo DNA are complementary to each other Reaso (R ) : Disulphide bonds are formed between specific pairs of bases.

Assertion (A) : The total pressure over the solution in a container is equal to the sum of partialpressure of the components.Reason (R) : The melting point of solution is lowered on addition of a non-volatile soluteinto it.

Assertion (A): The stability of -2 oxidisation state in Group 16 decreases down the Group. Reason (R) : The anomalous behaviour of oxygen is due to its large size and low electronegativity.

Assertion (A) : The representation of rate of reaction I n terms of concentration of the reactants is known as rate law: Reason (R ) : Order of the reaction: CHCl_(3)+Cl_(2) to C Cl_(4)+HClis (3)/(2).

Assertion (A): The stereoisomer's related to each other as non-super imposable mirror images are called enantiomers. Reason (R) : Butan-2-ol has four different groups attached to the tetrahedral carbon and is chiral.

Assertion (A): The process of removing a dissolved substance from a colloidal solution by means of diffusion through a membrane is called dialysis. Reason (R) : Tyndall effect is observed due to the fact that colloidal particles scatter light in all directions in space.

Assertion (A): The process of formation of polymers from respective monomers is called polymerisation. Reason (R) : Polymers have large molecular masses in the range of 10^(3)-10^(7) u.

Assertion (A) : The primary valencies are ionizable and are satisfied by positive ions. Reason (R) : Central atoms/ions in coordination compounds are also referred to as Lewis acids.

Assertion (A): The presence of nitro group facitatesnucleophilicsubstiution reaction in aryl halide. Reason (R):The intermdiate carbonion is stablised due to the presence of the nitro group.

Assertion (A) : The overall decrease in atomic and ionic radii from lanthanum to lutetium is called lanthanoide contraction. Reason (R) : Permanganate titrations can be carried out in the presence of any mineral acid.

Assertion (A) : The outer sphere in the complex compound is called ionisation sphere. Reason (R ) : The groups present in outer sphere are loosely bound to the central metal ion and hence can be separated into ions upon dissolving the complex in the suitable solvent.

Assertion (A) : The nucleus of gold is stable even though there is a very strong coulombic repulsion among the protons. Reason (R) :The inverse square coulomb force is exactly balanced by another inverse square force which is very powerful. i.e.,nuclear force.

Assertion (A) : The molecularity of the reaction H_(2)+Br_(2) to 2HBr appears to be 2. Reason (R ) : Two molecules of the reactants are involved in the given elementary reaction.

Assertion (A): The molecular mass of polymers can be determined by chemical and physical methods. Reason (R) PHBV does not undergo bacterial degradation in the environment.

Assertion (A): The mathematical equation of Freondlich isotherm islog""(x)/(m)=log k -(1)/(n) log p Reason (R) : Oxygen is adsorbed on metals by virtue of oxide formation.

Assertion (A): The minor product obtained in the reaction between CH_(3) CH = CH_(2) " and " HI " is " CH_(3)CH_(2)CH_(2) I. . Reason (R) : Alkyl bromides and iodides develop colour when exposed to light.

Assertion (A): The manufacture of sulphuric acid by contact process is an example of heterogeneous catalysis. Reason (R) : The catalyst Pt (or) V_(2)O_(5)reactants and products are in different phases in contact process.

Assertion (A): The large difference between the melting and boiling points of oxygen and sulphur may be explained on the basis of their atomicity. Reason (R) : Oxygen gas can be obtained by heating salts such as chlorates, nitrates and permanganates.

Assertion (A) : The IUPAC name of benzaldehyde is benzene carbaldehyde. Reason (R) : The carbon-oxygen double bond is polarised due to higher electronegativity of carbon relative to oxygen.

Assertion (A): The highest oxidation state of osmium is (+8). Reason (R ): Osmium is a 5d-block elements

Assertion (A) : The hydrogen attached to nitrogen in sulphonamide is strongly acidic. Reason (R) : Benzene sulphonyl chloride is also known as Hinsberg's reagent.

Assertion (A): The following reaction occurs. Reason (R ): The product is a stable cylic hemiacetal formed by the anion of (A) product of centre is formed, thus (B) is racemate.

Assertion (A) : The extent to which a reaction will proceed can be determined from chemical equilibrium. Reason (R ) : The word kinetics is derived from the Greekword kinesis.

Assertion (A) : The enthalpy of a reaction does not change in the presence of a catalyst.Reason (R) : A catalyst takes part in the reaction, forms an activated complex and reduces the activation energy. However, the energy difference between the reactants and the products remain the same.

Assertion (A) : The empirical mass of ethene is half of its molecular mass. Reason (R) : The empirical formula represents the simplest whole number ratio of various atoms present in a compoud.

Assertion (A) : The elements which give the greatest number of oxidation states occur in or near the middle of the series. Reason (R) : The lowest common oxidation state of transition elements is +2.

Assertion (A): The conversion of fresh precipiate to colloidal state is called peptization Reason ( R) : It is caused by addition of commonions

Assertion (A): The compounds in which the halogen atom is bounded to an sp^(3) hybridised carbon atom adjacent to the carbon-carbon double bond are called vinylic halides. Reason (R) : Common names of alkyl halides are derived by naming the alkyl group folllowed by the name of the halide.

Assertion (A) : The cell potential of mercury cell is 1.35 V which remains constant. Reason (R): In mercury cell, the electrolyte is a paste of KOH and ZnO.

Assertion (A) : The cell potential of mercury cell is 1.35 V which remains constant. Reason (R ) : In mercury cell, the electrolyte is a paste of KOH and ZnO.

Assertion (A) : The catalyst used inFriedel Crafts reaction is anhydrous AlCl_(3). Reason (R) : Anhydrous aluminium chloride is a Lewis acid.

Assertion (A) : The C - O - H bond angle in alcohols in slightly less than the tetrahedral angle. Reason ( R ) : This is due to the repulsive interaction between the two lone electron pairs on oxygen.

Assertion (A): The C-O-C bond angle in eithers is slightly less than tetrahedral angle. Reason (R ): Due to the repulsive interaction between the two alkyl groups in ethers.

Assertion (A): The C-N-C bond angle of trimethyl amine is 108^(@). Reason(R):The bond of C-N -C is due to the repulsion between the bulky methyl groups.

Assertion (A) : The boiling points of alkyl halides decrease in the order : RI gt RBr gt RCl gt RFReason (R ) : The boiling points of alkyl chlorides, bromides and iodides are considerably higher than that of the hydrocarbon of comparable molecular mass.

Assertion (A) : The bleaching of chlorine is temporary. Reason (R ) : Chlorine oxidises ferrous salts to ferric salts.

Assertion :(A):The average life of radioactive element is infinity. Reason (R): As a radioactive element disintegrates, more of it is formed in nature by itself.

Assertion (A) : The analgesic and antipyretic aspirin is prepared by the acetylation of salicylic acid. Reason (R) : The acidity of phenol can be explained in terms of the stability of phenoxide ion.