94420 + Interview Questions in Chemistry in Class 12

1.	Assertion (A): Ester hydrolysis of acid (or) alkali catalyst is an example of homogeneous catalysis. Reason (R) : Ester, H_(2)O acid (or) alkali and the products are in liquid form.
Answer» Both A and R are CORRECT but R is the correct EXPLANATION of A. Both A and R are WRONG. A is correct but R is wrong. A is wrong but R is correct. Answer :A

Discussion

2.	Assertion (A) : Ethanal on treatment with dilute alkali and subsequent heatiing gives but-2-enal. Reason (R ) : Aldehydes and ketones having at least one alpha-hydrogen undergo reaction in the presence of dilute alkali to form aldol.
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, and 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

3.	Assertion (A): Esters and anhydrides are derivatives of carboxylic acids. Reason (R ) :Aldehydes and ketones are widespread in plants and animal kingdom.
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): Enzymes have active sites that hold substrate molecule for a chemical reaction. Reason (R) : Drugs compete with natural substrate by attaching covalently to the active site of enzyme.
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 : Drug compete with natural SUBSTRATE by attaching by WEAK BONDS such as hydrogen bond, Van der Waals. interaction and ionic bonding etc., to the active site of the enzyme.

Discussion

5.	Assertion (A): Enzymes are needed in small quantities for the progress of a reaction. Reason (R): Most of the vitamins can be prepared by our body.
Answer» Both Assertion (A) and Reason (R) are correct statementand Reason (R) is the correctexplanationof the Assertion (A). Both Assertion (A) and Reason (R) are CORRECTSTATEMENTS, but Reason(R) is NOTTHE CORRECTEXPLANATION 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

6.	Assertion (A) : Enzymehaveacitvesitesandsubstrates , reactive sitesontheirsurfacerespectively. Reason (R) : Activeandreactivesitespush the enzymeand substrate moleculesaway form each other .
Answer» Both A and RARE CORRECTAND Ris the CORRECT explaanationof A Both A and Rare correctbut Ris not thecorrectexplanaitonof A . Ais correctbut Ris wrong . A is wrongbut Ris correct . ANSWER :A

Discussion

7.	Assertion (A) : Enzymes are defined as biological protein . Reason (R) : On heating, enzymes do notlose theirspecificactivity .
Answer» Both A and Rare correct and RIS the correct EXPLANATION of A . Both A and Rare worng A is correctbut R is wrong A is wrongbut Ris correct . ANSWER :A

Discussion

8.	Assertion (A) : Enthalpy of mixing of pure components to form the ideal solution is positive. Reason (R) : Volume of mixing of pure components to form the ideal solution is zern.
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) : Elevation in the boiling point of a solution is directly proportional to the molalconcentration of solute.Reason (R) : A solution boils at the temperature at which its vapour pressure is equal to the atmospheric pressure
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

10.	Assertion (A): Elevation in boiling point is a colligative property. Reason (R ): Elevation in boiling point is directly proportional to molarity.
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

11.	Assertion (A) : Electrolytical cell is a device for using electrical energy to carry non-spontaneous chemical reactions. Reason (R) : We can construct innumerable number of galvanic cells on the pattern of Daniel cell by taking combinations of different half-cells.
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

12.	Assertion (A): Electrolysis of water leads to release of hydrogen at the anode and oxygen at the cathode. Reason (R) : All elements of Group 16 except oxygen form dischlorides and dibromides.
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 :D

Discussion

13.	Assertion (A) : Electrochemistry is the study of production of electricity from energy released during spontaneous chemical reactions. Reason (R) : Study of electrochemistry is important for creating new technologies.
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

14.	Assertion (A) : Electrical work done in one second is equal to electrical potential multiplied by total charge passed. Reason (R) : Electrical resistance can be measured with the help of Wheatstone bridge.
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

15.	Assertion (A) : Electrical charge of the particle decreases by boiling the sol. Reason(R) : Collision of molecules of dispersions medium increased by boiling the sol.
Answer» ASSERTION (A) and REASON (R) both are TRUE. (R) is the proper explanation of (A). Assertion (A) and Reason (R) both are true but (R) does not explains (A). Assertion (A) and Reason (R) both are false. Assertion (A) is not true but Reason (R) is true. Solution :Assertion (A) and Reason (R) both are true. (R) is the proper explanation of (A).

Discussion

16.	Assertion (A): Effective and efficient conversion is the special characteristic of enzyme catalysed reactions. Reason (R): An enzyme may transform a million molecules of reactants to products in a minute.
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. A is correct but R is WRONG. A is wrong but R is correct. Answer :A

Discussion

17.	Assertion (A) : Each electron in an atom behaves like a tiny magnet. Reason (R) : Magnetic properties of materials is due to the presence of electrons.
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

18.	Assertion (A) : Doctors adviced to take paracetamol once in 6 hours during fever and body pain Reason (R) : Paracetamol has a half-life of 2.5 hours within the body . After 10 hours (4 half lives ) only 6.25% of drug remains. Based on this , doctors adviced to take it once in 6 hours.
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

19.	Assertion (A) : DNAand RNA molecules are found in the molecules of the cell . Reason (R) : Onheatingenzyme do not lose their specific activity .
Answer» Both A and Rare CORRECTAND Rexplains A. Both A and R are WRONG. A is correctbut RIS wrong A is wrong but Ris correct Answer :B

Discussion

20.	Assertion (A): Dipheyl ether (I) on dinitration gives the product (II). Reason (R ): The ring with first nitro group is deactivated by bar e withdrawing NO_(2) group, so the second nitro group enters the other ring.
Answer» If both (A) and (R ) are TRUE but (R ) is not the CORRECT EXPLANATION of (A). If (A) is true but (R ) is false. If both (A) and (R ) are false. Solution :NA

Discussion

21.	Assertion : A dilute solution of NaCN is used for leaching ores of silver and gold. Reason : Impurities present in these ores dissolve in NaCN
Answer» Both (A) and (R ) are TRUE and (R ) is the CORRECT EXPLANATION of (A). Both (A) and (R ) are true and (R ) is not the correct explanation of (A). (A) true but (R ) false. Both (A) and (R ) are false. Answer :C

Discussion

22.	Assertion (A) : Dinegative anion of oxygen (O^(2-)) is quite common but di-negative anion of sulphur S^(2-) is less common. Reason (R) :Covalency of oxygen is two.
Answer» Both A and R true and R is the CORRECT explanation of A Both A and R true and R is not acorrect explanation of A A is true but R is FALSE A is false but R is true Solution :REASON. Electron AFFINITY of O is more than S.

Discussion

23.	Assertion (A) : Dichloromethane is used as a solvent and as a paint-remover.Reason (R) : Carbon tetrachloride was earlier used as an antiseptic.
Answer» Both Assertion (A) and Rersou (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 Renson (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Renson (R) is INCORRECT statement. Assertion (A) is incorrect, but Reason (R) is correct statement. Answer :C

Discussion

24.	Assertion (A): Diborane is highly reactive. Reason(R):At high temperatures, diborane forms higher boranes.
Answer» ANSWER :B

Discussion

25.	Assertion (A) : Diamond and Silicon carbide are very hard and have high melting point. Reason (R) : In covalent solids, the atoms are bound together in a three dimensional network entirely by covalent bonds.
Answer» Both A and R are CORRECT but R is not the correct EXPLANATION of A Both A and R are correct and R is 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 is the correct explanation of A.

Discussion

26.	Assertion (A) : Diamagnetic substances are attracted by magnetic fields. Reason : Ferromagnetic substances are strongly attracted by magnetic field.
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

27.	Assertion (A) : Detergents with low CMC are more economical to use. Reason (R) : Cleansing action of detergents involves the formation of micelle. These are formed when the concentration of detergents becomes equal to CMC.
Answer» ASSERTION and REASON are correct and reason is correct EXPLANATION of assertion. Assertion and reason both are correct but reason does not explain assertion. Assertion is correct but reason is INCORRECT. Both assertion and reason are incorrect. SOLUTION :Assertion and reason are correct and reason is correct explanation of assertion.

Discussion

28.	Assertion (A) : Deoxyribose, C_(5)H_(10)O_(4), is not a carbohydrate. Reason (R) : Carbohydrates are hydrates of carbon so compounds which follow C_(x)(H_(2)O)_(y) formula are carbohydrates.
Answer» Assertion and REASON both are CORRECT statements and reason EXPLAINS the assertion. Both assertion and reason are WRONG statements. Assertion is correct statement and reason is wrong statement. Assertion is wrong statement and reason is correct statement. SOLUTION :Both assertion and reason are wrong statements. Deoxyribose is a carbohydrate

Discussion

29.	Assertion (A) : DDT as an insecticide is still being used worldwide on a large scale as a safe treatment. Reason (R) : Carbon tetrachloride has been found to be responsible for depletion of ozone layer.
Answer» Both ASSERTION (A) and Rersou (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 Renson (R) is not the correct explanation of the Assertion (A). Assertion (A) is correct, but Renson (R) is incorrect statement. Assertion (A) is incorrect, but Reason (R) is correct statement. ANSWER :d

Discussion

30.	Assertion (A) : Decomposition of hydrogen first order reaction . Reaction (R) : The above reaction take place in two steps, step I involved both H_2O_2 and I^(-)and so it is bimolecular but order is determined experimentally as 1 .
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

31.	Assertion (A) D-glucose when dissolved in water undergo mutarotation while sucrose solution does not show mutarotation Reason(R) D-glucose exist in two cyclic anomeric forms.
Answer» ANSWER :B

Discussion

32.	Assertion (A) : Daniel cell has a potential of 2.1 V when concentrations of ions is unity, Reason (R) : The two parts of Zn-Cu cell are connected by salt bridge.
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

33.	Assertion (A) : Cu^(2+) iodide is not known Reason (R ): Cu^(2+) oxidizes I^(-) to iodine
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 :Both assertion and reason are true and reason is the correct explanation of the assertion `2CU^(2+) + 4I^(-) RARR Cu_(2)I_(2) + I_(2)`

Discussion

34.	Assertion (A) : D-(+)-Glucose is a dextrorotatory in nature. Reason (R) : 'D' represents its dextrorotatory nature.
Answer» Assertion and REASON both are correct statements and reason explains the assertion. Both assertion and reason are wrong statements. Assertion is correct statement and reason is wrong statement. Assertion is wrong statement and reason is correct statement. Solution :Assertion is correct statement and reason is wrong statement. .D. REPRESENTS the position of -OH group of FARTHEST asymmetric carbon from aldehyde group on right HAND SIDE.

Discussion

35.	Assertion (A) : Current stops flowing when E_("cell") = 0 Reason (R) : At E_("cell") = 0, Equilibrium of the cell reaction is attained.
Answer» Both A and R are CORRECT Both A and R are WRONG A is correct but R is wrong A is wrong but R is correct ANSWER :A

Discussion

36.	Assertion (A) : Cu^(2+) + 2e^(-) to Cu (s) is an example of oxidation half reaction. Reason (R) : When concentrations of all species involved in a half-cell is unity, then the electrode potential is called standard electrode potential.
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

37.	Assertion (A) : Cyclohexylamine is weaker than aniline. Reason (R) : The lone pair of electrons on nitrogen is delocalised over benzene nucleus in aniline. The lone pair of electrons on nitrogen in cyclohexyl amine is localised.
Answer» Both A and R are TRUE and R is the CORRECT EXPLANATION of A. Both A and R are true but R is not a correct explanation of A. A is true but R is FALSE. A is false but R is false. Answer :D

Discussion

38.	Assertion (A) : Cuprite is concentration by froth floatation process. Reason (R ) : Cuprite is the sulphide ore
Answer» Both (A) and (R ) are TRUE and (R ) is the CORRECT EXPLANATION of (A). Both (A) and (R ) are true and (R ) is not the correct explanation of (A). (A) true but (R ) false. Both (A) and (R ) are false. Answer :D

Discussion

39.	Assertion (A): Cu cannot liberate hydrogen from acids. Reason (R ): Because it has positive electrode potential.
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 :Cu has `E^(@)` VALUE of (+0.34V). So, it cannot reduce `H^(+)` of acids to `H_(2)`.

Discussion

40.	Assertion (A) : Crystalline solids are anisotropic in nature. Reason (R) : Anisotropy is the property which depends on the direction of measurement. Crystalline solids are anisotropic and they show different values of physical properties when measured along different directions. Both A and R are correct and R is the correct explanation of A.
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 SOLUTION :Both A and R are correct and R is the correct explanation of A.

Discussion

41.	Assertion: A crystal with schottky defect is electrically neutraly Reason : Equal number of cation and anion vacanies are present
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 :a

Discussion

42.	Assertion (A): Cr and Cu having [Ar] 3d^(5)4s^(1) and [Ar] 3d^(10) 4s^(1) are more stable. Reason (R): The extra stability of elements Cr and Cu is due to symmetrical distribution of electrons and exchange energy.
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

43.	Assertion (A) : Copper sulphate can be stored in a Zinc vessel. Reason (R) : Zinc is less reactive than Copper.
Answer» Both A and R are CORRECT Both A and R are WRONG A is correct but R is wrong A is wrong but R is correct ANSWER :B

Discussion

44.	Assertion (A): Copolymers have properties quite different from homopolymers. Reason (R) : Rubber is a natural polymer and possesses elastic properties.
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

45.	Assertion (A): Copper is unique in 3d series having a stable +1 oxidation state. Reason (R): Copper is prone to disproportionate to the +2 and 0 oxidation states.
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 but (R) is not the correct explanation of (A).

Discussion

46.	Assertion (A) : Coordination isomerism arises in a coordination compound containing ambidentate group. Reason (R) : Optical isomers are mirror images that cannot be superimposed on each other.
Answer» Both Assertion (A) and REASON (R) are CORRECT statements, and Reason (R) is tire correct EXPLANATION of the Assertion (A). Both Assertion (A) and Reason (R) are correct statements,, but Reason (R) is not the corret 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

47.	Assertion (A) : Coordination compounds find extensive applications in metallurgical processes, analytical and medicinal chemistry. Reason (R) : In black and white photography, the developed film is fixed by washing with hypo solution.
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 :B

Discussion

48.	Assertion (A) : [Co(NH_(3))_(6)][Cr(CN)_(6)] can exist in coordination isomerism. Reason (R ) : In a bimetallic complex, the interchange of one or more ligands between the cationic and the anionic coordination entities result in coordination isomerism
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

49.	Assertion (A) : [Co(NH_(3))_(4)Br_(2)]Cl and [Co(NH_(3))_(4)ClBr]Br are examples of ionisation isomers. Reason (R ) : The exchange of counter ions with one or more ligands in the coordination entity will result in ionisation isomers
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 and R are WRONG A is wrong but R is correct Answer :B

Discussion

50.	Assertion (A) : [Co(NH_(3))_(6)]^(3+) and [Fe(H_(2)O)_(6)]^(2+) are homoleptic complexes Reason (R ) : The central metal ion/atom is coordinated to only one kind of ligands is called a homoleptic complex.
Answer» Both A and R are wrong A is CORRECT but R wrong 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. Answer :A

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Assertion (A): Ester hydrolysis of acid (or) alkali catalyst is an example of homogeneous catalysis. Reason (R) : Ester, H_(2)O acid (or) alkali and the products are in liquid form.

Assertion (A) : Ethanal on treatment with dilute alkali and subsequent heatiing gives but-2-enal. Reason (R ) : Aldehydes and ketones having at least one alpha-hydrogen undergo reaction in the presence of dilute alkali to form aldol.

Assertion (A): Esters and anhydrides are derivatives of carboxylic acids. Reason (R ) :Aldehydes and ketones are widespread in plants and animal kingdom.

Assertion (A): Enzymes have active sites that hold substrate molecule for a chemical reaction. Reason (R) : Drugs compete with natural substrate by attaching covalently to the active site of enzyme.

Assertion (A): Enzymes are needed in small quantities for the progress of a reaction. Reason (R): Most of the vitamins can be prepared by our body.

Assertion (A) : Enzymehaveacitvesitesandsubstrates , reactive sitesontheirsurfacerespectively. Reason (R) : Activeandreactivesitespush the enzymeand substrate moleculesaway form each other .

Assertion (A) : Enzymes are defined as biological protein . Reason (R) : On heating, enzymes do notlose theirspecificactivity .

Assertion (A) : Enthalpy of mixing of pure components to form the ideal solution is positive. Reason (R) : Volume of mixing of pure components to form the ideal solution is zern.

Assertion (A) : Elevation in the boiling point of a solution is directly proportional to the molalconcentration of solute.Reason (R) : A solution boils at the temperature at which its vapour pressure is equal to the atmospheric pressure

Assertion (A): Elevation in boiling point is a colligative property. Reason (R ): Elevation in boiling point is directly proportional to molarity.

Assertion (A) : Electrolytical cell is a device for using electrical energy to carry non-spontaneous chemical reactions. Reason (R) : We can construct innumerable number of galvanic cells on the pattern of Daniel cell by taking combinations of different half-cells.

Assertion (A): Electrolysis of water leads to release of hydrogen at the anode and oxygen at the cathode. Reason (R) : All elements of Group 16 except oxygen form dischlorides and dibromides.

Assertion (A) : Electrochemistry is the study of production of electricity from energy released during spontaneous chemical reactions. Reason (R) : Study of electrochemistry is important for creating new technologies.

Assertion (A) : Electrical work done in one second is equal to electrical potential multiplied by total charge passed. Reason (R) : Electrical resistance can be measured with the help of Wheatstone bridge.

Assertion (A) : Electrical charge of the particle decreases by boiling the sol. Reason(R) : Collision of molecules of dispersions medium increased by boiling the sol.

Assertion (A): Effective and efficient conversion is the special characteristic of enzyme catalysed reactions. Reason (R): An enzyme may transform a million molecules of reactants to products in a minute.

Assertion (A) : Each electron in an atom behaves like a tiny magnet. Reason (R) : Magnetic properties of materials is due to the presence of electrons.

Assertion (A) : Doctors adviced to take paracetamol once in 6 hours during fever and body pain Reason (R) : Paracetamol has a half-life of 2.5 hours within the body . After 10 hours (4 half lives ) only 6.25% of drug remains. Based on this , doctors adviced to take it once in 6 hours.

Assertion (A) : DNAand RNA molecules are found in the molecules of the cell . Reason (R) : Onheatingenzyme do not lose their specific activity .

Assertion (A): Dipheyl ether (I) on dinitration gives the product (II). Reason (R ): The ring with first nitro group is deactivated by bar e withdrawing NO_(2) group, so the second nitro group enters the other ring.

Assertion : A dilute solution of NaCN is used for leaching ores of silver and gold. Reason : Impurities present in these ores dissolve in NaCN

Assertion (A) : Dinegative anion of oxygen (O^(2-)) is quite common but di-negative anion of sulphur S^(2-) is less common. Reason (R) :Covalency of oxygen is two.

Assertion (A) : Dichloromethane is used as a solvent and as a paint-remover.Reason (R) : Carbon tetrachloride was earlier used as an antiseptic.

Assertion (A): Diborane is highly reactive. Reason(R):At high temperatures, diborane forms higher boranes.

Assertion (A) : Diamond and Silicon carbide are very hard and have high melting point. Reason (R) : In covalent solids, the atoms are bound together in a three dimensional network entirely by covalent bonds.

Assertion (A) : Diamagnetic substances are attracted by magnetic fields. Reason : Ferromagnetic substances are strongly attracted by magnetic field.

Assertion (A) : Detergents with low CMC are more economical to use. Reason (R) : Cleansing action of detergents involves the formation of micelle. These are formed when the concentration of detergents becomes equal to CMC.

Assertion (A) : Deoxyribose, C_(5)H_(10)O_(4), is not a carbohydrate. Reason (R) : Carbohydrates are hydrates of carbon so compounds which follow C_(x)(H_(2)O)_(y) formula are carbohydrates.

Assertion (A) : DDT as an insecticide is still being used worldwide on a large scale as a safe treatment. Reason (R) : Carbon tetrachloride has been found to be responsible for depletion of ozone layer.

Assertion (A) : Decomposition of hydrogen first order reaction . Reaction (R) : The above reaction take place in two steps, step I involved both H_2O_2 and I^(-)and so it is bimolecular but order is determined experimentally as 1 .

Assertion (A) D-glucose when dissolved in water undergo mutarotation while sucrose solution does not show mutarotation Reason(R) D-glucose exist in two cyclic anomeric forms.

Assertion (A) : Daniel cell has a potential of 2.1 V when concentrations of ions is unity, Reason (R) : The two parts of Zn-Cu cell are connected by salt bridge.

Assertion (A) : Cu^(2+) iodide is not known Reason (R ): Cu^(2+) oxidizes I^(-) to iodine

Assertion (A) : D-(+)-Glucose is a dextrorotatory in nature. Reason (R) : 'D' represents its dextrorotatory nature.

Assertion (A) : Current stops flowing when E_("cell") = 0 Reason (R) : At E_("cell") = 0, Equilibrium of the cell reaction is attained.

Assertion (A) : Cu^(2+) + 2e^(-) to Cu (s) is an example of oxidation half reaction. Reason (R) : When concentrations of all species involved in a half-cell is unity, then the electrode potential is called standard electrode potential.

Assertion (A) : Cyclohexylamine is weaker than aniline. Reason (R) : The lone pair of electrons on nitrogen is delocalised over benzene nucleus in aniline. The lone pair of electrons on nitrogen in cyclohexyl amine is localised.

Assertion (A) : Cuprite is concentration by froth floatation process. Reason (R ) : Cuprite is the sulphide ore

Assertion (A): Cu cannot liberate hydrogen from acids. Reason (R ): Because it has positive electrode potential.

Assertion: A crystal with schottky defect is electrically neutraly Reason : Equal number of cation and anion vacanies are present

Assertion (A): Cr and Cu having [Ar] 3d^(5)4s^(1) and [Ar] 3d^(10) 4s^(1) are more stable. Reason (R): The extra stability of elements Cr and Cu is due to symmetrical distribution of electrons and exchange energy.

Assertion (A) : Copper sulphate can be stored in a Zinc vessel. Reason (R) : Zinc is less reactive than Copper.

Assertion (A): Copolymers have properties quite different from homopolymers. Reason (R) : Rubber is a natural polymer and possesses elastic properties.

Assertion (A): Copper is unique in 3d series having a stable +1 oxidation state. Reason (R): Copper is prone to disproportionate to the +2 and 0 oxidation states.

Assertion (A) : Coordination isomerism arises in a coordination compound containing ambidentate group. Reason (R) : Optical isomers are mirror images that cannot be superimposed on each other.

Assertion (A) : Coordination compounds find extensive applications in metallurgical processes, analytical and medicinal chemistry. Reason (R) : In black and white photography, the developed film is fixed by washing with hypo solution.

Assertion (A) : [Co(NH_(3))_(6)][Cr(CN)_(6)] can exist in coordination isomerism. Reason (R ) : In a bimetallic complex, the interchange of one or more ligands between the cationic and the anionic coordination entities result in coordination isomerism

Assertion (A) : [Co(NH_(3))_(4)Br_(2)]Cl and [Co(NH_(3))_(4)ClBr]Br are examples of ionisation isomers. Reason (R ) : The exchange of counter ions with one or more ligands in the coordination entity will result in ionisation isomers

Assertion (A) : [Co(NH_(3))_(6)]^(3+) and [Fe(H_(2)O)_(6)]^(2+) are homoleptic complexes Reason (R ) : The central metal ion/atom is coordinated to only one kind of ligands is called a homoleptic complex.