52671 + Interview Questions in Chemistry in Class 11

1.	Assertion (A): Covalent radius is always shorter than the actual atomic radius.Reason (R): The formation of covalent bond involves the overlapping of atomic orbitals and it reduces the expected internuclear distance.
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

2.	Assertion (A) : Cr with electronic configuration [Ar]3d54s1 is more stable than [Ar]3d44s2 .Reason (R):Half filled orbitals have been found to have extra stability than partially filled orbitals.
Answer» A and R are CORRECT and R is the correct EXPLANATION of A. A and R are correct but R is not the correct the explanation of A. A is correct but R is WRONG. A is wrong but R is correct. Answer :A

Discussion

3.	Assertion (A): Cr with electronic configuration [Ar]3d^(5) 4s^(1) is more stable than (Ar) 3d^(4) 4s^(2s)Reason (R): Half filled orbitals have been found to have extra stability than partially filled orbitals
Answer» A and R are CORRECT and R is the correct EXPLANATION of A 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

4.	Assertion (A): Copper (Z=29) with electronic configuration [Ar] 4s1 3d10is more stable than [Ar]s 2 3d9.Reason (R): Copper with [Ar] 4s1 3d10is more stable due to symmetrical distribution and exchange energies of 4 electrons.
Answer» A and R are CORRECT and R is the correct EXPLANATION of A. A and R are correct but R is not the correct the explanation of A. A is correct but R is WRONG. A is wrong but R is correct. Answer :A

Discussion

5.	Assertion (A) : Compounds of a mixture of red and blue inks can be separated by distributing the compounds between stationary and mobile phases in paper chromatography. Reason (R) : The coloured components of inks migrate at different rates because paper selectively retains different components according to the difference in their partition between the two phases.
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. Both A and R are not correct A is not correct but R is correct Solution :REASON is the correct explanation for ASSERTION

Discussion

6.	Assertion (A): Compressibility factor for hydrogen varies with pressure with positive slope at all pressures Reason (R):Even at low pressures, repulsive forces dominate in hydrogen gas.
Answer» A & R are true, R explains A A & R are true, R does not explain A A is true R is false A is false R is true Solution :Z for `h_1 = 1 + P (b/(RT))` i.e., `Z > 1 implies ` repulsive forces.

Discussion

7.	Assertion (A) : Components of a mixture of red and blue inks can be separated by disturbing the component between stationary and mobile phases in paper chromatography. Reason (R) : The coloured components of inks migrate at different rates because paper selectively retains different components according to the difference in their partition between the two phases.
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. Both A and R are not correct. A is not correct but R is correct. Solution :R is the correct explanation of A.

Discussion

8.	Assertion (A): Components of a mixture of red and blue inks can be separated by distributing the components between stationary and mobile phases in paper chromatography. Reason ( R): The coloured components of inks migrate at different rates because paper selectively retains different components according to the difference in their partition between the two phases
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) Both (A) and (R ) are not correct (A) is not correct but (R ) is correct Answer :A

Discussion

9.	Assertion (A) : Combustion of 16 g of methane gives 18 g of water. Reason (R) : In the combustion of methane, water is one of the products.
Answer» Both A and R are true but R is not 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 :Combustion of methane gives 36 G of water. `{:(" "CH_(4)+2O_(2)rarrCO_(2)+2H_(2)O),(1mol=16 g "" 2 MOL = 36 g ):}`

Discussion

10.	Assertion (A): Colour of KMnO_4 disappears when dihydrogen gas is bubbled through it. Reason (R) :Dihydrogen gas is highly inflammable.
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 notthe correct explanation of (A). If (A) is correct, but (R) is INCORRECT. If (A) is incorrect, but (R) is correct. Solution :`KMnO_(4)+H_(2)to`No reaction

Discussion

11.	Assertion (A) : Colloidal solution are stable but the colloidal particles do not settle down. Reason (R): Brownian movement counters the force of gravity actively on colloidal particles.
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 true Answer :A

Discussion

12.	Assertion (A): Chloroform vapours can be used as an anaesthetie. Reason (R): Chloroform vapours depresses the central nervous system and cause unconsciousness.
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 but (R) is not the correct explanation of (A).

Discussion

13.	Assertion (A): Chlorine water has antibacterial action and also used as bleach. Reason (R): Chlorine reacts with water to give hydrochloric acid and hypochlorous acid which are found in many applications.
Answer» Both (A) and (R) are CORRECT AUD (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

14.	Assertion (A): Chloro benzene is prepared by Sandmayer reaction or Gattermann reaction using benzene diazonium chloride. Reason (R): When aqueous solution of benzene diazonium chloride is warmed with Cu_(2)Cl_(2) in HCl give chloro benzene.
Answer» Both (A) and (R) are TRUE. (A) true but (R) FALSE. (A) false but (R) true. Both (A) and (R) are false. Solution :Both (A) and (R) are true.

Discussion

15.	Assertion (A): Chemical equilibrium is in a state of dynamic equilibrium. Reason (R): At equilibrium the forward and backward reactions are proceeding at the same rate and no macroscopic change is observed.
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 :Assertion (A): Chemical equilibrium is in a state of DYNAMIC equilibrium. Reason (R): At equilibrium the forward and backward reactions are proceeding at the same RATE and no macroscopic change is observed.

Discussion

16.	Assertion (A) : CH_(4) , CO_(2) has value of Z (compressibility factor )less than one a 0^(@) C . Reason (R) : For every molecule there are three rotational degree of freedom .
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 the correct explanation of Assertion . Assertion is true but Reason is WRONG . Both Assertion and Reason are wrong . ANSWER :A

Discussion

17.	Assertion (A) :CH_(3) -BH - overset(+) CH_(2)connot show resonance. Reason (R) : Boron and carbocation both are electron defficient species .
Answer» Both A and R are ture and R is the correct EXPLANATION of A . Both A and R are true but R is not correct explanation of A. A is truebut R is false Both A and R are false SOLUTION :N/A

Discussion

18.	Assertion (A) :CH_(3)-CH-CH_(3) has 6 hyper-conjugative hydrogens. WhileCH_(3)-CH-CH_(2)-CH_(3)has 5 hyper-conjugative hydrogens. Reason (R):CH_(3) -overset(+)CH -CH_(3) is more stable than CH_(3) - overset(+)CH -CH_(2) -CH_(3)
Answer» Both A and R are TURE and R is the correct EXPLANATION of A . Both A and R are TRUE but R is not correct explanation of A. A is truebut R is false Both A and R are false Solution :N/A

Discussion

19.	Assertion: A catalyst is more effective in finely divided form. Reason: Finely divided form the more surface area.
Answer» if both assertion and reason are TRUE and the reason is the CORRECT explanation of the assertion. if both assertion and reson are true but reason is not the correct explanation of the assertion. If assertion is true but reason is false. If the assertion and reason both are false. Solution :A catalyst is more effective in finely DIVIDED form because finely divided form has more surface area. Therefore there is an increase in active centres on the surface.

Discussion

20.	Assertion : A catalyst does no alter the equilibrium constant of a reaction. Reason : The catalyst forms a complex with the reactant and provides an alternate path with lowe energy of in activation for the reaction. The forward and reverse reaction are affected to the same extent.
Answer» if both ASSERTION and REASON are CORRECT and reason is CORRECTEXPLANATION for assertion. if both assertion and reason are correct but reason is not correct EXPLANATION for assertion. if assertion is correct but reason is incorrect. if assertion and reason boht are incorrect. Solution :Reason is the correct explanation for assertion .

Discussion

21.	Assertion (A): Carbon halogen bond is a polar bond. Reason (R): Halogens are more elective negative than carbon.
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. Solution :Both (A) and (R) are true and (R) is the correct explanation of (A).

Discussion

22.	Assertion (A) : Carbon dioxide is one of the important greenhouse gases.Reason (R) : It is largely produced by respiratory function of animals and plants.
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). Both (A) and (R) are not correct. (A) is not correct but R is correct. Solution : Carbon DIOXIDE is one of the important green house gases. Which largely produced by the combustion of fossil fuels like natural gas, coal, petroleum, etc. It is ALSO produced by respiratory function of lining ORGANISMS like plants and ANIMALS.

Discussion

23.	Assertion (A) : Carbon dioxide is one of the important greenhouse gases Reason (R): It is largely produced by respiratory function of animals and plants
Answer» Both Assertion and REASON are correct and is the correct EXPLANATION of Assertion Both Assertion and Reason are correct but Reasonis not the correct explanation of Assertion Both Assertion and Reason are not correct Assertion is not correct but Reason is correct Solution :Correct Explanation. It is largely PRODUCED by the combustion of fossil fuels like coal, NATURAL gas, petroleum, ETC

Discussion

24.	Assertion (A) Calgon is used for removingCA^(2+) and Mg^(2+) ions from hard water. Reason (R ) Calgon forms precipitates with Ca^(2+) and Mg^(2+)
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 fales Both A and R are fales. Solution :Both assertion (A) and reason ( R) are not true. Correct Assertion : Calgon mask the properties of `Ca^(2+)` and `MG^(2+)` ions present in water without REMOVING them as ppt. Correct Reason. Calgon forms soluble complexes with `Ca^(2+)` and `Mg^(2+)` in which properties of these ions are masked.

Discussion

25.	Assertion (A): Carbon cannot form ionic bond. Reason (R): It is not possible for the carbon to form either C^(4+) or C^(4-) ions, as it requires large amount of energy.
Answer» Both A and R are CORRECT and R is the correct EXPLANATION of assertion. Both A and R are correct but R is not the correct explanation of assertion. A is correct.but R is WRONG A is wrong but R is correct. Answer :A

Discussion

26.	Assertion (A) :C_(2) H_(5) - overset(+)CH-C_(2) H_(5)is more stable thenCH_(3) - overset (+)CH -CH_(3) Reason (R) : Positive inductive effective ofC_(2) H_(5) -group is less thanCH_(3)- group .
Answer» Both A and R are TURE and R is the correct EXPLANATION of A . Both A and R are TRUE but R is not correct explanation of A. A is truebut R is false Both A and R are false Solution :N/A

Discussion

27.	Assertion (A) :BrCl + Ican form to 6 different geometrical isomers . Reason (R) : Each one structure is geometrical isomere of other five structures .
Answer» Both A and R are ture and R is the CORRECT explanation of A . Both A and R are TRUE but R is not correct explanation of A. A is truebut R is FALSE Both A and R are false SOLUTION :N/A

Discussion

28.	Assertion (A) : Boronhas smallerfirstionisation enthalpy than beryllium Reason( R ) :The penetrationof a 2s electron to thenucleusis more than the2pelectronhence 2p- electronis moreshieldedby the innercore ofelectrons than 2selectrons .
Answer» ASSERTION andreasonboth arecorrectstatementbut REASONIS notcorrectexplanation for assertion Assertion is correctstatementbut reasonis wrongstatement. Assertion ANDREASON BOTHARE correctstatementand reasonis correctexplanationfor assertion Assertion isreasonboth arewrongstatements. Solution :NA

Discussion

29.	Assertion (A) : Boron has a smaller first ionisation enthalpy than beryllium Reason (R): The penetration of a 2s electron to the nucleus is more than the 2p electron hence 2p electron is more shielded by the inner core of electrons than the 2s electrons.
Answer» Assertion and reason both are correct STATEMENTS but reason is not correct explanation for assertion. Assertion is correct statement but reason is wrong statement Assertion and reason both are correct statements and reason is correct explanation for assertion. Assertion and reason both are wrong statements. Solution :Boron has a smaller `1^(st)` ionisation enthalpy than of BERYLLIUM because INTRODUCING an electron into a 2S orbital is more than the 2p orbital. Hence, 2p electron is more shielded by the inner core of electron than the 2s electron.

Discussion

30.	Assertion (A) : Boric acid behaves as a weak monobasic acid. Reason (R) : Boric acid contains H-bonds in its structure.
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 true Solution :Reason. `B(OH)_(3)+H_(2)O hArr [B(OH)_(4)]^(-)+H^(+)`

Discussion

31.	Assertion (A) : Boron always forms covalent bond. Reason (R) :The small size of B^(3+) favours formation of covalent bond.
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 true Answer :A

Discussion

32.	Assertion (A) : Bohr's orbits are also called stationary states. Reason (R ) : Electrons are stationary is an orbit.
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 is true but R is false Both AAND R are false ANSWER :C

Discussion

33.	Assertion (A) : B(OH)_(3) is weakly basic. Reason (R) : B-O bonds can be broken easily.
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 Both A and R are false. Solution :`B(OH)_(3)` is a weak ACID and when dissolved in water `B-O` bonds do not break.

Discussion

34.	Assertion (A) : B(OH)_(3) is acidic while In(OH)_(3) is basic. Reason (R) : B(OH)_(3) has highly H-bonded net-work structure.
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 true Solution :REASON. `H_(3)BO_(3)` (or `B(OH)_(3)`) is an acid because B is a TYPICAL non-metal while `In(OH)_(3)` is a base because it is a typical metal.

Discussion

35.	Assertion (A) : Black body is an ideal body that emits and absorbs radiations of all frequencies. Reason (R) : The frequency of radiation emitted by a body goes from a lower frequency to higher frequency with an increase in temperature.
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 is true and R is false. Both A and R are false. Solution :Assertion is true and REASON is false. The body which absorbs and emits all RADIATIONS at all frequency is called perfect black body. With rise in temperature, frequency increases.

Discussion

36.	Assertion (A): Black body is an ideal body that emits and absorbs radiations of all frequencies Reason (R) : The frequency of radiation emitted by a body goes from a lower frequency to higher frequency with an increase in temperature
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 the correct explanation of A A is true but R is false Both A and R are false Solution :Correct explanation. Black BODY is a perfect ABSORBER and perfect radiator of energy

Discussion

37.	Assertion (A) : Beryllium carbonate is unstable and decomposes to give beryllium oxide and carbon dioxide . Reason (R) : Beryllium carbonate is unstable and decomposes to give beryllium oxide and carbon dioxide .
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. Both A and R are not correct A is not correct but R is correct. Solution :Both A and R are correct and R is the CORRET explanation of A .

Discussion

38.	Assertion (A) : Beryllium carbonate is kept in the atmosphere of carbon dioxide. Reason (R) : Beryllium carbonate is unstable and decomposes to give beryllium oxide and carbon dioxide.
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. Both A and R are not correct. A is not correct but R is correct Solution :BeO is more stable dueto SMALL size asnd strong polarizing power of `Be^(2+)`. As BeO is stable and `BeCO_(3)` is unstable. When it is kept in the ATMOSPHERE of `CO_(2)` a reversible process occurs and stability of `BeCO_(3)` increases.

Discussion

39.	Assertion (A): B_(2), O_(2), NO are paramagnetic in nature.
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 corTect. Solution :Both (A) and (R) are correct but (R) is not the correct explanation of (A).

Discussion

40.	Assertion (A): Atomic radius tends to decrease across a period.Reason (R): As we move from left to right along a period, the valence electrons are added to the same shell, nuclear charge increases and atomic radius decreases.
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

41.	Assertion (A) : Atmosphere contains small amount of poisonous gases but they are preferably adsorbed on activated charcoal. Reason (R): On a particular adsorbent, the more strongly adsorbable adsorbate adsorbs to a greater extent than its partial pressure indicates.
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 true Answer :A

Discussion

42.	Assertion (A) : At critical temperature, liquid passes into gaseous state imperceptibly and continuously. Reason (R ) : The density of liquid and gaseous phase is equal at critical temperature.
Answer» Both A and R are TRUE and R is the CORRECT explanation of A. Both A and R are true R is not the correct explanation of A. A is true but R is FALSE. A is false but R is true. ANSWER :A

Discussion

43.	Assertion (A) : At critical temperature liquid passes into gaseous state imperceptibly and continuously.Reason (R ) : The density of liquid and gaseous phase is equal to critical temperature.
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 the correct explanation of A A is true but R is FALSE. A is false but R is true. Solution :Both assertion and reason are true and reason is the correct explanation of assertion. At Tc, density of GASEOUS phase and LIQUID are equal due to which liquid passes into gaseous state imperceptibly and continuously.

Discussion

44.	Assertion (A) : At constant temperature, pV vs V plot for real gases is not a straight line.Reason (R ) : At high pressure all gases have Z gt 1 but at intermediate pressure most gases have Z lt 1.
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 the correct explanation of A A is true but R is false. A is false but R is true. Solution :Both assertion and reason are true but reason is not the correct explanation of assertion. At constant temperature, PV vs V for real gases is not a straight LINE as real gases POSSESSES intermolecular FORCES of attraction.

Discussion

45.	Assertion (A): At a given temperature 1 mole of any gas has same kinetic energy. Reason (R):Kinetic energy = (3/2)RT (for 1mole of gas).
Answer» A & R are true, R explains A A & R are true, R does not EXPLAIN A A is true R is FALSE A is false R is true Solution :`KE = 3/2 RT` for 1 mole.

Discussion

46.	Assertion (A) : At constant temperature, pV vs. V plot for real gases is not straight line. Reason (R ) : At high pressure, all gases have Z gt 1 but at intermediate pressure, most gases have Z lt 1.
Answer» Both A and R are TRUE and R is the correct EXPLANATION of A. Both A and R are true R is not the correct explanation of A. A is true but R is false. A is false but R is true. Solution :Correct explanation. At CONSTANT TEMPERATURE, plot of pV vs. V for REAL gases is not linear because real gases have intermolecular forces of attraction.

Discussion

47.	Assertion (A) : Aqueous solutions of ZnSO_4is neutral. Reason ( R ):Salt of strong base and weak acid undergoes anionic hydrolysis.
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 ) is true but (R ) is false (A ) is false but (R ) is true Solution :`Zn^(+2)` undergoes hydrolysis and give acidic solution.

Discussion

48.	Assertion (A) : Aqueous solution of Na_2CO_3show p^(H) gt 7. Reason ( R ):Salt of strong base and weak acid undergoes anionic hydrolysis.
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 ) is true but (R ) is false (A ) is false but (R ) is true Solution :`CO_3^(2-) ` UNDERGOES HYDROLYSIS and gives basic solution.

Discussion

49.	Assertion (A): Aqueous solution of ammonium acetate is neutral Reason(R): Dissociation constants of NH_(4),OH(K_(6)) and that of CH_(3),COOH (K_(a)) are nearly equal.
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 ) is true but (R ) is FALSE (A ) is false but (R ) is true SOLUTION :pKaof `CH_3COOH =pKb ` of ` NH_4OH` `therefore PH" of "CH_3COONH_4 = 7`

Discussion

50.	Assertion (A) : Aqueous solution of ammonium carbonate is basic. Reason (R) : Acidic/basic nature of a salt solution ofa salt of weak acid and weak base depends on K_(a) and K_(b) value of the acid and the base forming it.
Answer» Both A and Rare TRUEAND R is the correct EXPLANATION of A. Both A and Rare truebutR is NOTTHE correct explanation of A. A is true but R is false. Both A and R are false. Answer :A

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Assertion (A): Covalent radius is always shorter than the actual atomic radius.Reason (R): The formation of covalent bond involves the overlapping of atomic orbitals and it reduces the expected internuclear distance.

Assertion (A) : Cr with electronic configuration [Ar]3d54s1 is more stable than [Ar]3d44s2 .Reason (R):Half filled orbitals have been found to have extra stability than partially filled orbitals.

Assertion (A): Cr with electronic configuration [Ar]3d^(5) 4s^(1) is more stable than (Ar) 3d^(4) 4s^(2s)Reason (R): Half filled orbitals have been found to have extra stability than partially filled orbitals

Assertion (A): Copper (Z=29) with electronic configuration [Ar] 4s1 3d10is more stable than [Ar]s 2 3d9.Reason (R): Copper with [Ar] 4s1 3d10is more stable due to symmetrical distribution and exchange energies of 4 electrons.

Assertion (A): Compressibility factor for hydrogen varies with pressure with positive slope at all pressures Reason (R):Even at low pressures, repulsive forces dominate in hydrogen gas.

Assertion (A) : Combustion of 16 g of methane gives 18 g of water. Reason (R) : In the combustion of methane, water is one of the products.

Assertion (A): Colour of KMnO_4 disappears when dihydrogen gas is bubbled through it. Reason (R) :Dihydrogen gas is highly inflammable.

Assertion (A) : Colloidal solution are stable but the colloidal particles do not settle down. Reason (R): Brownian movement counters the force of gravity actively on colloidal particles.

Assertion (A): Chloroform vapours can be used as an anaesthetie. Reason (R): Chloroform vapours depresses the central nervous system and cause unconsciousness.

Assertion (A): Chlorine water has antibacterial action and also used as bleach. Reason (R): Chlorine reacts with water to give hydrochloric acid and hypochlorous acid which are found in many applications.

Assertion (A): Chloro benzene is prepared by Sandmayer reaction or Gattermann reaction using benzene diazonium chloride. Reason (R): When aqueous solution of benzene diazonium chloride is warmed with Cu_(2)Cl_(2) in HCl give chloro benzene.

Assertion (A): Chemical equilibrium is in a state of dynamic equilibrium. Reason (R): At equilibrium the forward and backward reactions are proceeding at the same rate and no macroscopic change is observed.

Assertion (A) : CH_(4) , CO_(2) has value of Z (compressibility factor )less than one a 0^(@) C . Reason (R) : For every molecule there are three rotational degree of freedom .

Assertion (A) :CH_(3) -BH - overset(+) CH_(2)connot show resonance. Reason (R) : Boron and carbocation both are electron defficient species .

Assertion (A) :CH_(3)-CH-CH_(3) has 6 hyper-conjugative hydrogens. WhileCH_(3)-CH-CH_(2)-CH_(3)has 5 hyper-conjugative hydrogens. Reason (R):CH_(3) -overset(+)CH -CH_(3) is more stable than CH_(3) - overset(+)CH -CH_(2) -CH_(3)

Assertion: A catalyst is more effective in finely divided form. Reason: Finely divided form the more surface area.

Assertion : A catalyst does no alter the equilibrium constant of a reaction. Reason : The catalyst forms a complex with the reactant and provides an alternate path with lowe energy of in activation for the reaction. The forward and reverse reaction are affected to the same extent.

Assertion (A): Carbon halogen bond is a polar bond. Reason (R): Halogens are more elective negative than carbon.

Assertion (A) : Carbon dioxide is one of the important greenhouse gases.Reason (R) : It is largely produced by respiratory function of animals and plants.

Assertion (A) : Carbon dioxide is one of the important greenhouse gases Reason (R): It is largely produced by respiratory function of animals and plants

Assertion (A) Calgon is used for removingCA^(2+) and Mg^(2+) ions from hard water. Reason (R ) Calgon forms precipitates with Ca^(2+) and Mg^(2+)

Assertion (A): Carbon cannot form ionic bond. Reason (R): It is not possible for the carbon to form either C^(4+) or C^(4-) ions, as it requires large amount of energy.

Assertion (A) :C_(2) H_(5) - overset(+)CH-C_(2) H_(5)is more stable thenCH_(3) - overset (+)CH -CH_(3) Reason (R) : Positive inductive effective ofC_(2) H_(5) -group is less thanCH_(3)- group .

Assertion (A) :BrCl + Ican form to 6 different geometrical isomers . Reason (R) : Each one structure is geometrical isomere of other five structures .

Assertion (A) : Boronhas smallerfirstionisation enthalpy than beryllium Reason( R ) :The penetrationof a 2s electron to thenucleusis more than the2pelectronhence 2p- electronis moreshieldedby the innercore ofelectrons than 2selectrons .

Assertion (A) : Boron has a smaller first ionisation enthalpy than beryllium Reason (R): The penetration of a 2s electron to the nucleus is more than the 2p electron hence 2p electron is more shielded by the inner core of electrons than the 2s electrons.

Assertion (A) : Boric acid behaves as a weak monobasic acid. Reason (R) : Boric acid contains H-bonds in its structure.

Assertion (A) : Boron always forms covalent bond. Reason (R) :The small size of B^(3+) favours formation of covalent bond.

Assertion (A) : Bohr's orbits are also called stationary states. Reason (R ) : Electrons are stationary is an orbit.

Assertion (A) : B(OH)_(3) is weakly basic. Reason (R) : B-O bonds can be broken easily.

Assertion (A) : B(OH)_(3) is acidic while In(OH)_(3) is basic. Reason (R) : B(OH)_(3) has highly H-bonded net-work structure.

Assertion (A) : Black body is an ideal body that emits and absorbs radiations of all frequencies. Reason (R) : The frequency of radiation emitted by a body goes from a lower frequency to higher frequency with an increase in temperature.

Assertion (A): Black body is an ideal body that emits and absorbs radiations of all frequencies Reason (R) : The frequency of radiation emitted by a body goes from a lower frequency to higher frequency with an increase in temperature

Assertion (A) : Beryllium carbonate is unstable and decomposes to give beryllium oxide and carbon dioxide . Reason (R) : Beryllium carbonate is unstable and decomposes to give beryllium oxide and carbon dioxide .

Assertion (A) : Beryllium carbonate is kept in the atmosphere of carbon dioxide. Reason (R) : Beryllium carbonate is unstable and decomposes to give beryllium oxide and carbon dioxide.

Assertion (A): B_(2), O_(2), NO are paramagnetic in nature.

Assertion (A): Atomic radius tends to decrease across a period.Reason (R): As we move from left to right along a period, the valence electrons are added to the same shell, nuclear charge increases and atomic radius decreases.

Assertion (A) : Atmosphere contains small amount of poisonous gases but they are preferably adsorbed on activated charcoal. Reason (R): On a particular adsorbent, the more strongly adsorbable adsorbate adsorbs to a greater extent than its partial pressure indicates.

Assertion (A) : At critical temperature, liquid passes into gaseous state imperceptibly and continuously. Reason (R ) : The density of liquid and gaseous phase is equal at critical temperature.

Assertion (A) : At critical temperature liquid passes into gaseous state imperceptibly and continuously.Reason (R ) : The density of liquid and gaseous phase is equal to critical temperature.

Assertion (A) : At constant temperature, pV vs V plot for real gases is not a straight line.Reason (R ) : At high pressure all gases have Z gt 1 but at intermediate pressure most gases have Z lt 1.

Assertion (A): At a given temperature 1 mole of any gas has same kinetic energy. Reason (R):Kinetic energy = (3/2)RT (for 1mole of gas).

Assertion (A) : At constant temperature, pV vs. V plot for real gases is not straight line. Reason (R ) : At high pressure, all gases have Z gt 1 but at intermediate pressure, most gases have Z lt 1.

Assertion (A) : Aqueous solutions of ZnSO_4is neutral. Reason ( R ):Salt of strong base and weak acid undergoes anionic hydrolysis.

Assertion (A) : Aqueous solution of Na_2CO_3show p^(H) gt 7. Reason ( R ):Salt of strong base and weak acid undergoes anionic hydrolysis.

Assertion (A): Aqueous solution of ammonium acetate is neutral Reason(R): Dissociation constants of NH_(4),OH(K_(6)) and that of CH_(3),COOH (K_(a)) are nearly equal.

Assertion (A) : Aqueous solution of ammonium carbonate is basic. Reason (R) : Acidic/basic nature of a salt solution ofa salt of weak acid and weak base depends on K_(a) and K_(b) value of the acid and the base forming it.