52671 + Interview Questions in Chemistry in Class 11

1.	Assertion (A): Aqueous solution of ammonium carbonate is basic. Reason (R) : Acidic/basic nature of a salt solution of a 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 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. Solution :Both assertion and reason are true and reason is the correct explanation of assertion. `{:((NH_4)_2CO_3 to , 2overset+NH_4+,CO_3^(2-)),(""2H_2O to, 2OH^(-) + , 2H^+),(,darr,darr),(,NH_4OH,N_2CO_3),(,"WEAK base","weak acid"):}` `K_b` of `NH_4OH gt K_a ` of `H_2CO_3` so solution is BASIC `K_a` of `H_2CO_3 gt K_b` of `NH_4OH` , the solution is ACIDIC.

Discussion

2.	Assertion (A): Antacids are used as medicines for treating heartbum and acidity. Reason (R): Gastric acid produced in stomach is hydrochloric acid. Antacid is used to treat acidity because they contain bases such as magnesium hydroxide and Aluminium hydroxide.
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

3.	Assertion (A) : Angular momentum of an electron in an atom is quantized . Reason (R ) : In an atom only those orbits are permitted in which angular momentum of the electron is natural number multiple of h/(2pi).
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 :A

Discussion

4.	Assertion (A) :Angular momentum of 1s,2s,3s, ets allhave spectrical shape Reason (R ) : 1s,2s,3s, ets allhave spectrical shape
Answer» If both (A) and (R ) CORRECT and (R ) is the CORRECTEXPLANATION for (A) If both (A) and (R ) correct and (R ) is the correctexplanation for (A) If (A) is correct but (R ) is incorrect If (A) is incorrect but (R ) is correct SOLUTION :REASON is not the correct explanation

Discussion

5.	Assertion (A) : An aqueous solution of ammonium acetate can act as a buffer. Reason (R) : Acetic acid is a weak acid and NH_(4) OH is a weak base.
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. Solution :Correct explanation. Ammonium acetate is a salt of weak ACID and weak base.

Discussion

6.	Assertion (A): An aqueous solution of ammonium acetate can act as a buffer. Reason (R) : Acetic acid is a weak acid and NH_4OH is a weak base.
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. Solution :Both assertion and reason are true but reason is not correct explanation of assertion. AMMONIUM acetate is a salt of weak acid `(CH_3COOH)` and weak base `(NH_4OH)`.

Discussion

7.	Assertion (A) : Among the two O-H bonds in H_(2)O molecule, the energy, required to break the first O-H bond and the other O-H bond .
Answer» A and R both are correct, and R is the correct ecplanation of A. A and R both are correct, But R is not the correct ecplanation of A . A is true but R is FALSE . A and R both are false. Solution :Correct A : Thebond ENTHALPIES of the two O-H bonds in H-O-H are not equal . Correct R : This is because ELECTRONIC environment AROUND O is not same after breakage of ONE O-H bond.

Discussion

8.	Assertion (A) : Among the two O - H bonds in H_(2)Omolecule, the energy required to break the first O - H bond and the other O - H bond is the same. Reason (R) : This is because the electronic environment around oxygen is the same even after breakage of one O - H bond.
Answer» A and R both are CORRECT, and R is correct EXPLANATION of A. A and R both are correct, but R is not the correct explanation of A. A is true but R is false. A and R both are false. Solution :Correct assertion : The bond ENTHALPIES of the two O-H bonds in H-O-H are not equal. Correct REASON : This is because electronic ENVIRONMENT around O is not same after breakage of one 0-H bond.

Discussion

9.	Assertion (A) : Among isomeric pentanes, 2,2-dimethyl-pentane has highest boiling point. Reason (R) : Branching does not affect the boiling point.
Answer» Both A and R are correct and R is the correct explanation of A. Both A and R are correct and R is not the correct explanation of A. Both A and R are not correct. A is not correct but R is correct. Solution :Among ISOMERIC pentanes 2,2-dimethyl PENTANE has lowest boiling POINT and on branching boiling point DECREASES.

Discussion

10.	Assertion (A): Among isomeric halides, the boiling point decreases with increase in branching in alkyl group. Reason (R): With the increase in branching, the molecule attains spherical shape with less surface area and less forces of interaction.
Answer» Both (A) and (R) are CORRECT and (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 not the correct explanation of (A).

Discussion

11.	Assertion (A) : Among halogens fluorine is the best oxidant. Reason ( R): Fluorine is the most electronegative atom.
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. Both A and R are false. Solution :`F_(2)` is the OXIDANT because it has the HIGHEST `E^(@)` value.

Discussion

12.	Assertion (A): Among halogens fluorine is the best oxidant. Reason ( R) : Fluorine is the most electronegative atom.
Answer» Both A and R are true and R explains A Both A and R are true but R does not EXPLIAN A A is true but R is FALSE Both A and R is false. Answer :A::B::D

Discussion

13.	Assertion (A) : among halogensfluorine is the best oxidant Reason (R ) : Fluorine is the most electronegativeatom
Answer» both a and r are ture and r is the correct explantion of a both a and r are ture but r is not the correct xplanatio of a a is true but r is FLASE both a nad r are flase Solution :correct EXPLANATION AMONG halogens `F_(2)` is the best oxidant because it has the highest `E^(@)` VALUE

Discussion

14.	Assertion (A) : Al(OH)_(3) is amphoteric in nature. Reason (R) : Al-O and O-H bonds can be broken with equal ease in Al(OH)_(3).
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 :Both ASSERTION and reason are correct.

Discussion

15.	Assertion (A): All the carbon atoms in H_(2)C = C = CH_(2) are sp^(2) hybridised. Reason (R) : In this molecule all the carbon atoms are attached to each other by double bonds.
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 :Correct (A). In `CH_(2) = C = CH`, the central carbon is sp-hybridizedwhile the TERMINAL carbon atoms are `sp^(2)`-hybridized.

Discussion

16.	Assertion (A): Allyl carbanion(CH_(2) = CH- CH_(2))is more stable thanCH_(2)-NO_(2) Reason (R) : OnCH_(2)-NO_(2), only -I effect of No group is present while is allyl carbanion resonance is present
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 true statement but R is FALSE Both A and R are false SOLUTION :N/A

Discussion

17.	Assertion (A): All the carbon atoms in H_(2)C = C = CH_(2) are sp^(2)-hybridised Reason (R ): In this molecule all the carbon atoms are attached to each other by double bonds.
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 : If four `SIGMA`-bond with C then it is `sp^(3)` carbon. If three `sigma`-bond with C then it is `sp^(2)` carbon. And if two `sigma`-bond with C then it is sp carbon. So, Assertion (A) is not correct Because (R ) Reason is correct. In these example all carbon are attached by DOUBLE bond with each other `underset("Between double bond")(overset(1)(C )H_(2) underset(underset(C_(1)-C_(2))(darr))(=) overset(2)(C )H underset(underset(underset(C_(2) and C_(3))("Double bond between"))(darr))(=) overset(3)(C )H_(2)`

Discussion

18.	Assertion (A) : All molecules in a gas have some speed . Reason (R) : Gas contains molecules of different size and shape .
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 . Solution :(All molecule of a GAS have different speed . Therefore , they move by its ownspeed

Discussion

19.	Assertion (A): All isotopes of a given element show the same type of chemical behaviour. Reason (R) : The chemical properties of an atom are controlled by the number of electrons in the atom
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 :All ISOTOPES of any element have same ATOMIC NUMBER and hence same number of protons and electrons. As electrons take part in a chemical reaction, atoms having same having same number of electrons show same type of chemical BEHAVIOUR

Discussion

20.	Assertion (A) : All isotopes of a given element show the same type of chemical behaviour. Reason (R) : The chemical properties of an atom are controlled by the number of electrons in the atom.
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 explanation of A. A is true and R is false Both A and R are false Solution :Both ASSERTION and reason are true and reason is the correct explanation of assertion. Isotopes have the sam e atom ic num BER i.e ., same number of electrons which are responsible for their chemical behaviour. So, these EXHIBIT similar chemical properties.

Discussion

21.	Assertion (A): Alkali metal salts with conc.HCl on heating gives characteristic coloured flame. Reason (R): The heat in the flame excited the valence electron to higher energy level and when it drops back, the excess energy emitted as light in the visible region gives colour
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 Answer :B

Discussion

22.	Assertion (A) : Al forms [AlF_(6)]^(3-) ions but B does not form [BF_(6)]^(3-) ions. Reason (R) :B does not react with F_(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 FALSE A is false but R is true Solution :Reason. DUE to non-availability of d-subshell in the valence shell of B, it cannot expand its octet.

Discussion

23.	Assertion (A) : Alcohols are dehydrated to hydrocarbons in the presence of acidic zeolites. Reason (R) : Zeolites are porous catalyst.
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 a correct explanation of A. A is true but R is FALSE. A is false but R is true. Answer :B

Discussion

24.	Assertion (A): addition of HCN in alkene is a type of electrophilic substitution reaction. Reason (R): in first step ,H_(3)O^(+) attacks on double bond .
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

25.	Assetion(A): Acetylene on additionalpolymerization gives benzene. Reason(R): The empirical formulae of acetylene and benzene are same The correct answer is
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 :`underset("ACETYLENE")(3C_(2)H_(2))underset("trimerisation")overset("Red hot metallic tube")rarrunderset("Benzene")(C_(6)H_(6))` Empirical FORMULA acetylene = CH Empirical formula of benzene = CH

Discussion

26.	Assertion (A) : A standard solution of required concentration can be prepared by dissolving a required amount of a solute in a suitable amount of solvent Reason ® : A standard solution is a solution whose concentration is accurately known.
Answer» Both (A) and ® are TRUE ® is the CORRECT explanation of (A) Both (A) and ® are TURE and ® is not the correct explanation of (A) (A) true but ® false Both (A) and ® are false ANSWER :A

Discussion

27.	Assertion (A) : A yellow precipitate is formed when ethanol is refluxedwith iodine and sodium carbonate. Reason (R) :Ethanol reacts with sodium carbonate yellow coloured ethyl carbonate.
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 a correct explanation of A. A is true but R is false. A is false but R is true. Answer :C

Discussion

28.	Assertion (A) : A pure solid always has the same concentration at a given temperature. Reason (R) : It does not expand to fill its container.
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 :A

Discussion

29.	Assertion (A) : A sol of As_(2)S_(3) prepared by the action of H_(2)S on As_(2)O_(3) is negatively charged. Reason (R): It is due to the adsorption of H^(+) ions on the surface of the colloidal particle and S^(2-) ions in the diffused layer.
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 :C

Discussion

30.	Assertion (A) : A solution containing a mixture of acetic acid and sodium acetate maintains a constant value of pH on addition of small amounts of acid or alkali. Reason (R) : A solution containing a mixture of acetic acid and sodium acetate acts as a buffer solution around pH 4.75 .
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

31.	Assertion (A): A solution containing a mixture of acetic acid and sodium acetate maintains a constant value of pH on addition of small amounts of acid or alkali.Reason (R) : A solution containing a mixture of acetic acid and sodium acetate acts as a buffer solution around pH 4.75.
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. SOLUTION :Both assertion and reason are correct and reason is correct explanation of assertion. A solution CONTAINING a mixture of acetic acid and the SODIUM acetate acts as a buffer solution as it maintains a constant value of pH (= 4.75) and its pH is not affected on addition of small amounts of acid or alkali.

Discussion

32.	Assertion (A): A mixture of ammonia and hydrogen peroxide can bleach the human hair to golden colour.Reason (R): Ammonia solution is basic in nature
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. Answer :B

Discussion

33.	Assertion (A) : A lyophilic colloidal sol is more stable than a lyophobic sol. Reason (R): A lyophilic sol is solvated to a much greater extent in comparision to lyophobic sol.
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 :B

Discussion

34.	Assertion (A): A liquid crystallizes into a solid and accompanied by decrease in entropy Reason (R): In crystals molecules are organised in an ordered manner.
Answer» both ASSERTION and Reason are true and Reason is the correct explanation of Assertion both Assertion and Reason are true and Reason is NOTCORRECT explanation of Assertion both Assertion and Reason are FALSE Assertion is false but Reason is true Answer :A

Discussion

35.	Assertion (A) : A liquid crystallises into a solid and is accompanied by decrease in entropy. Reason (R) : In crystals, molecules organise in an ordered manner.
Answer» ANSWER :(a)

Discussion

36.	Assertion : A 30% solution of H_(2)O_(2) is marketed as '100 volume' hydrogen perocide. Reason : 1 L of 30 % H_(2)O_(2) will give 100 mL of oxygen at STP.
Answer» If both assertion and reason are true and reason is the CORRECT explanation of assertion. If both assertion and reason are true but reason is not the correct explanation of assertion. If assertion is true but reason is false. If both assertion and reason are false. Solution :One MILLILITRE of 30% `H_(2)O_(2)` solution will give 100 mL of oxygen at STP.

Discussion

37.	Assertion (A) 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(10)4s^(1) is the configuration of an alkali metal.Reason (A) Alkali metal contain one electron in the s-subshell of valence shell.
Answer» Solution :The given configuration is that of COPPER (Group II) and not of ALKALI metal.

Discussion

38.	Assertion (A) : 1 c.c. of Nitrogen at STP contains 2.69xx10^(19) molecules. Reason (R ) : Molar volume of an ideal gas at STP contains Avogadro number of molecules.
Answer» SOLUTION :Loschmidt NUMBER.

Discussion

39.	Assertion (A ): Theorbitalcannothave morethan twoelectrons > Reason (R )Twoelectronsin anorbitalcreate oppositemagneticfield . Thecorrectchoiceis
Answer» both(A ) and (R )are TRUE(R ) is the correctexplantionof (A ) both (A)and (R )are truebut (R )is not thecorrectexplanationof (A ) (A ) istruebut (R )is nottrue (A )is not truebut (R ) is true ANSWER :B

Discussion

40.	Assertion (A ) : Theprobabilityof findingan electronin asmallvolumearounda point(x,y,z )at adiatance r from the nucleusisproportionalto . reason (R ) :subatomicparticlehave bothwaveandparticlenature . The correct choiceis
Answer» Both(A ) and (R )are TRUEAND (R )is thecorrectexplanation of (A) Both(A )and (R )are truebut (R )is notthecorrectexplanationof (A ) istruebut (R )is nottrue (A)is nottruebut (R ) is TRUE ANSWER :B

Discussion

41.	Assertion (A ): The19^(th)electronin potassiumatom enetersinto4s-orbitalandnotthe 3d-orbital Reason (R: (n + l)ruleis followedfordeterminingthe orbitalof the lowestenergystate. Thecorrectchoice is
Answer» Both (A)and (R ) are TRUE and (R )is thecorrectexplanation of(A ) both (A)and (R )are truebut (R )is not thecorrectexplanationof (A ) (A) istruebut (R ) ISNOT true (A )is not truebut (R ) is true ANSWER :A

Discussion

42.	Assertion( A ) : If BOD level of water in a reservoir is more than 5 ppm it is highly polluted Reason ( R ) : High biological oxygen demand means high activity of bacteria in water
Answer» Both ( A) and R are CORRECT and ( R ) is the correct EXPLANATION of ( A ) Both ( A ) and R are correct and (R ) is not the correct explanation of ( A) Both ( A ) and R are not correct (A) is correct but ( R ) is not correct ANSWER :d

Discussion

43.	Assertion: 65.38 g of Zn when treated with excess of dilute H_2SO_4, will always form 22.4 L of H_2 at S.T.P. Reason: The yield of a product is always in accordance with the stoichiometry of the reaction.
Answer» If both ASSERTION and REASON are CORRECT and Reason is the CORRECT EXPLANATION of the Assertion. If both Assertion and Reason are CORRECT but Reason is not the CORRECT explanation of the Assertion. If Assertion is CORRECT but Reason is INCORRECT If Assertion is INCORRECT but Reason is CORRECT. Answer :B

Discussion

44.	Assertion : 5 M HCl solution is diluted 10 times, its molarity becomes 50. Reason : On dilution, molarity of the solution decreases.
Answer» If both ASSERTION and REASON are CORRECT, and Reason is the correct EXPLANATION of Assertion. If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion. If Assertion is correct, but Reason is INCORRECT. If Assertion is incorrect, but Reason is correct. Solution :N//A

Discussion

45.	Assertion : 4n+1 series is designated as Neptunium series. Reason : The fourth series is not naturally occuring and Neptunium -237 is the longest -lived member of the series.
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

46.	Assertion : 3H_(2_((g))) +N_(2_((g)))rarr2NH_(3_((g))) is exothermic. Reason : The process passes into equilibrium state when DeltaG_(T,P) becomes zero.
Answer» Both assertion and reason are TRUE and reason is the CORRECT EXPLANATION of the assertion Both assertion and reason are true and reason is not the correct explanation of the assertion Assertion is true but reason are false Both assertion and reason are false. Answer :B

Discussion

47.	Assertion: 2,2-Dimethylbutane does not have any tertiary carbon atom. Reason: Tertiary carbon atom is attached to three carbon atoms.
Answer» If both ASSERTION and RESON are true and reason is the CORRECT EXPLANATION of assertion If both assertion and reason are true but reason is not the correct explanation of assertion. If assertion is true but reason is false. If both assertion and reason are false. Answer :A

Discussion

48.	Assertion : 22 carat gold is a mixture Reason :A compound has fixed composition of the elements present in it.
Answer» If both assertion and REASON are correct and reason is correct explanation 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 both assertion and reason are incorrect Solution :22 carat GOLD is a homogeneous mixture un which gold is mixed with small AMOUNT of COPPER or silver.

Discussion

49.	Assertion. 2-Butyne on controlled hydrogenation with Pd//CaCO_3 in presence of PbO gives cis-2-butene Reason. Hydrogenation occurs at the surfaces of metal containing adsorbed hydrogen.
Answer» If both ASSERTION and REASON are TRUE, and reason is the true EXPLANATION of the assertion. If both assertion and reason are true, but reason is not the true explanation of the assertion. If assertion is true, but reason is false. If both assertion and reason are false Answer :A

Discussion

50.	Assertioin: Silicate minerals are seldon used for hte extraction of a metal. Reason: Silicate minerals are very rare.
Answer» Both A and R ar true and R is the CORRECT explanation of A Both A and R are true but R is not a correct explanation ofA A is true but R is false A is false but R is true Solution :Silicate minerals are very COMMON, however due to their less reactivity and high cost of extraction of METALS from them, they are SELDOM used as ores.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

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

Assertion (A): Antacids are used as medicines for treating heartbum and acidity. Reason (R): Gastric acid produced in stomach is hydrochloric acid. Antacid is used to treat acidity because they contain bases such as magnesium hydroxide and Aluminium hydroxide.

Assertion (A) : Angular momentum of an electron in an atom is quantized . Reason (R ) : In an atom only those orbits are permitted in which angular momentum of the electron is natural number multiple of h/(2pi).

Assertion (A) :Angular momentum of 1s,2s,3s, ets allhave spectrical shape Reason (R ) : 1s,2s,3s, ets allhave spectrical shape

Assertion (A) : An aqueous solution of ammonium acetate can act as a buffer. Reason (R) : Acetic acid is a weak acid and NH_(4) OH is a weak base.

Assertion (A): An aqueous solution of ammonium acetate can act as a buffer. Reason (R) : Acetic acid is a weak acid and NH_4OH is a weak base.

Assertion (A) : Among the two O-H bonds in H_(2)O molecule, the energy, required to break the first O-H bond and the other O-H bond .

Assertion (A) : Among the two O - H bonds in H_(2)Omolecule, the energy required to break the first O - H bond and the other O - H bond is the same. Reason (R) : This is because the electronic environment around oxygen is the same even after breakage of one O - H bond.

Assertion (A) : Among isomeric pentanes, 2,2-dimethyl-pentane has highest boiling point. Reason (R) : Branching does not affect the boiling point.

Assertion (A): Among isomeric halides, the boiling point decreases with increase in branching in alkyl group. Reason (R): With the increase in branching, the molecule attains spherical shape with less surface area and less forces of interaction.

Assertion (A) : Among halogens fluorine is the best oxidant. Reason ( R): Fluorine is the most electronegative atom.

Assertion (A): Among halogens fluorine is the best oxidant. Reason ( R) : Fluorine is the most electronegative atom.

Assertion (A) : among halogensfluorine is the best oxidant Reason (R ) : Fluorine is the most electronegativeatom

Assertion (A) : Al(OH)_(3) is amphoteric in nature. Reason (R) : Al-O and O-H bonds can be broken with equal ease in Al(OH)_(3).

Assertion (A): All the carbon atoms in H_(2)C = C = CH_(2) are sp^(2) hybridised. Reason (R) : In this molecule all the carbon atoms are attached to each other by double bonds.

Assertion (A): Allyl carbanion(CH_(2) = CH- CH_(2))is more stable thanCH_(2)-NO_(2) Reason (R) : OnCH_(2)-NO_(2), only -I effect of No group is present while is allyl carbanion resonance is present

Assertion (A): All the carbon atoms in H_(2)C = C = CH_(2) are sp^(2)-hybridised Reason (R ): In this molecule all the carbon atoms are attached to each other by double bonds.

Assertion (A) : All molecules in a gas have some speed . Reason (R) : Gas contains molecules of different size and shape .

Assertion (A): All isotopes of a given element show the same type of chemical behaviour. Reason (R) : The chemical properties of an atom are controlled by the number of electrons in the atom

Assertion (A) : All isotopes of a given element show the same type of chemical behaviour. Reason (R) : The chemical properties of an atom are controlled by the number of electrons in the atom.

Assertion (A): Alkali metal salts with conc.HCl on heating gives characteristic coloured flame. Reason (R): The heat in the flame excited the valence electron to higher energy level and when it drops back, the excess energy emitted as light in the visible region gives colour

Assertion (A) : Al forms [AlF_(6)]^(3-) ions but B does not form [BF_(6)]^(3-) ions. Reason (R) :B does not react with F_(2).

Assertion (A) : Alcohols are dehydrated to hydrocarbons in the presence of acidic zeolites. Reason (R) : Zeolites are porous catalyst.

Assertion (A): addition of HCN in alkene is a type of electrophilic substitution reaction. Reason (R): in first step ,H_(3)O^(+) attacks on double bond .

Assetion(A): Acetylene on additionalpolymerization gives benzene. Reason(R): The empirical formulae of acetylene and benzene are same The correct answer is

Assertion (A) : A standard solution of required concentration can be prepared by dissolving a required amount of a solute in a suitable amount of solvent Reason ® : A standard solution is a solution whose concentration is accurately known.

Assertion (A) : A yellow precipitate is formed when ethanol is refluxedwith iodine and sodium carbonate. Reason (R) :Ethanol reacts with sodium carbonate yellow coloured ethyl carbonate.

Assertion (A) : A pure solid always has the same concentration at a given temperature. Reason (R) : It does not expand to fill its container.

Assertion (A) : A sol of As_(2)S_(3) prepared by the action of H_(2)S on As_(2)O_(3) is negatively charged. Reason (R): It is due to the adsorption of H^(+) ions on the surface of the colloidal particle and S^(2-) ions in the diffused layer.

Assertion (A) : A solution containing a mixture of acetic acid and sodium acetate maintains a constant value of pH on addition of small amounts of acid or alkali. Reason (R) : A solution containing a mixture of acetic acid and sodium acetate acts as a buffer solution around pH 4.75 .

Assertion (A): A solution containing a mixture of acetic acid and sodium acetate maintains a constant value of pH on addition of small amounts of acid or alkali.Reason (R) : A solution containing a mixture of acetic acid and sodium acetate acts as a buffer solution around pH 4.75.

Assertion (A): A mixture of ammonia and hydrogen peroxide can bleach the human hair to golden colour.Reason (R): Ammonia solution is basic in nature

Assertion (A) : A lyophilic colloidal sol is more stable than a lyophobic sol. Reason (R): A lyophilic sol is solvated to a much greater extent in comparision to lyophobic sol.

Assertion (A): A liquid crystallizes into a solid and accompanied by decrease in entropy Reason (R): In crystals molecules are organised in an ordered manner.

Assertion (A) : A liquid crystallises into a solid and is accompanied by decrease in entropy. Reason (R) : In crystals, molecules organise in an ordered manner.

Assertion : A 30% solution of H_(2)O_(2) is marketed as '100 volume' hydrogen perocide. Reason : 1 L of 30 % H_(2)O_(2) will give 100 mL of oxygen at STP.

Assertion (A) 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(10)4s^(1) is the configuration of an alkali metal.Reason (A) Alkali metal contain one electron in the s-subshell of valence shell.

Assertion (A) : 1 c.c. of Nitrogen at STP contains 2.69xx10^(19) molecules. Reason (R ) : Molar volume of an ideal gas at STP contains Avogadro number of molecules.

Assertion (A ): Theorbitalcannothave morethan twoelectrons > Reason (R )Twoelectronsin anorbitalcreate oppositemagneticfield . Thecorrectchoiceis

Assertion (A ) : Theprobabilityof findingan electronin asmallvolumearounda point(x,y,z )at adiatance r from the nucleusisproportionalto . reason (R ) :subatomicparticlehave bothwaveandparticlenature . The correct choiceis

Assertion (A ): The19^(th)electronin potassiumatom enetersinto4s-orbitalandnotthe 3d-orbital Reason (R: (n + l)ruleis followedfordeterminingthe orbitalof the lowestenergystate. Thecorrectchoice is

Assertion( A ) : If BOD level of water in a reservoir is more than 5 ppm it is highly polluted Reason ( R ) : High biological oxygen demand means high activity of bacteria in water

Assertion: 65.38 g of Zn when treated with excess of dilute H_2SO_4, will always form 22.4 L of H_2 at S.T.P. Reason: The yield of a product is always in accordance with the stoichiometry of the reaction.

Assertion : 5 M HCl solution is diluted 10 times, its molarity becomes 50. Reason : On dilution, molarity of the solution decreases.

Assertion : 4n+1 series is designated as Neptunium series. Reason : The fourth series is not naturally occuring and Neptunium -237 is the longest -lived member of the series.

Assertion : 3H_(2_((g))) +N_(2_((g)))rarr2NH_(3_((g))) is exothermic. Reason : The process passes into equilibrium state when DeltaG_(T,P) becomes zero.

Assertion: 2,2-Dimethylbutane does not have any tertiary carbon atom. Reason: Tertiary carbon atom is attached to three carbon atoms.

Assertion : 22 carat gold is a mixture Reason :A compound has fixed composition of the elements present in it.

Assertion. 2-Butyne on controlled hydrogenation with Pd//CaCO_3 in presence of PbO gives cis-2-butene Reason. Hydrogenation occurs at the surfaces of metal containing adsorbed hydrogen.

Assertioin: Silicate minerals are seldon used for hte extraction of a metal. Reason: Silicate minerals are very rare.