52671 + Interview Questions in Chemistry in Class 11

1.	Assertion (A): If aluminium atom s replace a few silicon atoms in three dimensional network of silicon dioxide, the overall structure acquriesa negative charge. Reason(R): Aluminium is trivalent while silicon is tetravalent.
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 :Assertionis not correct but reason is correct. Aluminium is trivalent whereas silicon is tetravalent. If aluminium ATOM replaces a few silicon ATOMS in three DIMENSIONAL network of silicon dioxide, the overall structure acquires neutrally.

Discussion

2.	Assertion (A): Hydrogen reacts faster with halogens than deuterium. Reason (R) : The activation energy of hydrogen is less than that of deuterium.
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 :A

Discussion

3.	Assertion (A): Hydrogen peroxide is used in water treatment to oxidise pollutants. Reason (R): The oxidising ability and harmless nature of H_(2)O_(2), is mainly used in many applications,
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 :B

Discussion

4.	Assertion (A) Hydrogen peroxide forms only one series of salts called peroxides. Reason (R ) Hydrogen peroxide molecule has only one replaceable hydrogen 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 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. Hydrogen PEROXIDE forms two series of salts CALLED hydroperoxides and peroxides. Correct Reason. Hydrogen peroxide molecule has two replaceable hydrogen atoms.

Discussion

5.	Assertion (A): Hydrogen is placed in group-I along with alkali metals. Reason (R): In most of the compounds of hydrogen, exists in the oxidation state.
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

6.	Assertion (A) :HNO_3 is not a Bronsted acid in CHCl_3 Reason ( R ) :CHCl_3 is an example of aprotic solvent .
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 :` CHCl_3` is aprotic

Discussion

7.	Assertion (A): H_(2), Li_(2), C_(2), N_(2) are diamagnetic. Reason (R): All have no unpaired electrons and so they are diamagnetic.
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 and (R) is the correct explanation of (A).

Discussion

8.	Assertion (A): hep is repersented as abababab ………….. Reason ® : the atoms in thetwo 'a' layers occupy the sites fo the unit cell of hexagonal bravis lattice , the atoms with in the cell ( the b layer) donot occupy sites .
Answer» if both (A) and ® are correct , and ® is correct explanartion of (A if both (A) and® are correct , but ® is nmot the correct explanation of if (A) is correct , but ® is INCORRECT. if both (A) and ® are icorrect . ANSWER :A

Discussion

9.	Assertion (A): Heat of neutralization of HClO_(4) with NaOH is same as that of HCl with NaOH Reason (R ): Both HCL and HClO_(4) are strong acids
Answer» A and R are TRUE, R explains A A and R are true, R does not EXPLAIN A A is true, but R is false A is false, but R is true Solution :`DELTA H_("neutralization")` is same for all SA + SB

Discussion

10.	(A): HCl is not acidic in benzene. (R): Benzene does not accept protons
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) Both (A) and ( R )are true and ( R )is not the correct explanation of (A) (A) is true but ( R )is false Solution :BENZENE is aprotic

Discussion

11.	Assertion (A): Haloarenes do not undergo nucleophilic substitution reactions readily. Reason (R): The C - X bond in aryl halides is short and stronger and also the aromatic ringis a centre of high electron density.
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

12.	Assertion (A): Haloarenes are insoluble in water. Reason (R): Haloarenes are able to form hydrogen bonds with water.
Answer» Both (A) and (R) are CORRECT but (R) is the correct EXPLANATION of (A). both (A) and (R) are correct and (R) is not the correct explanation of (A). (A) is correct but (R) is WRONG. (A) is wrong but (R) is correct Solution : (A) is correct but (R) is wrong.

Discussion

13.	Assertion (A): Haloalkanes have higher boiling point and melting point than the parent alkanes having the same number of carbon. Reason (R): The intermolecular forces of atraction and dipole-dipole interactions arestronger in haloalkanes.
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

14.	Assertion (A) : H_(3)BO_(3) is a tribasic weak acid. Reason (R) : B is a typical non-metal.
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 :`H_(3)BO_(3)` is a weak monobasic ACID. `B(OH)_(3)+H_(2)O HARR [B(OH)_(4)]^(-)+H^(+)`

Discussion

15.	Assertion (A): Smooth muscles do not show straitions. Reason (R): They are voluntary muscles.
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 and (R) is the correct explanation of (A).

Discussion

16.	Assertion (A): H_2 and O_2 have same R.M.S. velocity at the same temperature. Reason ® : R.M.S. velocity of a gas molecules is directly proportional to square root its 'T'.
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 :`(U_(H_2))/(U_(O_2)) = SQRT((M_2)/(M_1)) = sqrt((32)/(2)) = 4`.

Discussion

17.	Assertion (A): Greenhouse effect was observed in houses used to grow plants and these are made of green glass Reason (R) : Green house name has been given because glass houses are made of green glass
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 Assertion.GREENHOUSE effect was observed in HOUSES used to grow plants but these are not MADE of green GLASS but transparent glass Correct Reason. Greenhouse name has been given because it was used to grow green plants.

Discussion

18.	Assertion (A): Green house effect was observed in houses used to grow plants and these are made of green glass.Reason (R) : Green house name has been given because glass houses are made of green glass.
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 :In cold COUNTRIES sunlight is less. So, the growth of plants effects. THEREFORE plants are kept in a house made of glass, placed in such a manner, so that sunlight enters the green house, heat up the soil and plants. The warm soil and plants emit infrared radiations. Since. glass is opaque to infrared radiations, it partly REFLECTS and partly absorbs these radiations.

Discussion

19.	Assertion (A) : Generally, ionisation enthalpy increases from left to right in a period. Reason (R) : When successive electrons are added to the orbitals in the same principal quantum level, the shielding effect of inner core of electrons does not increase very much to compensate for the increased attraction of the electron to the nucleus.
Answer» ASSERTION is correct statement and reason is wrong statement. Assertion and reason both are correct STATEMENTS and reason is correct explanation of assertion. Assertion and reason both are wrong statements. Assertion is wrong statement and reason is correct statement. Solution :Ionisation enthalpy increases from left to RIGHT in a period because effective NUCLEAR charge increases and atomic size decreases.

Discussion

20.	Assertion (A) , Generallyionisationenthalpy increases from left to right in aperiod. Reason( R ): Whensuccessive electrons are addedto the orbitals in thesameprincipalquantum leveltheshielding effectof innercore ofelectrons does notincrease verymuch tocompensate fore theincreased attraction of theelectron of thenucleus.
Answer» ASSERTION is correctstatementand reason is wrongstatement. Assertionandreson both arecorrect STATEMENT ANDREASON is CORRECTEXPLANATION of assertion Assertionand reasonboth arewrongstatement . Assertionis wrongstatementand reasoniscorrect statement. Solution :NA

Discussion

21.	Assertion (A) : Gases do not liquefy above their critical temperature even on applying high pressure. Reason (R ) : Above critical temperature, the molecular speed is high and intermolecular attractions cannot hold the molecules together because they escape because of high speed.
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

22.	Assertion (A) : Gases do not liquefy above their critical temperature, even on applying high pressure.Reason (R ) : Above critical temperature, the molecular speed is high and intermolecular attractions cannot hold the molecules together because they escape because of high speed.
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. Gases don.t liquify above their critical temp., even an APPLYING high pressure because above critical temp., the molecular speed is high and INTERMOLECULAR attractions cannot hold the MOLECULES together.

Discussion

23.	Assertion : A free radical is paramagnetic species. Reason : A free radical is formed in homolytic fission of covalent bond.
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 Solution :Correct explanation. Free RADICALS have ODD number of electrons in the valence shell and hence are paramagnetic.

Discussion

24.	Assertion (A) : For any chemical reaction at a particular temperature, the equilibrium constant is fixed and is a characteristicproperty. Reason (R) :Equilibrium constant is independent of temperature.
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 R. Equilibrium constant of a reaction depends upon temperature.

Discussion

25.	Assertion (A) Following reaction proceed better with KF than with NaF. Reasons (A)-C-Cl+MF rarr-F+MClReason (A) K is more reactive than Na.
Answer» Solution :Reason. LARGE CATION STABILISES larger ANION.

Discussion

26.	Assertion (A) : Fluorescein is an adsorption indicator. Reason (R): Fluorescein is a dye.
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

27.	Assertion (A) : Finely divided iron acts as a catalyst in Haber's process of manufacture of ammonia from nitrogen and hydrogen. Reason (R):Chemisorption of the reacting nitrogen and hydrogen gases on the surface of iron takes place.
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

28.	Assertion (A) : First ionization enthalpy of nitrogen is lower than that of oxygen. Reason (R) : Across a period effective nuclear charge decreases Correct answer is,
Answer» Both (A) and (R) are CORRECT and (R) is the correct EXPLANATION of the (A) Both (A) and (R) are correct and (R) is not the correct explanation of the (A) (A) is correct and (R) is incorrect Both (A) and (R) are incorrect Answer :d

Discussion

29.	Assertion (A) : F atom has less negative electron gain enthalpy than Cl atom. Reason (R) : Additional electrons are repelled more effectively by 3p-electrons in Cl atom than by 2p-electrons in F atom.
Answer» Both (A) and (R) are CORRECT and (R) is the correct EXPLANATION of the (A). Both (A) and (R) are correct and (R) is not the correct explanation of the (A). (A) is correct and (R) is INCORRECT. Both (A) and (R) are incorrect. Solution :(A) is correct and (R) is incorrect.

Discussion

30.	Assertion (A) : Excessive use of chlorinated synthetic pesticides causes soil and water pollution. Reason (R) : Such pesticides are nonbiodegradable
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 :Soil and WATER POLLUTION CAUSES by insecticides, pesticides and herbicides. Which are non biodegradable.

Discussion

31.	Assertion (A): Excessive use of chlorinated synthetic pesticides causes soil and water pollution Reason (R) : Such pesticides are non-biodegradable
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 Answer :A

Discussion

32.	Assertion (A): Excessive use of chlorinated pesticide causes soil and water pollution. Reason (R): Such pesticides are non-biodegradable. '
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 Solution :Both (A) and R are correct and (R).is the correct explanation of (A)

Discussion

33.	Assertion (A): Excessive use of chlorinated pesticide causes soil and water pollution. Reason (R): Such pesticides are non-biodegradable
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 Solution :Both (A) and R are correct and (R) is the correct explanation of (A)

Discussion

34.	Assertion (A) : Equilibrium constant of a reaction increases if temperature is increased Reason (R) : The forward reaction becomes faster with increase of temperature.
Answer» If both (A) and (R) are correct, and (R) is the correct EXPLANATION for (A) If both (A) and (R) are correct, but (R) is not the correct explanation of (A) If (A) is correct, but (R) is incorrect If (A) is incorrect, but (R) is correct. Solution :Forward reaction INCREASE with TEMPERATURE only for endothermic reaction, while for exothermic it is reverse.

Discussion

35.	Assertion (A) : Energy of resonance hybrid is equal to the average of energies of all canonical forms. Reason (R) : Resonance hybrid cannot be represented by a single structure.
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. The energy of the resonancehybrid is equal to the SUM of the energies of the various canonical STRUCTURES in proportion of their contribution towards the resonance hybrid.

Discussion

36.	Assertion (A): Energy of resonance hybrid is equal to the average of energies of all canonical forms. Reason (R ): Resonance hybrid cannot be presented by a single structure.
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 : Resonating structure of resonance is ALWAYS more stable than canonical structure. The reason for this is that delocalization of electron TAKE place with RESPECT to maximum stable canonical structure the stability of resonating structure is more because of resonance energy. The canonical FORM which is more stable its proportion in resonance structure is more because of resonance energy. The conical form which is more stable its proportion in resonance structure is more and all canonical forms according to their stability present in resonance structure. The correct statement is the value of resonance energy of resonance structure is equal to the DIFFERENCE in energy between the actual structure and the most stable of the resonatig structure. The different resonance structure contribute to the actual structure in proportion to their stability.

Discussion

37.	Assertion (A) : Energy of resonance hybrid is equal to the average of energies of all canonial forms. Reason (R) : Resonance hybrid cannot be presented by a single structure.
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 ASSERTION : ENERGY of the RESONANCE hybrid is less than the average of energies of all canonical forms.

Discussion

38.	Assertion (A) : Energy of an electron is taken negative. Reason (R ) : Energy of electron at infinity is zero.
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

39.	Assertion: (A): Emprirical formula of ethane is CH_(3) Reason (R): Empirical formula of all alkenes is CH_(2) 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 :Molecular formula of ethane = `C_(2)H_(6)` Empirical formula of ethane =`CH_(3)` General formula of ALKENES = `C_(N)H_(2N)`

Discussion

40.	Assertion (A): Electrophilic addition addition of Br_(2) to alkyne proceeds faster tha hta of alkene. Reason (R): Bromonium ion intermediate of alkene is stable that that of alkyne.
Answer» If both A and R are TRUE and R is the correct explanation of A. If both A and R are true and R is not the correct EXPLANATIO of A. If A is true but R is false If A is false and R is true. Answer :D

Discussion

41.	Assertion (A) :Electrongain enthapy becomes lessnegativeas we godowna group. Reason ( R) :Size of theatom increases on goindown in thegroup in the addedelectronwould befarther from thenucleus.
Answer» Assertionand reasonboth arecorrectstatementbut REASONIS notcorrectexplanationfor ASSERTION. Assertion and reasonboth arecorrectstatementand reasonis correctexplanationfor assertion Assertionandreasonboth arewrongstatement. Assertionis wrongstatementbutreason iscorrectstatement . SOLUTION :NA

Discussion

42.	Assertion (A): Electron gain enthalpy becomes less negative as we go down a group. Reason (R) : Size of the atom increases on going down the group and the added electron would be farther from the nucleus.
Answer» Assertion and REASON both are correct statements and reason is correct EXPLANATION for assertion. Assertion and reason both are wrong statements. Assertion is wrong STATEMENT but reason is correct statement. Solution : Assertion and reason both are correct statements but reason is not correct explanation for assertion.

Discussion

43.	Assertion (A): Electrolysis of hard water produces O_2 and D_2. Reason (R) :Ordinary hydrogen is called protium.
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 :Both (A) and (R) are correct and (R) is the correct explanation of (A).

Discussion

44.	Assertion (A) Due to Frenkel defect there is no effect on density of a solid. Reason(R)Ions shift from lattice sites to interstitial sites in Frenkel defect.
Answer» Both A and R are TRUE and R is thecorrect explanation of A Both A andR 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

45.	Assertion (A): HF, HCI, CO and No are polar molecules. Reason (R): They have non zero dipole moments and so they are polar molecules.
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

46.	Assertion (A): Depletion of ozone layer causes skin cancer. Reason (R): Depletion of ozone layer will allow more UV rays to reach the earth surface and cause skin cancer.
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 (R). (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

47.	Assertion (A): DDT is banned now-a-days. Reason (R): DDT has a long term toxic effect.
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 OL assertion. Assertion is true but reason is false. Assertion is false but reason is true. Solution :Both (A) and (R) are correct but (R) is not the correct explanation of (A).

Discussion

48.	Assertion (A) CsI is least soluble of all the caesium halides in water.Reasons (A) It is due to low hydration energy.
Answer» SOLUTION :REFER A-level INFORMATION.

Discussion

49.	Assertion (A) : Cs and K are used as electrode in photoelectrical cell. Reason (R) : Cs and K formed superoxide.
Answer» Assertion (A) is true, REASON (R) is true. Reason (R) is a correct EXPLANATION for Assertion (A). Assertion (A) is true, Reason (R) is true, Reason - (R) is not a correct explanation for Assertion (A). Assertion (A) is true, Reason (R) is FALSE Assertion (A) is false, Reason (R) is true. Answer :B

Discussion

50.	Assertion (A) Crystalline solids are anisotropic. Reason(R)The constituent particles are very closely packed.
Answer» Both A and R are true and R is thecorrect EXPLANATION of A Both A ANDR 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

Explore topic-wise InterviewSolutions in Current Affairs.

Assertion (A): If aluminium atom s replace a few silicon atoms in three dimensional network of silicon dioxide, the overall structure acquriesa negative charge. Reason(R): Aluminium is trivalent while silicon is tetravalent.

Assertion (A): Hydrogen reacts faster with halogens than deuterium. Reason (R) : The activation energy of hydrogen is less than that of deuterium.

Assertion (A): Hydrogen peroxide is used in water treatment to oxidise pollutants. Reason (R): The oxidising ability and harmless nature of H_(2)O_(2), is mainly used in many applications,

Assertion (A) Hydrogen peroxide forms only one series of salts called peroxides. Reason (R ) Hydrogen peroxide molecule has only one replaceable hydrogen atom.

Assertion (A): Hydrogen is placed in group-I along with alkali metals. Reason (R): In most of the compounds of hydrogen, exists in the oxidation state.

Assertion (A) :HNO_3 is not a Bronsted acid in CHCl_3 Reason ( R ) :CHCl_3 is an example of aprotic solvent .

Assertion (A): H_(2), Li_(2), C_(2), N_(2) are diamagnetic. Reason (R): All have no unpaired electrons and so they are diamagnetic.

Assertion (A): hep is repersented as abababab ………….. Reason ® : the atoms in thetwo 'a' layers occupy the sites fo the unit cell of hexagonal bravis lattice , the atoms with in the cell ( the b layer) donot occupy sites .

Assertion (A): Heat of neutralization of HClO_(4) with NaOH is same as that of HCl with NaOH Reason (R ): Both HCL and HClO_(4) are strong acids

(A): HCl is not acidic in benzene. (R): Benzene does not accept protons

Assertion (A): Haloarenes do not undergo nucleophilic substitution reactions readily. Reason (R): The C - X bond in aryl halides is short and stronger and also the aromatic ringis a centre of high electron density.

Assertion (A): Haloarenes are insoluble in water. Reason (R): Haloarenes are able to form hydrogen bonds with water.

Assertion (A): Haloalkanes have higher boiling point and melting point than the parent alkanes having the same number of carbon. Reason (R): The intermolecular forces of atraction and dipole-dipole interactions arestronger in haloalkanes.

Assertion (A) : H_(3)BO_(3) is a tribasic weak acid. Reason (R) : B is a typical non-metal.

Assertion (A): Smooth muscles do not show straitions. Reason (R): They are voluntary muscles.

Assertion (A): H_2 and O_2 have same R.M.S. velocity at the same temperature. Reason ® : R.M.S. velocity of a gas molecules is directly proportional to square root its 'T'.

Assertion (A): Greenhouse effect was observed in houses used to grow plants and these are made of green glass Reason (R) : Green house name has been given because glass houses are made of green glass

Assertion (A): Green house effect was observed in houses used to grow plants and these are made of green glass.Reason (R) : Green house name has been given because glass houses are made of green glass.

Assertion (A) : Gases do not liquefy above their critical temperature even on applying high pressure. Reason (R ) : Above critical temperature, the molecular speed is high and intermolecular attractions cannot hold the molecules together because they escape because of high speed.

Assertion (A) : Gases do not liquefy above their critical temperature, even on applying high pressure.Reason (R ) : Above critical temperature, the molecular speed is high and intermolecular attractions cannot hold the molecules together because they escape because of high speed.

Assertion : A free radical is paramagnetic species. Reason : A free radical is formed in homolytic fission of covalent bond.

Assertion (A) : For any chemical reaction at a particular temperature, the equilibrium constant is fixed and is a characteristicproperty. Reason (R) :Equilibrium constant is independent of temperature.

Assertion (A) Following reaction proceed better with KF than with NaF. Reasons (A)-C-Cl+MF rarr-F+MClReason (A) K is more reactive than Na.

Assertion (A) : Fluorescein is an adsorption indicator. Reason (R): Fluorescein is a dye.

Assertion (A) : Finely divided iron acts as a catalyst in Haber's process of manufacture of ammonia from nitrogen and hydrogen. Reason (R):Chemisorption of the reacting nitrogen and hydrogen gases on the surface of iron takes place.

Assertion (A) : First ionization enthalpy of nitrogen is lower than that of oxygen. Reason (R) : Across a period effective nuclear charge decreases Correct answer is,

Assertion (A) : F atom has less negative electron gain enthalpy than Cl atom. Reason (R) : Additional electrons are repelled more effectively by 3p-electrons in Cl atom than by 2p-electrons in F atom.

Assertion (A) : Excessive use of chlorinated synthetic pesticides causes soil and water pollution. Reason (R) : Such pesticides are nonbiodegradable

Assertion (A): Excessive use of chlorinated synthetic pesticides causes soil and water pollution Reason (R) : Such pesticides are non-biodegradable

Assertion (A): Excessive use of chlorinated pesticide causes soil and water pollution. Reason (R): Such pesticides are non-biodegradable. '

Assertion (A): Excessive use of chlorinated pesticide causes soil and water pollution. Reason (R): Such pesticides are non-biodegradable

Assertion (A) : Equilibrium constant of a reaction increases if temperature is increased Reason (R) : The forward reaction becomes faster with increase of temperature.

Assertion (A) : Energy of resonance hybrid is equal to the average of energies of all canonical forms. Reason (R) : Resonance hybrid cannot be represented by a single structure.

Assertion (A): Energy of resonance hybrid is equal to the average of energies of all canonical forms. Reason (R ): Resonance hybrid cannot be presented by a single structure.

Assertion (A) : Energy of resonance hybrid is equal to the average of energies of all canonial forms. Reason (R) : Resonance hybrid cannot be presented by a single structure.

Assertion (A) : Energy of an electron is taken negative. Reason (R ) : Energy of electron at infinity is zero.

Assertion: (A): Emprirical formula of ethane is CH_(3) Reason (R): Empirical formula of all alkenes is CH_(2) The correct answer is

Assertion (A): Electrophilic addition addition of Br_(2) to alkyne proceeds faster tha hta of alkene. Reason (R): Bromonium ion intermediate of alkene is stable that that of alkyne.

Assertion (A) :Electrongain enthapy becomes lessnegativeas we godowna group. Reason ( R) :Size of theatom increases on goindown in thegroup in the addedelectronwould befarther from thenucleus.

Assertion (A): Electron gain enthalpy becomes less negative as we go down a group. Reason (R) : Size of the atom increases on going down the group and the added electron would be farther from the nucleus.

Assertion (A): Electrolysis of hard water produces O_2 and D_2. Reason (R) :Ordinary hydrogen is called protium.

Assertion (A) Due to Frenkel defect there is no effect on density of a solid. Reason(R)Ions shift from lattice sites to interstitial sites in Frenkel defect.

Assertion (A): HF, HCI, CO and No are polar molecules. Reason (R): They have non zero dipole moments and so they are polar molecules.

Assertion (A): Depletion of ozone layer causes skin cancer. Reason (R): Depletion of ozone layer will allow more UV rays to reach the earth surface and cause skin cancer.

Assertion (A): DDT is banned now-a-days. Reason (R): DDT has a long term toxic effect.

Assertion (A) CsI is least soluble of all the caesium halides in water.Reasons (A) It is due to low hydration energy.

Assertion (A) : Cs and K are used as electrode in photoelectrical cell. Reason (R) : Cs and K formed superoxide.

Assertion (A) Crystalline solids are anisotropic. Reason(R)The constituent particles are very closely packed.