52671 + Interview Questions in Chemistry in Class 11

1.	Assertion . Sodium reacts with oxygen to form Na_(2)O_(2) but potassium reacts with oxygen to form KO_(2) Reason. Potassium is more reactive than sodium .
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 . Due to bigger size of `K^(+)` than `NA^(+)`, it has a WEAK positive field around it which cannot prevent peroxide ion `(O_(2)^(2-))` to combine with another OXYGEN ATOM to form superoxide , `O_(2)^(-)` .

Discussion

2.	Assertion. SnI_(4) is an orange solid. Reason. The colour arisesdue to charge transfer.
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 not is the true explanation of the assertion. If assertion is true, but reason is false. If both assertion and reason are false. Answer :A

Discussion

3.	Assertion: Sky appears blue in colour. Reason: Colloidal particles od dust scatter blue light.
Answer» if both ASSERTION and reason are TRUE and the reason is the correct EXPLANATION of the assertion. If both assertion and reason 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 :The sky appears blue because the colloidal particles of DUST, dirt in air scatter blue light to the MAXIMUM extent. Here both assertion and reason are correct and reason is the correct explanation of assertion.

Discussion

4.	Assertion. Size of the cation is larger in tetrahedral hole than in an octahedral hole. Reason. The cations occupy more space than anions in crystal packing.
Answer» Solution :CORRECT A. Octahedral hole is LARGE in size than tetrahedral hole. Correct R. cations are generally smaller. They OCCUPY the voids and HECE occupy LESS space.

Discussion

5.	Assertion :Silver can displace copper from CuSO_4 solution. Reason :Silver is placed below copper in the electrochemical series.
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 :D

Discussion

6.	Assertion. Siliconsare hydrophobic in nature. Reason. Si-O-Silinkage are moisture sensitive.
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 not is the true explanation of the assertion. If assertion is true, but reason is false. If both assertion and reason are false. Solution :CORRECT reason. Si ATOMS in silicones are SURROUNDED by non-polar alkyl GROUPS, which repel WATER molecules.

Discussion

7.	Assertion. SiF_(6)^(2-)is known but SiCl_(6)^(2-)is not. Reason. Size of F is smalland its lone pair ofelectrons intract with d-orbitalsof Si strongly.
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 not is the true explanation of the assertion. If assertion is true, but reason is false. If both assertion and reason are false. Answer :A

Discussion

8.	Assertion SF_(6) is not a stable molecule. Reason . A stable molecule must have 8 electrons around the central atom, i.e., octet rule should be satisfied.
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 both assertion and reason are incorrect. Solution :Correct A. `SF_(6)` is a stable MOLECULE . Correct R . Some molecules are electrons deficinet or have expended OCTET, yet they are stable .

Discussion

9.	Assertion: Semiconductors are solids with conductivities in the intermediate range from 10^(-6) -10^4 "ohm"^(-1) m^(-1) Reason : Intermediate conductivityin semiconductor is due to partially filled valence band .
Answer» Assertion and reason both are correct statements and reason is correct explanation for assertion. 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 is wrong statement but reason is correct statement. SOLUTION :Correct Reason. INTERMEDIATE CONDUCTIVITY of semiconductors is due to small ENERGY gap between FILLED valence band and empty conduction band.

Discussion

10.	Assertion . SeCl_(4)does not have a tetrahedral structure . Resason . Se in SeCl_(4) has two lone pairs .
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 both assertion and reason are incorrect. Solution :`SeCl_(4)` has distorted trigonal bipyramidal structrue Hence, assertion is ture . Correct R . Se in `SeCl_(4)` has one LONE pair Se has the outer shell electronic configuration ` 4s^(2) 4p_(x)^(2) 4p_(y)^(1) 4p_(z)^(1) ` or in theexcited state it is` 4s^(2) 4p_(x)^(1) p_(x)^(1) 4p_(y)^(1) 4p_(z)^(1) 4d^(1)`. itundergoes `SP^(3) d ` HYBRIDIZATION . In the trigonal bipyramidal structure, one position of the triangular base is occupied by one lone pair . The distortion in shape is due to the presence of this lone pair .

Discussion

11.	Assertion: Scientific notation forthe number 100 is expressed as 1xx10^2 Reason : The number 1xx10^2 has two significant figures.
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 correct explanation of assertion. If assertion is true but reason is false. If both assertion and reason are false. Solution :The TERMINAL zeros are not significant if there is no decimal point. Hence, the number `1xx10^2` has only one significant figure.

Discussion

12.	Assertion. Sb (III) is not precipitated as sulphide when in its alkaline solution, H_(2)S is passed. Reason. The concentration of S^(2-) ion in alkaline medium is inadequate for precipitation.
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 aasertion is true, but reason is false. If both assertion and reason are false. Solution :Correct A. The pH at the END point of only a strong ACID with strong base is 7. Correct R. SB (III) is precipitated (in Group IIB) by `H_(2)S` in acidic medium (dil . HCl) . In acidic medium, `S^(2-)` concentration decreases so that radicals of Group IV are not precipitated. In alkaline medium, `S^(2-)` ion concentration increases and not decreases.

Discussion

13.	Assertion : Saline hydrides react violently with water producing dihydrogen gas. Reason: The metals of group 6, 7, 8 and 9 do not from hydride.
Answer» Both Assertion (A) and REASON (R) are true and Reason (R) is the correct explanation of Assertion (A) Both (A) and (R) are true but (R) is not the correct explanation of (A) (A) is true but (R) is FALSE (A) and (R) both are false. Answer :C

Discussion

14.	Assertion: Rotation about C=C is restricted. Reason: Electron charge cloud of the pi bond is located aboe na dbelow the planne of bonding atoms.
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 :In a `pi` bond FORMATION, parallel orientation of the two p orbitals on adjacent atoms is necessary for proper sideways overlap. The p orbitals are mutually parallel and both the p orbitals are perpendicular to the plane of the molecule. Rotation of ONE `CH_(2)` fragment with respect to other, interferes with MAXIMUM overlap of p orbitals and hence such rotation is RESTRICTED.

Discussion

15.	Assertion: Roasting ore with NaCl is called chloridising roasting. Reason: Chlorides are easily soluble in water.
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 :Roasting ORE with NaCl is CALLED chloridising because chlorides are produced in the process (eg. AGCL)

Discussion

16.	Assertion: Removal of s electrons is relatively difficult than removal of p-electron of same main shell. Reason: s electrons are closer to the nucleus than p electrons of the same shell and hence are more strongly attracted by the nucleus.
Answer» Both A and B true and R is the CORRECT explanation 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

17.	Assertion: Reducing sugars undergo mutarotion. Reason: during mutarotaiton, one anomeric form is converted into an equilibrium mixture of two anomers.
Answer» Both A and R are TRUE and R is the correct EXPLANATION of A both A and R 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

18.	Assertion: Recent convention to represent K_(p) is dimensionless. Reason: The statement state of pure gas is 1 bar and the partial pressure of reactants and products measured with respect to this standerd are determine K_(p) for the equilibrium. A(g) + 2B(g) rarr C(g)
Answer» If both assertion and REASON are true and the reason is the correct explanation of the assertion. If both assertion and reason are true but reason is not the correct explanation of the assertion. If assertion is true but reason is false. If assertion is false but reason is true. Solution :LET partial pressure of reactants and products are a,b,c BAR respectively with respect to STANDARD state, then For `A(g) + 2B(g)` `rarr` `C(g)` `P'_(A) = (alpha bar)/(1 bar) = 1` Similarly, `P'_(B) = b` and `P'_(c) =0` Thus, `K_(p) = (c)/(axxb^(2))` is dimensionless.

Discussion

19.	Assertion : (RCO_(2)O), RCOCl and RCOOR' all react with RMgX to give 3^(@) alcohols Reason : RCOCl reacts with R_(2)Cd to form ketones but (RCO)_(2)O and RCOOR' do not react at all
Answer» Both A and R are true 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

20.	Assertion. Rates of nitration of benzene and hexadeuterobenzene are different. Reason. C-H bond is stronger than C-D 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 assertion. Rates of NITRATION of BENZENE and hexadeuterobenzene are same. Correct assertion. The C-D or C-H BOND is not involved in rate-determining step of the REACTION.

Discussion

21.	Assertion: Radius of the ion is always smaller than the parent atom. Reason: Ion is formed by the loss or gain of electrons by the parent atom.
Answer» Both A and B TRUE and R is the CORRECT EXPLANATION 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 :D

Discussion

22.	Assertion. Propene is more reactive than ethene towards electrophilic addition reactions Reason. Hyperconjugation effect of the CH_3 group increases the electron density in the double 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 Answer :A

Discussion

23.	Assertion. Propene reacts with hydrogen chloride in presence of organic peroxide to give 1-chloropropane Reason. Addition of HCl follows Kharasch effect
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 assertion. PROPENE reacts with HCL in presence or absence of BENZOYL peroxide to form 2-chloropropane. Correct reason. Addition of HCl does not follow Kharasch effect.

Discussion

24.	Assertion : Pressure of a dry gas at any temperature can be calculated by substracting aqueous tension at that temperature from the pressure of the moist gas. Reason : The pressure of water vapours is called aqueous tension.
Answer» If both assertion and reason are correct and reason is correct explanation for assertion If both assertion and reason are correct and reason is not correct explanation for assertion If assertion is correct but reason is incorrect If assertion and reason are both incorreect. Solution :Correct explanation : The molecules of the GAS and that of water do not REACT chemically.

Discussion

25.	Assertion. Precipitation of soap is made by the addition of salt (NaCl). Reason. Presence of common ion suppresses the dissociation of weak acid.
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 aasertion is true, but reason is false. If both assertion and reason are false. Solution :CORRECT R. Salting out action of SOAP is based on the principle of solubility product. Common ion effect is for weak ELECTROLYTES (weak acids or weak bases).

Discussion

26.	Assertion .Potassium carbonate cannot be manufactured by a process similar to the Solvay's soda ammonia process . Reason . Potassium hydrogen carbonate is less soluble in water than sodium hydrogen carbonate .
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 reason . `KHCO_(3)` is more soluble in `H_(2)O` than `NaHCO_(3)`.

Discussion

27.	Assertion. Pi bond is never formed alone . It is formed along with a sigma bond . Reason. Pi bond isformed by sideway overlap of p-orbitals only.
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 both assertion and reason are incorrect. Solution :Correct R . PI bond MAY be formed by sideway overlap of p with p or p with d - ORBITALS.

Discussion

28.	Assertion: Photochemical smog is oxidizing in nature.Reason : Photochemical smog contains NO_2 and O_3, which are formed during the sequence of reactions.
Answer» ANSWER :a

Discussion

29.	Assertion. Photochemical smog does not involve the condensation of any kind of fog on smoke particles andhence the word smog is a misnomer Reason. Photochemical smog is due to photochemical oxidation of SO_2 to SO_3 which dissolves in moisture of the air to form sulphurous acid which is injurious to health.
Answer» If both ASSERTION and REASON are TRUE and Reason is the correct explanation of Assertion. Both Assertion and Reason are true but Reasonis not the correct explanation of Assertion If Assertion is true but Reason is false If both Assertion and Reason are false Solution :Correct Reason.Photochemical SMOG is due to reaction of `NO_2` with hydrocarbons present in the AIR

Discussion

30.	Assertion. pH of neutral solution is always 7. Reason. pH of a solution does not depend upon temperature.
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 aasertion is true, but reason is false. If both assertion and reason are false. SOLUTION :Correct A. pH of a neutral solution is 7 only at 298 K. Correct R. pH ofa solution CHANGES with temperature.

Discussion

31.	Assertion : pH of rainy water is around 5.6. Reason : Water reacts with CO_2 in atmosphere and produce H^+.
Answer» Both ASSERTION and Reason are correct and the reason is the correct explanation for assertion. Both assertion and reason are correct, but the reason is not correct explanation of assertion. Both the assertion and reason are incorrect. The assertion is incorrect but the reason is correct. Solution :`H_2 CO_3` (carbonic ACID) is produced by REACTION of `CO_2` with water. Which is decomposed to FORMED `H^+` , due to that water become acidic. Thus its pH VALUE is around 5.6.

Discussion

32.	Assertion : Permanent hardness of water is removed by treatment with washing soda. Reason : Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates
Answer» Both ASSERTION and REASON are TRUE but reason is not the correct explanation of assertion. Both assertion and reason are truebut reason is not the correct explanation of assertion Assertion is true but reason is FALSE Both assertion and reason are false Solution :`Ca^(2+)+Na_(2)CO_(3)toCaCO_(3)darr+2Na^(+)`.

Discussion

33.	Assertion : Permanent hardness of water is removed by treatment with washing soda Reason : Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates
Answer» both assertion and REASON are TRUE and reason is the correct explanation of assertion. Both assertion and reason are true but reasonis not the correct explanation of assertion. Assertion is true but reason is false both assertion and reason are false ANSWER :A::B::C::D

Discussion

34.	Assertion : Permanent hardness of water can be removed by using washing soda. Reason : Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates.
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. ANSWER :A

Discussion

35.	Assertion: PCl_5 is covalent in gaseous and liquid states but ionic in solid state. Reason: PCl_5 in solid state consists of tetrahedral PCl_4^+cation and octahedral PCl_6^-anion.
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 :`PCl_5`is trigonal bipyramidal containing `sp^3d` hybridized P ATOM in LIQUID and gaseous states whereas in solid state it consists of tetrahedral `PCl_4^+` cation and octahedral `PCl_6^-`anion.

Discussion

36.	Assertion. PbCl_(2) is more stable than PbCl_(4). Reason. PbCl_(4) is a powerfuloxidising agent.
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 not is the true explanation of the assertion. If assertion is true, but reason is false. If both assertion and reason are false. Answer :A

Discussion

37.	Assertion. PbI_(4) is a stablethan PbCl_(4). Reason. Iodide ion stabilizeshigher oxidationstate.
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 not is the true explanation of the assertion. If assertion is true, but reason is false. If both assertion and reason are false. Solution :Correct assertion. `PbI_(4)` is UNSTABLE. Correct reason. `I^(-)` being a reducing agent, reduces `Pb^(4+)`to `Pb^(2+)` or `Pb^(4+)` being an OXIDISING agent oxidises `I^(-)` to `I_(2)`.

Discussion

38.	Assertion: Pb^(4+) "ion can easily reduced to" Pb^(2+) ion. Reason: Pb^(2+) ion is paramagnetic in nature
Answer» If both assetion and reson are corect and reason is CORRECT explanation for assertion If both assetion and reason are correct but reason is not correct explanation for assertion If ASERTION is correct but reason is incorrect If both assetion and reason are incorrect Solution :Correct reason,. `PB^(2+)` ion is more STABLE than `Pb^(2+)` ion

Discussion

39.	Assertion: Pb, Sn and Bi are purified by liquation, Reason: Pb, Sn and Bi have lower m.pt then the impurities present .
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 :Both assertioin (A) and reason (R) are true and R is the correct explanation of A

Discussion

40.	Assertion: Paper chromatography is a type of partition chromatography. Reason: Moving phase is liquid and stationary phase is solid.
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 :Chromatography paper CONTAINS water trapped in it, which acts as the stationary phase. Mobile phase is SOLVENT or a mixture off solvents in which spotted chromatography paper is suspended. THUS, both mobile and stationary phase are LIQUIDS.

Discussion

41.	Assertion. P_(4) is more reactive than N_(2). Reason, P-P single bond is much weakern as compared to N-=N triple bond.
Answer» If both ASSERTION and REASON are TRUE, and is the correct EXPLANATION of the assertion. If both assertion and reason are true, but reason is not the correct explanation of the assertion. If assertion is true, but reason is false. If both assertion and reason are false Answer :A

Discussion

42.	Assertion: Ozone is destroyed by solar radiation in upper atmosphere.Reason: Thinning of the ozone layer allows excessive UV radiations to reach the surface of earth.
Answer» ANSWER :d

Discussion

43.	Assertion: Oxygen molecule is paramagnetic. Reason: It has two unpaired electron in its bonding molecular orbital
Answer» Both assertion and reason are TRUE and reason is not the correct EXPLANATION ofassertion both assertion and reason are true but reason is not the correct explanation of assertion assertion is but reason is false Both assertion and reason are false ANSWER :A::B::C

Discussion

44.	Assertion : Oxygen molecule is paramagnetic . Reason : It has two unpaired electron in its bonding molecular orbital.
Answer» both ASSERTION and reason are true and reason is the CORRECT EXPLANATION of assertion both assertion and reason are true but reason is not the correct explanation of assertion assertion is true but reason is false Both assertion and reason are false Answer :C

Discussion

45.	Assertion : Oxidation state of hydrogen in H_2O is +1 . Reason : CaH_2 is metal hydride and for hydrides hydrogen is assigned the oxidation state of - 1.
Answer» Assertion and REASON both are CORRECT statements and reason is correct explanation for assertion. 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 is wrong statement but reason is correct statement. ANSWER :a

Discussion

46.	Assertion : Oxidation state of carbon in its compounds is +4 Reason : An element has a fixed oxidation state.
Answer» If both assetion and RESON are corect and reason is correct explanation for assertion If both assetion and reason are correct but reason is not correct explanation for assertion If asertion is correct but reason is INCORRECT If both assetion and reason are incorrect Solution :Correct Assetion : The oxidation state of CARBON in compounds depends upopn the nature of the compounds Correct Reason : An ELEMENT may not have a fixed oxidation state.

Discussion

47.	Assertion. Oxidation of toluene as well as ethylbenzene with KMnO_4 gives benzoic acid. Reason. Both toluene and ethylbenzene are more reactive than benzene towards electrophilic substitution reaction.
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. Irrespective of the LENGTH of the side chain, oxidation OCCURS at the more reactive benzylic CARBON leading to the formation of benzoic acid.

Discussion

48.	Assertion :Oxidation number of C in HCHO is zero. Reason : Formaldehyde is a covalent compound.
Answer» Assertion and REASON both are CORRECT statements and reason is correct explanation for assertion. 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 is wrong statement but reason is correct statement. Answer :B

Discussion

49.	Assertion :Oxidation and reduction are complementary to each otherReason:A substance will lose electrons only when some other substance will gain them . Thus. A substance gets oxidised only when some other substance gets reduced.
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 :A

Discussion

50.	Assertion : Oxidation number of phosphorus in P_4 is zero. Reason : Phosphorus has oxidation state zero in all its compound .
Answer» Assertion and REASON both are CORRECT STATEMENTS and reason is correct EXPLANATION for assertion. 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 is wrong statement but reason is correct statement. Answer :C

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Assertion . Sodium reacts with oxygen to form Na_(2)O_(2) but potassium reacts with oxygen to form KO_(2) Reason. Potassium is more reactive than sodium .

Assertion. SnI_(4) is an orange solid. Reason. The colour arisesdue to charge transfer.

Assertion: Sky appears blue in colour. Reason: Colloidal particles od dust scatter blue light.

Assertion. Size of the cation is larger in tetrahedral hole than in an octahedral hole. Reason. The cations occupy more space than anions in crystal packing.

Assertion :Silver can displace copper from CuSO_4 solution. Reason :Silver is placed below copper in the electrochemical series.

Assertion. Siliconsare hydrophobic in nature. Reason. Si-O-Silinkage are moisture sensitive.

Assertion. SiF_(6)^(2-)is known but SiCl_(6)^(2-)is not. Reason. Size of F is smalland its lone pair ofelectrons intract with d-orbitalsof Si strongly.

Assertion SF_(6) is not a stable molecule. Reason . A stable molecule must have 8 electrons around the central atom, i.e., octet rule should be satisfied.

Assertion: Semiconductors are solids with conductivities in the intermediate range from 10^(-6) -10^4 "ohm"^(-1) m^(-1) Reason : Intermediate conductivityin semiconductor is due to partially filled valence band .

Assertion . SeCl_(4)does not have a tetrahedral structure . Resason . Se in SeCl_(4) has two lone pairs .

Assertion: Scientific notation forthe number 100 is expressed as 1xx10^2 Reason : The number 1xx10^2 has two significant figures.

Assertion. Sb (III) is not precipitated as sulphide when in its alkaline solution, H_(2)S is passed. Reason. The concentration of S^(2-) ion in alkaline medium is inadequate for precipitation.

Assertion : Saline hydrides react violently with water producing dihydrogen gas. Reason: The metals of group 6, 7, 8 and 9 do not from hydride.

Assertion: Rotation about C=C is restricted. Reason: Electron charge cloud of the pi bond is located aboe na dbelow the planne of bonding atoms.

Assertion: Roasting ore with NaCl is called chloridising roasting. Reason: Chlorides are easily soluble in water.

Assertion: Removal of s electrons is relatively difficult than removal of p-electron of same main shell. Reason: s electrons are closer to the nucleus than p electrons of the same shell and hence are more strongly attracted by the nucleus.

Assertion: Reducing sugars undergo mutarotion. Reason: during mutarotaiton, one anomeric form is converted into an equilibrium mixture of two anomers.

Assertion: Recent convention to represent K_(p) is dimensionless. Reason: The statement state of pure gas is 1 bar and the partial pressure of reactants and products measured with respect to this standerd are determine K_(p) for the equilibrium. A(g) + 2B(g) rarr C(g)

Assertion : (RCO_(2)O), RCOCl and RCOOR' all react with RMgX to give 3^(@) alcohols Reason : RCOCl reacts with R_(2)Cd to form ketones but (RCO)_(2)O and RCOOR' do not react at all

Assertion. Rates of nitration of benzene and hexadeuterobenzene are different. Reason. C-H bond is stronger than C-D bond.

Assertion: Radius of the ion is always smaller than the parent atom. Reason: Ion is formed by the loss or gain of electrons by the parent atom.

Assertion. Propene is more reactive than ethene towards electrophilic addition reactions Reason. Hyperconjugation effect of the CH_3 group increases the electron density in the double bond

Assertion. Propene reacts with hydrogen chloride in presence of organic peroxide to give 1-chloropropane Reason. Addition of HCl follows Kharasch effect

Assertion : Pressure of a dry gas at any temperature can be calculated by substracting aqueous tension at that temperature from the pressure of the moist gas. Reason : The pressure of water vapours is called aqueous tension.

Assertion. Precipitation of soap is made by the addition of salt (NaCl). Reason. Presence of common ion suppresses the dissociation of weak acid.

Assertion .Potassium carbonate cannot be manufactured by a process similar to the Solvay's soda ammonia process . Reason . Potassium hydrogen carbonate is less soluble in water than sodium hydrogen carbonate .

Assertion. Pi bond is never formed alone . It is formed along with a sigma bond . Reason. Pi bond isformed by sideway overlap of p-orbitals only.

Assertion: Photochemical smog is oxidizing in nature.Reason : Photochemical smog contains NO_2 and O_3, which are formed during the sequence of reactions.

Assertion. pH of neutral solution is always 7. Reason. pH of a solution does not depend upon temperature.

Assertion : pH of rainy water is around 5.6. Reason : Water reacts with CO_2 in atmosphere and produce H^+.

Assertion : Permanent hardness of water is removed by treatment with washing soda. Reason : Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates

Assertion : Permanent hardness of water is removed by treatment with washing soda Reason : Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates

Assertion : Permanent hardness of water can be removed by using washing soda. Reason : Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in hard water to form insoluble carbonates.

Assertion: PCl_5 is covalent in gaseous and liquid states but ionic in solid state. Reason: PCl_5 in solid state consists of tetrahedral PCl_4^+cation and octahedral PCl_6^-anion.

Assertion. PbCl_(2) is more stable than PbCl_(4). Reason. PbCl_(4) is a powerfuloxidising agent.

Assertion. PbI_(4) is a stablethan PbCl_(4). Reason. Iodide ion stabilizeshigher oxidationstate.

Assertion: Pb^(4+) "ion can easily reduced to" Pb^(2+) ion. Reason: Pb^(2+) ion is paramagnetic in nature

Assertion: Pb, Sn and Bi are purified by liquation, Reason: Pb, Sn and Bi have lower m.pt then the impurities present .

Assertion: Paper chromatography is a type of partition chromatography. Reason: Moving phase is liquid and stationary phase is solid.

Assertion. P_(4) is more reactive than N_(2). Reason, P-P single bond is much weakern as compared to N-=N triple bond.

Assertion: Ozone is destroyed by solar radiation in upper atmosphere.Reason: Thinning of the ozone layer allows excessive UV radiations to reach the surface of earth.

Assertion: Oxygen molecule is paramagnetic. Reason: It has two unpaired electron in its bonding molecular orbital

Assertion : Oxygen molecule is paramagnetic . Reason : It has two unpaired electron in its bonding molecular orbital.

Assertion : Oxidation state of hydrogen in H_2O is +1 . Reason : CaH_2 is metal hydride and for hydrides hydrogen is assigned the oxidation state of - 1.

Assertion : Oxidation state of carbon in its compounds is +4 Reason : An element has a fixed oxidation state.

Assertion. Oxidation of toluene as well as ethylbenzene with KMnO_4 gives benzoic acid. Reason. Both toluene and ethylbenzene are more reactive than benzene towards electrophilic substitution reaction.

Assertion :Oxidation number of C in HCHO is zero. Reason : Formaldehyde is a covalent compound.

Assertion :Oxidation and reduction are complementary to each otherReason:A substance will lose electrons only when some other substance will gain them . Thus. A substance gets oxidised only when some other substance gets reduced.

Assertion : Oxidation number of phosphorus in P_4 is zero. Reason : Phosphorus has oxidation state zero in all its compound .