Practice Questions

Q34.The solubility of AgCN in a buffer solution of pH = 3 is x . The value of x is: [Assume : No cyano complex is formed ; Ksp(AgCN) = 2. 2 × 10−16 and Ka(HCN) = 6. 2 × 10−10 ] (1) 1. 9 × 10−5 (2) 2. 2 × 10−16 (3) 0. 625 × 10−6 (4) 1. 6 × 10−6

Q34.Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Hydrogen is the most abundant element in the Universe, but it is not the most abundant gas in the troposphere. Reason R: Hydrogen is the lightest element. In the light of the above statements, choose the correct answer from the options given below: (1) Both A and R are true but R is NOT the correct (2) Both A and R are true and R is the correct explanation of A explanation of A (3) A is true but R is false (4) A is false but R true JEE Main 2021 (24 Feb Shift 2) JEE Main Previous Year Paper

Q34.Given below are the statements about diborane (a) Diborane is prepared by the oxidation of NaBH4 with I2 (b) Each boron atom is in sp2 hybridized state (c) Diborane has one bridged 3 centre- 2 -electron bond (d) Diborane is a planar molecule The option with correct statement(s) is (1) (c) and (d) only (2) (a) only (3) (c) only (4) (a) and (b) only

Q34.Choose the correct statement from the following : (1) LiF has least negative standard enthalpy of (2) The standard enthalpy of formation for alkali formation among alkali metal fluorides. metal bromides becomes less negative on descending the group. (3) The low solubility of CsI in water is due to its (4) Among the alkali metal halides, LiF is least high lattice enthalpy. soluble in water.

Q34.Match List −I with List −II List −I List −II (a) Ca(OCl)2 (i) Antacid (b) CaSO4 ⋅12 H2O (ii) Cement (c) CaO (iii) Bleach (d) CaCO3 (iv) Plaster of paris Choose the most appropriate answer from the (1) a −i, b −iv, c −iii, d −ii (2) a −iii, b −ii, c −iv, d −i (3) a −iii, b −iv, c −ii, d −i (4) a −iii, b −ii, c −i, d −iv

Q34.Identify the species having one π -bond and maximum number of canonical forms from the following : (1) SO3 (2) O2 (3) SO2 (4) CO2−3

Q34.The exact volumes of 1 M NaOH solution required to neutralise 50 mL of 1 M H3 PO3 solution and 100 mL of 2 M H3 PO2 solution, respectively, are : (1) 100 mLand 100 mL (2) 100 mL and 50 mL (3) 100 mL and 200 mL (4) 50 mL and 50 mL

Q34.Which one of the following compounds of Group-14 elements is not known? (1) GeCl6 2 - (2) SnOH6 2 - (3) SiCl6 2 - (4) SiF6 2 -

Q34.Given below are two statements: Statement I : Both CaCl2. 6H2O and MgCl2. 8H2O undergo dehydration on heating. Statement II : BeO is amphoteric, whereas the oxides of other elements in the same group are acidic. In the light of the above statements, choose the correct answer from the options given below: (1) Statement I is false but statement II is true (2) Both statement I and statement II are false (3) Both statement I and statement II are true (4) Statement I is true but statement II is false

Q34.Match List- I with List- II. List- I List- II (Molecule) (Bond order) (a) Ne2 (i) 1 (b) N2 (ii) 2 (c) F2 (iii) 0 (d) O2 (iv) 3 Choose the correct answer from the options given below: (1) (a) →(ii), (b) →(i), (c) →(iv), (d) →(iii) (2) (a) →(iii), (b) →(iv), (c) →(i), (d) →(ii) (3) (a) →(i), (b) →(ii), (c) →(iii), (d) →(iv) (4) (a) →(iv), (b) →(iii), (c) →(ii), (d) →(i)

Q34.A solution is 0. 1M in Cl− and 0. 001M in CrO2−4 . Solid AgNO3 is gradually added to it Assuming that the addition does not change in volume and Ksp(AgCl) = 1. 7 × 10−10M2 and Ksp(Ag2 CrO4) = 1. 9 × 10−12M3. Select correct statement from the following: (1) AgCl precipitates first because its Ksp is high. (2) Ag2 CrO4 precipitates first as its Ksp is low. (3) Ag2 CrO4 precipitates first because the amount of Ag+ needed is low. (4) AgCl will precipitate first as the amount of Ag+ needed to precipitate is low.

Q34.The number of water molecules in gypsum, dead burnt plaster and plaster of Paris, respectively are: (1) 2, 0 and 0. 5 (2) 0. 5, 0 and 2 (3) 2, 0 and 1 (4) 5, 0 and 0. 5

Q34.Given below are two statements : One is labelled as Assertion A and other is labelled as Reason R. Assertion A : The dihedral angles in H2O2 in gaseous phase is 90. 2° and in solid phase is 111. 5° . Reason R : The change in dihedral angle in solid and gaseous phase is due to the difference in the intermolecular forces. Choose the most appropriate answer from the options given below for A and R. (1) A is correct but R is not correct. (2) Both A and R are correct but R is not the correct explanation of A. (3) Both A and R are correct and R is the correct (4) A is not correct but R is correct. explanation of A .

Q34.Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Dipole-dipole interactions are the only non-covalent interactions, resulting in hydrogen bond formation. Reason R : Fluorine is the most electronegative element and hydrogen bonds in HF are symmetrical. In the light of the above statements, choose the most appropriate answer from the options given below: (1) A is false but R is true (2) Both A and R are true but R is NOT the correct explanation of A (3) A is true but R is false (4) Both A and R are true and R is the correct explanation of A

Q34.What are the products formed in sequence when excess of CO2 is passed in slaked lime? (1) CaO, CaCO3 (2) Ca (HCO3)2′ CaCO3 (3) CaCO3, Ca (HCO3)2 (4) CaO, Ca (HCO3)2

Q34.Match List - I with List II : List-I List-II a Li i photoelectric cell b Na ii absorbent of CO2 c K iii coolant in fast breeder nuclear reactor d Cs iv treatment of cancer v bearings for motor engines Choose the correct answer from the options given below: (1) (a ) -( v ),( b )-( i ),( c )-( ii ),( d )-( iv) (2) (a ) -( v ),( b )-( ii ),( c )-( iv ),( d )-( i) (3) (a ) - ( iv ), ( b ) - ( iii ), ( c ) - ( i ), ( d ) - ( ii) (4) (a ) - ( v ), ( b ) - ( iii ), ( c ) - ( ii ), ( d ) - ( i)

Q34.In basic medium, H2O2 exhibits which of the following reactions? (A) Mn2+ →Mn4+ (B) I2 →I− (C) PbS →PbSO4 Choose the most appropriate answer from the options given below : (1) (A),(C) only (2) (A) only (3) (B) only (4) (A), (B) only

Q34.Which one of the following compounds is aromatic in nature? (1) (2) (3) Both A and B (4)

Q34.The set of elements that differ in mutual relationship from those of the other sets is: (1) Li −Mg (2) B −Si (3) Be −Al (4) Li −Na

Q34.Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Heavy water is used for the study of reaction mechanism. Reason (R): The rate of reaction for the cleavage of O −H bond is slower than that of O −D bond. Choose the most appropriate answer from the options given below : (1) Both (A) and (R) are true and (R) is the true (2) (A) is true but (R) is false. explanation of (A) . (3) (A) is false but (R) is true. (4) Both (A) and (R) are true but (R) is not the true explanation of (A).

Q35.Given below are two statements : Statement I : Aniline is less basic than acetamide. Statement II : In aniline, the lone pair of electrons on nitrogen atom is delocalised over benzene ring due to resonance and hence less available to a proton. Choose the most appropriate option ; (1) Statement I is true but statement II is false. (2) Statement I is false but statement II is true. (3) Both statement I and statement II are true. (4) Both statement I and statement II are false.

Q35.Which of the following equation depicts the oxidizing nature of H2O2 ? (1) 2I−+ H2O2 + 2H+ →I2 + 2H2O (2) I2 + H2O2 + 2 OH−→2I−+ 2H2O + O2 (3) Cl2 + H2O2 →2HCl + O2 (4) KIO4 + H2O2 →KIO3 + H2O + O2

Q35.Match List - I with List - II : List - I (Metal ion) List - II (Group in Qualitative analysis) (a) Mn2 + (i) Group - III (b) As3 + (ii) Group - IIA (c) Cu2 + (iii) Group - IV (d) Al3 + (iv) Group - IIB Choose the most appropriate answer from the options given below : (1) (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i) (2) (a)-(iv), (b)-(ii), (c)-(iii), (d)-(i) (3) (a)-(i), (b)-(iv), (c)-(ii), (d)-(iii) (4) (a)-(i), (b)-(ii), (c)-(iii), (d)-(iv) JEE Main 2021 (31 Aug Shift 2) JEE Main Previous Year Paper

Q35.Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Assertion (A): A simple distillation can be used to separate a mixture of propanol and propanone. Reason (R): Two liquids with a difference of more than 20°C in their boiling points can be separated by simple distillations. In the light of the above statements, choose the most appropriate answer from the options given below : (1) Both (A) and (R) are correct but (R) is not the (2) Both (A) and (R) are correct and (R) is the correct explanation of (A). correct explanation of (A). (3) (A) is true but (R) is false. (4) (A) is false but (R) is true.

Q35.The correct order of conductivity of ions in water is: (1) Na+ > K+ > Rb+ > Cs+ (2) Cs+ > Rb+ > K+ > Na+ (3) K+ > Na+ > Cs+ > Rb+ (4) Rb+ > Na+ > K+ > Li+