Practice Questions

Q33.The potassium ferrocyanide solution gives a Prussian blue colour, when added to : (1) CoCl3 (2) CoCl2 (3) FeCl2 (4) FeCl3

Q33.In the following the correct bond order sequence is: (1) O2−2 > O+2 > O−2 > O2 (2) O+2 > O−2 > O2−2 > O2 (3) O+2 > O2 > O−2 > O2−2 (4) O2 > O−2 > O2−2 > O+2

Q33.Deuterium resembles hydrogen in properties but: JEE Main 2021 (27 Aug Shift 1) JEE Main Previous Year Paper (1) reacts vigorously than hydrogen (2) reacts just as hydrogen (3) emits β+ particles (4) reacts slower than hydrogen

Q33.Which one of the following statements is incorrect ? (1) Atomic hydrogen is produced when H2 (2) At around 2000 K, the dissociation of molecules at a high temperature are irradiated dihydrogen into its atoms is nearly 8 . 1% with UV radiation. (3) Bond dissociation enthalpy of H2 is highest (4) Dihydrogen is produced on reacting zinc with among diatomic gaseous molecules which HCl as well as NaOH . ( aq ) . contain a single bond.

Q33.The number of neutrons and electrons, respectively, present in the radioactive isotope of hydrogen is :- (1) 1 and 1 (2) 3 and 1 (3) 2 and 1 (4) 2 and 2

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.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.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.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.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.The major component/ingredient of Portland Cement is : (1) dicalcium silicate (2) tricalcium aluminate (3) dicalcium aluminate (4) tricalcium silicate

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.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.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.Al2O3 was leached with alkali to get X . The solution of X on passing of gas Y, forms Z . X, Y and Z respectively are (1) X = AlOH3, Y = CO2', Z = Al2O3 (2) 𝑋= NaAlOH4, Y = SO2, Z = Al2O3 (3) X = AlOH3, Y = SO2, Z = Al2O3 · xH2O (4) 𝑋= NaAlOH4, Y = CO2, Z = Al2O3, 𝑥H2O

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.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.The oxidation states of ′P′ in H4P2O7, H4P2O5 and H4P2O6, respectively, are : (1) 7, 5 and 6 (2) 5, 4 and 3 (3) 5, 3 and 4 (4) 6, 4 and 5

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

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.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.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.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 INCORRECT statement(s) about heavy water is (are) (A) used as a moderator in nuclear reactor (B) obtained as a by-product in fertilizer industry. (C) used for the study of reaction mechanism (D) has a higher dielectric constant than water Choose the correct answer from the options given below: (1) (B) only (2) (C) only (3) (D) only (4) (B) and (D) only

Q34.Which of the following compound is added to the sodium extract before addition of silver nitrate for testing of halogens? (1) Nitric acid (2) Sodium hydroxide (3) Ammonia (4) Hydrochloric acid