Practice Questions

Q36.In order to oxidize a mixture of one mole of each of FeC2O4, Fe2 ( C2O4 ) 3, FeSO4 and Fe2 ( SO4 ) 3 in acidic medium, the number of moles of KMnO4 is: (1) 1 (2) 2 (3) 3 (4) 1.5

Q37.What is the molar solubility of AIOH3 in 0.2 M NaOH solution? Given that, solubility product of AlOH3 = 2.4 × 10-24 : (1) 3 × 10-19 (2) 12 × 10-21 (3) 12 × 10-23 (4) 3 × 10-22

Q39.The alkaline earth metal nitrate that does not crystallise with molecules is: (1) 𝐵𝑎𝑁𝑂32 (2) 𝑆𝑟𝑁𝑂32 (3) 𝑀𝑔𝑁𝑂32 (4) 𝐶𝑎𝑁𝑂32

Q39.The correct order of hydration enthalpies of alkali metal ions is: (1) Na+ > Li+ > K+ > Rb+(2)>Na+Cs+> Li+ > K+ > Cs+(3)>Li+Rb+> Na+ > K+ > Rb+(4)>Li+Cs+> Na+ > K+ > Cs+ > Rb+

Q39.If Ksp of Ag2 CO3 is 8 × 10−12 , the molar solubility of Ag2 CO3 in 0 .1 M AgNO3 is: (1) 8 x 10−13M (2) 8 x 10−11M (3) 8 x 10−12M (4) 8 x 10−10M

Q40.The volume strength of 1M H2O2 is: (Molar mass of H2O2 = 34 g mol−1 ) (1) 5.6 (2) 22.4 (3) 11.2 (4) 16.8

Q42.A solution containing 62 g ethylene glycol in 250 g water is cooled to −10oC . If Kf for water is 1.86 K kg mol−1 , the amount of water (in g ) separated as ice is: (1) 48 (2) 64 (3) 16 (4) 32

Q44.The radius of the largest sphere which fits properly at the centre of the edge of a body centred cubic unit cell is : (Edge length is represented by 'a') (1) 0.027 a (2) 0.047 a (3) 0.134a (4) 0.067 a

Q44.At room temperature, a dilute solution of urea is prepared by dissolving 0.60 g of urea in 360 g of water. If the vapour pressure of pure water at this temperature is 35 mm Hg , lowering of vapour pressure will be: (molar mass of urea = 60 g mol−1 ) (1) 0.028 mm Hg (2) 0.027 mm Hg (3) 0.031 mm Hg (4) 0.017 mm Hg

Q45.Molecules of benzoic acid (C6H5 COOH) dimerise in 30 g of benzene. ' w ' g of benzoic acid shows a depression in freezing point equal to 2 K. If the percentage association of the acid to form dimer in the solution is 80, then w is: ( Given that Kf = 5 Kmol−1 , molar mass of benzoic acid = 122 gmol−1) (1) 1.0g (2) 2.4g (3) 1.8g (4) 1.5g Q46. ∧om for NaCl, HCl and NaA are 126.4, 425.9 and 100 .5 S cm2 mol−1 respectively. If the conductivity of 0 .001 M HA is 5 × 10−5S cm−1 , degree of dissociation of HA is (1) 0.125 (2) 0.75 (3) 0.25 (4) 0.50

Q45.A solid having density of 9 × 103 kg m−3 forms face centred cubic crystals of edge length 200√2pm. What is the molar mass of the solid? [Avogadro constant ≈6 × 1023 mol−1, π ≈3] (1) 0.0432 kg mol−1 (2) 0.0216 kg mol−1 (3) 0.0305 kg mol−1 (4) 0.4320 kg mol−1

Q45. K2HgI4 is 40% ionised in aqueous solution. The value of its van't Hoff factor (i) is: (1) 1.6 (2) 1.8 (3) 20 (4) 22

Q46.A solution is prepared by dissolving 0.6 g of urea (molar mass = 60 g mol−1 ) and 1.8 g of glucose (molar mass = 180 g mol−1 ) in 100 mL of water at 27oC. The osmotic pressure of the solution is: ( R = 0.08206 Latm K−1 mol−1 ) (1) 8.2 atm (2) 2.46 atm (3) 4.92 atm (4) 1.64 atm

Q46.Given the equilibrium constant: KC of the reaction: Cu(s) + 2Ag+(aq) →Cu2+(aq) + 2Ag(s) is 10 × 1015 calculate the E cell 0 of this reaction at 298 K [2.303 RTF at 298 K = 0.059 V] (1) 0.04736mV (2) 0.4736mV (3) 0.4736 V (4) 0.04736 V JEE Main 2019 (11 Jan Shift 2) JEE Main Previous Year Paper

Q47.For a reaction, consider the plot of ln k versus 1/T given in the figure. If the rate constant of this reaction at 400 K is 10−5s−1 , then the rate constant at 500 K is: JEE Main 2019 (12 Jan Shift 2) JEE Main Previous Year Paper (1) 10−4s−1 (2) 10−6s−1 (3) 2 x 10−4s−1 (4) 4 x 10−4s−1

Q47.Liquids A and B form an ideal solution in the entire composition range. At 350K, the vapour pressure of pure A and pure B are 7 × 103 Pa and 12 × 103 Pa , respectively. The composition of the vapour in equilibrium with a solution containing 40 mole percent of A at this temperature is: (1) xA = 0.4; xB = 0.6 (2) xA = 0.76; xB = 0.24 (3) xA = 0.28; xB = 0.72 (4) xA = 0.37; xB = 0.63

Q47.The reaction 2X →B is a zeroth order reaction. If the initial concentration of X is 0.2M, the half-life is 6 h. When the initial concentration of X is 0.5M, the time required to reach its final concentration of 0.2M will be (1) 9.0 h (2) 12.0 h (3) 18.0 h (4) 7.2 h

Q49.For the reaction of H2 with I2, the rate constant is 2.5 × 10-4 dm3mol-1s-1 at 327oC and 1.0 dm3 mol-1s-1 at 527°C . The activation energy for the reaction, in kJ mol-1 is: R = 8.314 JK-1mol-1 (1) 166 (2) 59 (3) 72 (4) 150

Q53.The total number of isomers for a square planar complex: [MCl(F)(NO2)(SCN)] is: (1) 12 (2) 16 (3) 4 (4) 8

Q31.A sample of NaClO3 is converted by heat to NaCl with a loss of 0. 16 g of oxygen. The residue is dissolved in water and precipitated as AgCl. The mass of AgCl (in g) obtained will be: (Given: Molar mass of AgCl = 143 .5 g mol−1 ) (1) 0. 35 (2) 0. 54 (3) 0. 41 (4) 0. 48

Q32.Ejection of the photoelectron from metal in the photoelectric effect experiment can be stopped by applying 0. 5 V , when the radiation of 250 nm is used. The work function of the metal is (1) 4 eV (2) 5. 5 eV (3) 4. 5 eV (4) 5 eV

Q40.An ideal gas undergoes a cyclic process as shown in the figure ΔUBC = −5 KJmol−1, qAB = 2 KJmol−1 WAB = −5 KJmol−1, WCA = 3 KJmol−1 Heat absorbed by the system during process CA is (1) −5 KJmol−1 (2) +5 KJmol−1 (3) −18 KJmol−1 (4) 18 KJmol−1

Q43.The minimum volume of water required to dissolve 0.1 g lead (II) chloride to get a saturated solution ( Ksp of PbCl2 = 3.2 × 10−8 ;atomic mass of Pb = 207 u ) is: (1) 1.798 L (2) 0.36 L (3) 17.98 L (4) 0.18 L

Q49.How long (approximate) should water be electrolysed by passing through 100 amperes current so that the oxygen released can completely burn 27. 66 g of diborane? (Atomic weight of B = 10. 8 u) (1) 1. 6 hours (2) 6. 4 hours (3) 0. 8 hours (4) 3. 2 hours

Q50.At 518oC, the rate of decomposition of a sample of gaseous acetaldehyde, initially at a pressure of 363 Torr was 1 .00 Torr s−1 when 5% had reacted and 0 .50 Torr s−1 when 33% had reacted. The order of the reaction is: (1) 0 (2) 2 (3) 3 (4) 1