Practice Questions

Q59.The decomposition of formic acid on gold surface follows first order kinetics. If the rate constant at 300 K is 1. 0 × 10−3 s−1 and the activation energy Ea = 11. 488 kJ mol−1 , the rate constant at 200 K is _________ ×10−5 s−1 . (Round of to the Nearest Integer). (Given R = 8. 314 J mol−1 K−1 )

Q59.For the first order reaction A →2 B, 1 mole of reactant A gives 0. 2 moles of B after 100 minutes. The half life of the reaction is ...... min. (Round off to the nearest integer). [Use : ln 2 = 0. 69, ln 10 = 2. 3 Properties of logarithms : ln xy = y ln x = ln x −ln y] ln( xy ) (Round off to the nearest integer) Q60. 3 moles of metal complex with formula Co(en)2 Cl3 gives 3 moles of silver chloride on treatment with excess of silver nitrate. The secondary valency of Co in the complex is (Round off to the nearest integer)

Q59.The sum of oxidation states of two silver ions in AgNH32Ag ( CN ) 2 complex is _____ .

Q59.The total number of unpaired electrons present in the complex K3[Cr(oxalate)3] is______.

Q59.Among the following allotropic forms of sulphur, the number of allotropic forms, which will show paramagnetism is _______. (A) α -sulphur (B) β -sulphur (C) S2 -form JEE Main 2021 (24 Feb Shift 2) JEE Main Previous Year Paper

Q59.CH4 is adsorbed on 1 g charcoal at 0°C following the Freundlich adsorption isotherm. 10 . 0 mL of CH4 is adsorbed at 100 mm of Hg, whereas 15 . 0 mL is adsorbed at 200 mm of Hg . The volume of CH4 adsorbed at 300 mm of Hg is 10x mL . The value of x is _________ × 10-2 . (Nearest integer) [Use log102 = 0 . 3010, log103 = 0 . 4771]

Q60.The total number of unpaired electrons present in [Co(NH3)6]Cl2 and [Co(NH3)6]Cl3 is ¯

Q60.Three moles of AgCl get precipitated when one mole of an octahedral co-ordination compound with empirical formula CrCl3 . 3NH3 . 3H2O reacts with excess of silver nitrate. The number of chloride ions satisfying the secondary valency of the metal ion is ______ .

Q60.The number of geometrical isomers possible in triamminetrinitrocobalt (III) is X and in trioxalatochromate (III) is Y. Then the value of X + Y is ____.

Q60.A reaction of 0.1 mole of Benzylamine with bromomethane gave 23 g of Benzyl trimethyl ammonium bromide. The number of moles of bromomethane consumed in this reaction are n × 10−1, when n =_____ (Round off to the Nearest Integer). (Given : Atomic masses : C : 12. 0 u, H : 1. 0 u, N : 14. 0 u, Br : 80. 0 u)

Q60.Among the following, the number of halide(s) which is/ are inert to hydrolysis is (A) BF3 (B) SiCl4 (C) PCl5 (D) SF6

Q60.In Tollen's test for aldehyde, the overall number of electron(s) transferred to the Tollen's reagent formula [Ag (NH3)2]+ per aldehyde group to form silver mirror is ___.(Round off to the Nearest integer)

Q60.The reaction of white phosphorus on boiling with alkali in inert atmosphere resulted in the formation of product A. The reaction 1 mol of A with excess of AgNO3 in aqueous medium gives ________ mole(s) of Ag. (Round off to the Nearest Integer).

Q60.On complete reaction of FeCl3 with oxalic acid in aqueous solution containing KOH, resulted in the formation of product A . The secondary valency of Fe in the product A is ______ . (Round off to the Nearest Integer).

Q60.The number of stereo isomers possible for [Co (ox)2(Br)(NH3)]2− is __________. [ ox = oxalate] JEE Main 2021 (26 Feb Shift 2) JEE Main Previous Year Paper

Q60.An aqueous solution of NiCl2 was heated with excess sodium cyanide in presence of strong oxidizing agent to form [Ni(CN)6]2−. The total change in number of unpaired electrons on metal centre is ___________.

Q60.The number of optical isomers possible for [Cr (C2O4)3]3− is:

Q60.The total number of reagents from those given below, that can convert nitrobenzene into aniline is __________ . (Integer answer) I. Sn −HCl II. Sn −NH4 OH JEE Main 2021 (31 Aug Shift 1) JEE Main Previous Year Paper III. Fe −HCl IV. Zn −HCl V. H2 −Pd VI. H2− Raney Nickel

Q60.The equivalents of ethylene diamine required to replace the neutral ligands from the coordination sphere of the trans-complex of CoCl3. 4 NH3 is _______ . (Round off to the Nearest Integer).

Q60.The total number of amines among the following which can be synthesized by Gabriel synthesis is ________.

Q60.A metal surface is exposed to 500 nm radiation. The threshold frequency of the metal for photoelectric current is 4. 3 × 1014 Hz . The velocity of ejected electron is ___ × 105 ms−1 (Nearest integer) [Use : h = 6. 63 × 10−34 Js, me = 9. 0 × 10−31 kg] p and q are roots of the equation : + = + i)100 299(p iq), then

Q60.Number of electrons present in 4f orbital of Ho3+ ion is ________ (Given Atomic No. of Ho =67)

Q60.The number of nitrogen atoms in a semicarbazone molecule of acetone is_____

Q61.Let α and β be the roots of x2 −6x −2 = 0. If an = αn −βn for n ⩾1, then the value of a10−2a83a9 is: (1) 1 (2) 3 (3) 2 (4) 4

Q61.Let a complex number be w = 1 −√3i . Let another complex number z be such that |zw| = 1 and arg(z) −arg(w) = π2 . Then the area of the triangle (in sq. units) with vertices origin, z and w is equal to (1) 4 (2) 12 (3) 1 (4) 2 4