Practice Questions

Q47.The magnitude of work done by a gas that undergoes a reversible expansion along the path ABC shown in the figure is _________. JEE Main 2020 (08 Jan Shift 1) JEE Main Previous Year Paper

Q48.An oxidation-reduction reaction in which 3 electrons are transferred has a ΔG0 of 17. 37 kJ mol−1 at 25°C. The value of Eocell (in V) is _______ ×10−2 . (1F = 96500 C mol−1)

Q49.The oxidation states of transition metal atoms in K2 Cr2 O7, KMnO4 and K2 FeO4, respectively, are x, y and z . The sum of x, y and z is______ JEE Main 2020 (02 Sep Shift 2) JEE Main Previous Year Paper

Q49.The volume (in mL ) of 0. 1 N NaOH required to neutralise 10 mL of 0. 1 N phosphinic acid is ____________.

Q49.The total number of coordination sites in ethylenediaminetetraacetate ( EDTA4− ) is ...................

Q50.The number of chiral centres present in threonine is _________

Q31.What would be the molality of 20% (mass/mass) aqueous solution of KI ? (molar mass of KI = 166 g mol−1 ) (1) 1.35 (2) 1.51 (3) 1.08 (4) 1.48

Q31.The percentage composition of carbon by mole in methane is: (1) 75 % (2) 20 % (3) 80 % (4) 25 % Q32.0.27 g of a long chain fatty acid was dissolved in 100 cm3 of hexane. 10 mL of this solution was added dropwise to the surface of water in a round watch glass. Hexane evaporates and a monolayer is formed. The distance from edge to centre of the watch glass is 10 cm . What is the height of the monolayer? [Density of fatty acid = 0.9 g cm-3; π = 3] (1) 10-4 m (2) 10-6 m (3) 10-8 m (4) 10-2 m

Q32.In general, the properties that decrease and increase down a group in the periodic table, respectively, are : (1) Atomic radius and electronegativity (2) Electronegativity and atomic radius (3) Electronegativity and electron gain enthalpy (4) Electron gain enthalpy and electronegativity

Q32.The size of the iso-electronic species Cl- , Ar and Ca2 + is affected by: (1) nuclear charge (2) azimuthal quantum (3) electron –electron (4) Principal quantum number of valence interaction in the outer number of valence shell orbitals shell

Q32.The electrons are more likely to be found: (1) Only in the region a (2) In the region a and b (3) In the region a and c (4) Only in the region c

Q32.The type of hybridization and no. of lone pair(s) of electron of Xe in XeOF4 , respectively, are: (1) sp3d2 and 1 (2) sp3d2 and 2 (3) sp3d and 2 (4) sp3d and 1

Q32.Among the following, the energy of 2s orbital is lowest in: JEE Main 2019 (12 Apr Shift 2) JEE Main Previous Year Paper (1) K (2) H (3) Na (4) Li

Q32.The element with Z = 120 (not yet discovered) will be a/an (1) transition metal. (2) alkaline earth metal. (3) alkali metal. (4) inner-transition metal.

Q33.The process with negative entropy change is: (1) Synthesis of ammonia from N2 and H2 . (2) Dissolution of iodine in water. (3) Dissociation of CaSO4 (s) to CaO (s) and (4) Sublimation of dry ice. SO3 (g).

Q33.When the first electron gain enthalpy (ΔHeg) of oxygen is −141 kJ/mol , its second electron gain enthalpy is: (1) A positive value (2) Almost the same as that of the first (3) Negative, but less negative than the first (4) A more negative value than the first

Q33.Aluminium is usually found in +3 oxidation state. In contrast, thallium exists in +1 and +3 oxidation states. This is due to: (1) Diagonal relationship (2) Lattice effect (3) Lanthanoid contraction (4) Inert pair effect

Q33.The correct option with respect to the Pauling electronegativity values of the elements is: (1) Te > Se (2) Ga < Ge (3) Si < Al (4) P > S

Q33.The isoelectronic set of ions is: (1) F−, Li+, Na+ and Mg2+ (2) N3−, Li+, Mg2+ and O2− (3) N3−, O2−, F− and Na+ (4) Li+, Na+, O2− and F−

Q33.The group number, number of valence electrons, and valency of an element with atomic number 15, respectively, are: (1) 15,6 and 2 (2) 16,6 and 3 (3) 16,5 and 2 (4) 15,5 and 3

Q33.The element that does not show catenation is (1) Sn (2) Si (3) Ge (4) Pb

Q33.The correct order of the atomic radii of C, Cs, Al, and S is: (1) C < S < A1 < Cs (2) S < C < Cs < Al (3) S < C < Al < Cs (4) C < S < Cs < Al

Q34.The IUPAC symbol for the element with atomic number 119 would be: (1) Unh (2) Uun (3) Une (4) Uue

Q34.The incorrect match in the following is: (1) ΔG0 < 0, K > 1 (2) ΔG0 > 0, K < 1 (3) ΔG0 = 0, K = 1 (4) ΔG0 < 0, K < 1

Q34.A process has ΔH = 200 J mol−1 and ΔS = 40 JK −1mol−1. Out of the values given below choose the minimum temperature above which the process will be spontaneous: (1) 20 K (2) 5K (3) 12K (4) 4K