Practice Questions
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Q60. The ratio of number of oxygen atoms to bromine atoms in the product Q is ______ ×10−1 .
Q60.The Spin only magnetic moment value of square planar complex PtNH32ClNH2CH3Cl is _______ B.M. (Nearest integer) ( Given atomic number for Pt = 78 )
Q60.Molar mass of the salt from NaBr, NaNO3, KI and CaF2 which does not evolve coloured vapours on heating with concentrated H2SO4 is ____ g mol – 1, (Molar mass in g mol – 1 : Na : 23, N : 14, K : 39, O : 16, Br : 80, I : 127, F : 19, Ca : 40 )
Q60.The total number of correct statements, regarding the nucleic acids is _________. A. RNA is regarded as the reserve of genetic information. B. DNA molecule self-duplicates during cell division C. DNA synthesizes proteins in the cell. D. The message for the synthesis of particular proteins is present in DNA E. Identical DNA strands are transferred to daughter cells.
Q60.From the compounds given below, number of compounds which give positive Fehling's test is Benzaldehyde, Acetaldehyde, Acetone, Acetophenone,Methanal, 4-nitrobenzaldehyde, cyclohexane carbaldehyde. + i = √−1 and α, β ∈R, then α + β is equal to
Q60. Xg of ethanamine was subjected to reaction with NaNO2/HCl followed by hydrolysis to liberate N2 and HCl. The HCl generated was completely neutralised by 0.2 moles of NaOH. X is ______ g. ∈C : Im and S3 = {z ∈C : Re(z) ≥0}. Then the
Q60.Vanillin compound obtained from vanilla beans, has total sum of oxygen atoms and π electrons is ______
Q60. Xg of ethylamine is subjected to reaction with NaNO2/HCl followed by water; evolved dinitrogen gas which occupied 2.24 L volume at STP. X is ×10−1 g.
Q60.The number of tripeptides formed by three different amino acids using each amino acid once is _______.
Q60.Total number of essential amino acid among the given list of amino acids is _______ Arginine, Phenylalanine, Aspartic acid, Cysteine, Histidine, Valine, Proline
Q60.The total number of carbon atoms present in tyrosine, an amino acid, is _______
Q61.If z = x + iy, xy ≠0, satisfies the equation z2 + iz = 0, then z2 is equal to : (1) 9 (2) 1 (3) 4 (4) 14
Q61.If 𝑧 is a complex number, then the number of common roots of the equation 𝑧1985 + 𝑧100 + 1 = 0 and 𝑧3 + 2𝑧2 + 2𝑧+ 1 = 0, is equal to : (1) 1 (2) 2 (3) 0 (4) 3
Q61.If 𝛼, 𝛽 are the roots of the equation, x2 - x - 1 = 0 and Sn = 2023𝛼n + 2024𝛽n, then (1) 2 S12 = S11 + S10 (2) S12 = S11 + S10 (3) 2 S11 = S12 + S10 (4) S11 = S10 + S12 4! ! 5! ( ) (
Q61.Consider the following two statements : Statement I : For any two non-zero complex numbers z1, z2 , (|z1| + |z2|) z1 + z2 ≤2 (|z1| + |z2|), and |z1| |z2| Statement II : If x, y, z are three distinct complex numbers and a, b, c are three positive real numbers such that |y−z| a = |z−x|b = |x−y|c , then y−za2 + z−xb2 + x−yc2 = 1. Between the above two statements, (1) Statement I is correct but Statement II is (2) both Statement I and Statement II are correct. incorrect. (3) both Statement I and Statement II are incorrect. (4) Statement I is incorrect but Statement II is correct.
Q61.If 2 and 6 are the roots of the equation ax2 + bx + 1 = 0, then the quadratic equation, whose roots are 2a+b1 and 1 , is : 6a+b (1) 2x2 + 11x + 12 = 0 (2) x2 + 8x + 12 = 0 (3) 4x2 + 14x + 12 = 0 (4) x2 + 10x + 16 = 0
Q61.The sum of all possible values of θ ∈[−π, 2π], for which 1−2i1+i coscosθθ is purely imaginary, is equal (1) 3π (2) 2π (3) 5π (4) 4π
Q61.The area (in sq. units) of the region S = {z ∈C : |z −1| ≤2; (z + ¯z) + i(z −¯z) ≤2, Im(z) ≥0} is (1) 7π (2) 7π 3 4 (3) 17π (4) 3π 8 2
Q62.Let 𝛼= and 𝛽= 3! )4!.! Then : 4! 5! ( ( ) ) (1) 𝛼∈N and 𝛽∉N (2) 𝛼∉N and 𝛽∈N (3) 𝛼∈N and 𝛽∈N (4) 𝛼∉N and 𝛽∉N
Q62.Let Sa denote the sum of first n terms an arithmetic progression. If S20 = 790 and S10 = 145, then S15−S5 is : JEE Main 2024 (30 Jan Shift 1) JEE Main Previous Year Paper (1) 395 (2) 390 (3) 405 (4) 410
Q31.The molality of a 10%(v/V) solution of di-bromine solution in CCl4 (carbon tetrachloride) is x '. x = _____ × 10−2M. (Nearest integer) [Given : molar mass of Br2 = 160 g mol−1 atomic mass of C = 12 g mol−1 atomic mass of Cl = 35. 5 g mol−1 density of dibromine = 3. 2 g cm−3 density of CCl4 = 1. 6 g cm−3]
Q31.Assume that the radius of the first Bohr orbit of hydrogen atom is 0. 6Å . The radius of the third Bohr orbit of He+ is _____ picometer. (Nearest Integer)
Q31.Number of hydrogen atoms per molecule of a hydrocarbon A having 85. 8% carbon is (Given : Molar mass of A = 84 g mol−1 )
Q31.An organic compound gives 0. 220 g of CO2 and 0. 126 g of H2O on complete combustion. If the % of carbon is 24 then the % of hydrogen is _________ × 10–1. (Nearest integer)
Q32.Assume carbon burns according to following equation : 2C(s) + O2( g) →2 CO (s) when 12 g carbon is burnt in 48 g of oxygen, the volume of carbon monoxide produced is ______ × 10−1 L at STP [nearest integer] [Given : Assume CO as ideal gas, Mass of C is 12 g mol−1 , mass of O is 16 g mol−1 and molar volume of an idal gas at STP is 22. 7 L mol−1 ]