List of top Questions asked in JEE Main- 2020

Let y = y(x) be the solution curve of the differential equation,

\( \left( {{y^2} - x} \right){{dy} \over {dx}} = 1 \), satisfying y(0) = 1. This curve intersects the x-axis at a point whose abscissa is :

The refining method used when the metal and the impurities have low and high melting temperatures, respectively, is :

The area (in sq. units) of the region
{(x, y) \( \in \) R² | 4x² \( \le \) y \( \le \) 8x + 12} is :

If the function ƒ defined on \( \left( { - {1 \over 3},{1 \over 3}} \right) \) by

f(x) = \( \left\{ {\matrix{ {{1 \over x}{{\log }_e}\left( {{{1 + 3x} \over {1 - 2x}}} \right),} & {when\,x \ne 0} \cr {k,} & {when\,x = 0} \cr } } \right. \)

is continuous, then k is equal to_______.

Identify the correct labels of A,B and C in the following graph from the options given below :

Root mean square speed (V_rms); most probable speed (V_mp); Average speed (V_av)

In the following reaction, products (A) and (B) respectively, are :

NaOH + Cl₂ \( \to \) (A) + side products
(hot and conc.)

Ca(OH)₂ + Cl₂ \( \to \) (B) + side products (dry)

The number of sp² hybridised carbons present in "Aspartame" is

In the following reaction sequence,

The major product B is :

The ammonia (NH₃) released on quantitative reaction of 0.6 g urea (NH₂CONH₂) with sodium hydroxide (NaOH) can be neutralized by :

A chromatography column, packed with silica gel as stationary phase, was used to separate a mixture of compounds consisting of (A) benzanilide (B) aniline and (C) acetophenone. When the column is eluted with a mixture of solvents, hexane : ethylacelate (20:80), the sequence of obtained compounds is :

Consider the following reactions :

Which of these reactions are possible ?

For the following reactions

K_s and K_e, are respectively, the rate constants for substitution and elimination and \( \mu = {{{k_s}} \over {{k_e}}} \) the correct options is

The equation that is incorrect is :

For the reaction
2H₂(g) + 2NO(g) \( \to \) N₂(g) + 2H₂O(g)
the observed rate expression is, rate = K_f[NO]²[H₂]. The rate expression for the reverse reaction is :

The redox reaction among the following is :

Which of the following statements is correct ?

The number of possible optical isomers for the complexes MA₂B₂ with sp³ and dsp² hydridized metal atom. respectively, is :
Note : A and B are unidentate netural and unidentate monoanionic ligands, respectively.

Consider the following reactions :

\( NaCl{\rm{ }} + {\rm{ }}{K_2}C{r_2}{O_7} + \mathop {{H_2}S{O_4}}\limits_{(conc.)} \)\( \to \) (A) + side products

(A) + NaOH \( \to \) (B) + Side products

\( \left( B \right){\rm{ }} + \mathop {{H_2}S{O_4}}\limits_{(dilute)} + {\rm{ }}{H_2}{O_2} \) \( \to \) (C) + Side products

The sum of the total number of atoms in one molecule each of (A) and (B) and (C) is

The correct order of stability for the following alkoxides is :

The bond order and the magnetic characteristics of CN^- are :

3 g of acetic acid is added to 250 mL of 0.1 M HCL and the solution made up to 500 mL. To 20 mL of this solutions \( {1 \over 2} \) mL of 5 M NaOH is added. The pH of the solution is __________.

[Given : pKa of acetic acid = 4.75, molar mass of acetic of acid = 60 g/mol, log 3 = 0.4771] Neglect any changes in volume.

The standard heat of formation \( \left( {{\Delta _f}H_{298}^0} \right) \) of ethane (in kj/mol), if the heat of combustion of ethane, hydrogen and graphite are - 1560, -393.5 and -286 Kj/mol, respectively is :

The flocculation value of HCl for arsenic sulphide sol.
is 30 m mol L^-1 If H₂SO₄ is used for the flocculatiopn of arsenic sulphide, the amount in grams, of H₂SO₄ in 250 ml required for the above purposed is ______.
(molecular mass of H₂SO₄ = 98 g/mol)

Within each pair of elements F & Cl, S & Se, and Li & Na, respectively, the elements that release more energy upon and electron gain are :

Among the statements(a)-(d) the incorrect ones are :
(a) Octahedral CO(III) complexes with strong fields ligands have very high magnetic moments.
(b) When \( \Delta \)₀ < P, the d-electron configuration of Co(III) in an octahedral complex is \( t_{eg}^4e_g^2 \)
(c) Wavelength of light absorbed by [Co(en)₃]³⁺ is lower than that of [CoF₆]^3-
(d) If the \( \Delta \)₀ for an octahedral complex of CO(III) is 18,000 cm^-1, the \( \Delta \)_t for its tetrahedral complex with the same ligand be 16,000 cm^-1