List of top Chemistry Questions asked in JEE Main

For the disproportionation reaction
\(\mathrm{2Cu^+(aq) \rightleftharpoons Cu(s) + Cu^{2+}(aq)}\) at 298 K. \(\ln K\) (where K is the equilibrium constant) is ___________ \(\times 10^{-1}\).
Given : ( \(E^0_{\mathrm{Cu^{2+}/Cu^+}} = 0.16\) V, \(E^0_{\mathrm{Cu^+/Cu}} = 0.52\) V, \(\dfrac{RT}{F} = 0.025\) )

Two elements A and B have similar chemical properties. They don’t form solid hydrogencarbonates, but react with nitrogen to form nitrides. A and B, respectively, are :

Amongst the following statements regarding adsorption, those that are valid are

(a) \(\Delta H\) becomes less negative as adsorption proceeds
(b) On a given adsorbent, ammonia is adsorbed more than nitrogen gas
(c) On adsorption, the residual force acting along the surface of the adsorbent increases
(d) With increase in temperature, the equilibrium concentration of adsorbate increases

The ratio of the mass percentages of ‘C & H’ and ‘C & O’ of a saturated acyclic organic compound ‘X’ are 4 : 1 and 3 : 4 respectively. Then, the moles of oxygen gas required for complete combustion of two moles of organic compound ‘X’ is ________.

The work function of sodium metal is \(4.41 \times 10^{-19}\) J. If photons of wavelength 300 nm are incident on the metal, the kinetic energy of the ejected electrons will be (h = \(6.63 \times 10^{-34}\) J s; c = \(3 \times 10^{8}\) m/s) ________ \(\times 10^{-21}\) J.

The molecular geometry of \(\mathrm{SF_6}\) is octahedral. What is the geometry of \(\mathrm{SF_4}\) (including lone pair(s) of electrons, if any)?

Three elements X, Y and Z are in the 3^rd period of the periodic table. The oxides of X, Y and Z, respectively, are basic, amphoteric and acidic. The correct order of the atomic numbers of X, Y and Z is :

The results given in the below table were obtained during kinetic studies of the following reaction
\(2A + B \to C + D\)

Experiment	[A]/mol L-1	[B]/mol L-1	Initial rate/mol L-1 min-1
I	0.1	0.1	\(6.00 \times 10^{-3}\)
II	0.1	0.2	\(2.40 \times 10^{-2}\)
III	0.2	0.1	\(1.20 \times 10^{-2}\)
IV	X	0.2	\(7.20 \times 10^{-2}\)
V	0.3	Y	\(2.88 \times 10^{-1}\)

X and Y in the given table are respectively :

If you spill a chemical toilet cleaning liquid on your hand, your first aid would be

The one that is not expected to show isomerism is :

Match the type of interaction in column A with the distance dependence of their interaction energy in column B

A	B
(i) ion-ion	(a) \(\frac{1}{r}\)
(ii) dipole-dipole	(b) \(\frac{1}{r^2}\)
(iii) London dispersion	(c) \(\frac{1}{r^3}\)
	(d) \(\frac{1}{r^6}\)

The size of a raw mango shrinks to a much smaller size when kept in a concentrated salt solution. Which one of the following processes can explain this?

The number of subshells associated with \(n = 4\) and \(m = -2\) quantum numbers is

The mass of gas adsorbed, x, per unit mass of adsorbate, m, was measured at various pressures, p. A graph between \(\log \frac{x}{m}\) and \(\log p\) gives a straight line with slope equal to 2 and the intercept equal to 0.4771. The value of \(\frac{x}{m}\) at a pressure of 4 atm is :
(Given \(\log 3 = 0.4771\))

The internal energy change (in J) when 90 g of water undergoes complete evaporation at \(100^\circ\mathrm{C}\) is ____________.
(Given : \(\Delta H_{vap}\) for water at 373 K = 41 kJ/mol, \(R = 8.314\ \mathrm{J\,K^{-1}\,mol^{-1}}\))

The metal mainly used in devising photoelectric cells is :

The Gibbs change (in J) for the given reaction at [Cu²⁺] = [Sn²⁺] = 1 M and 298 K is :
Cu(s) + Sn²⁺(aq.) \(\to\) Cu²⁺(aq.) + Sn(s);
(\(E^0_{\mathrm{Sn^{2+}|Sn}} = -0.16\) V, \(E^0_{\mathrm{Cu^{2+}|Cu}} = 0.34\) V)
Take F = 96500 C mol^-1

Which of the following is used for the preparation of colloids?

On heating compound (A) gives a gas (B) which is a constituent of air. This gas when treated with H₂ in the presence of a catalyst gives another gas (C) which is basic in nature. (A) should not be :

The statement that is not true about ozone is :

If AB₄ molecule is a polar molecule, a possible geometry of AB₄ is

For octahedral Mn(II) and tetrahedral Ni(II) complexes, consider the following statements:

(I) both the complexes can be high spin.
(II) Ni(II) complex can very rarely be low spin.
(III) with strong field ligands, Mn(II) complexes can be low spin.
(IV) aqueous solution of Mn(II) ions is yellow in colour.

The correct statements are :

While titrating dilute HCl solution with aqueous NaOH, which of the following will not be required?

An open beaker of water in equilibrium with water vapour is in a sealed container. When a few grams of glucose are added to the beaker of water, the rate at which water molecules :

Consider that a \(\mathrm{d^6}\) metal ion (\(\mathrm{M^{2+}}\)) forms a complex with aqua ligands, and the spin only magnetic moment of the complex is 4.90 BM. The geometry and the crystal field stabilization energy of the complex is