List of top Questions asked in JEE Main- 2019

The ore that contains the metal in the form of fluoride is :

Match the catalysts (Column I) with products (Column II).

Column I	Column II
(A) \(\mathrm{V_2O_5}\)	(i) Polyethylene
(B) \(\mathrm{TiCl_4/Al(Me)_3}\)	(ii) ethanal
(C) \(\mathrm{PdCl_2}\)	(iii) \(\mathrm{H_2SO_4}\)
(D) Iron Oxide	(iv) \(\mathrm{NH_3}\)

Excessive release of \(\mathrm{CO_2}\) into the atmosphere results in :

The osmotic pressure of a dilute solution of an ionic compound XY in water is four times that of a solution of 0.01 M \(\mathrm{BaCl_2}\) in water. Assuming complete dissociation of the given ionic compounds in water, the concentration of XY (in mol \(\mathrm{L^{-1}}\)) in solution is :

Aniline dissolved in dilute HCl is reacted with sodium nitrite at \(0^\circ\mathrm{C}\). This solution was added dropwise to a solution containing equimolar mixture of aniline and phenol in dil. HCl. The structure of the major product is

The major product of the following reaction is :
\(\mathrm{CH_3-C\equiv CH}\ \xrightarrow[\mathrm{(ii)\ DI}]{\mathrm{(i)\ DCl\ (1\ equiv.)}}\)

Magnesium powder burns in air to give :

The increasing order of reactivity of the following compounds towards aromatic electrophilic substitution reaction is :

The one that will show optical activity is :
(en = ethane-1,2-diamine)

The major product of the following reaction is :

For any given series of spectral lines of atomic hydrogen, let \(\Delta\bar{\nu} = \Delta\bar{\nu}_{max} - \Delta\bar{\nu}_{min}\) be the difference in maximum and minimum frequencies in \(\mathrm{cm^{-1}}\). The ratio \(\dfrac{\Delta\bar{\nu}_{Lyman}}{\Delta\bar{\nu}_{Balmer}}\) is :

The standard Gibbs energy for the given cell reaction in kJ mol^-1 at 298 K is :
\(\mathrm{Zn(s) + Cu^{2+}(aq) \rightarrow Zn^{2+}(aq) + Cu(s)}\),
\(E^\circ = 2\ \mathrm{V}\) at 298 K
(Faraday's constant, \(F = 96000\ \mathrm{C\ mol^{-1}}\))

Which of the following statements is not true about sucrose?

The major product of the following reaction is :

The given plots represent the variation of the concentration of a reactant R with time for two different reactions (i) and (ii). The respective orders of the reactions are :

The organic compound that gives following qualitative analysis is :

	Test	Inference
(a)	Dil. HCl	Insoluble
(b)	NaOH solution	soluble
(c)	\(\mathrm{Br_2}\)/water	Decolourization

Among the following, the molecule expected to be stabilized by anion formation is :
\(\mathrm{C_2,\ O_2,\ NO,\ F_2}\)

The degenerate orbitals of \([\mathrm{Cr(H_2O)_6}]^{3+}\) are :

Liquid 'M' and liquid 'N' form an ideal solution. The vapour pressures of pure liquids 'M' and 'N' are 450 and 700 mmHg, respectively, at the same temperature. Then correct statement is:
(\(x_M\) = Mole fraction of 'M' in solution ;
\(x_N\) = Mole fraction of 'N' in solution ;
\(y_M\) = Mole fraction of 'M' in vapour phase ;
\(y_N\) = Mole fraction of 'N' in vapour phase)

The major product of the following reaction is :

A signal \(A\cos\omega t\) is transmitted using \(v_0\sin\omega_0 t\) as carrier wave. The correct amplitude modulated (AM) signal is

The major product of the following reaction is :
\(\mathrm{CH_3CH=CHCO_2CH_3}\ \xrightarrow{\ \mathrm{LiAlH_4}\ }\ ?\)

An NPN transistor is used in common emitter configuration as an amplifier with \(1\ \mathrm{k}\Omega\) load resistance. Signal voltage of 10 mV is applied across the base-emitter. This produces a 3 mA change in the collector current and \(15\mu\mathrm{A}\) change in the base current of the amplifier. The input resistance and voltage gain are :

The total number of turns and cross-section area in a solenoid is fixed. However, its length \(L\) is varied by adjusting the separation between windings. The inductance of solenoid will be proportional to :

A capacitor with capacitance \(5\mu\mathrm{F}\) is charged to \(5\mu\mathrm{C}\). If the plates are pulled apart to reduce the capacitance to \(2\mu\mathrm{F}\), how much work is done ?