JEE Main entrance exam Question Bank Solutions for Chemistry (JEE Main)

Low oxidation state of metals in their complexes are common when ligands ______.

Which will have the highest enol content?

Seliwanoff test and Xanthoproteic test are used for the identification of ______ and ______ respectively.

	\[\ce{CH2 = \overset{⊕}{C}H}\]	\[\ce{CH3 - \overset{⊕}{C}H2}\]	\[\ce{HC ≡ \overset{⊕}{C}}\]
A	B	C	D

The correct order of stability of given carbocation is:

A solution of (–) – 1 – chloro–1–phenylethane in toluene racemises slowly in the presence of a small amount of SbCl₅, due to the formation of ______.

The increasing order of stability of the following free radicals is ______.

In a hydrogen-oxygen fuel cell, combustion of hydrogen occurs to ______.

In general, the property (magnitudes only) that shows an opposite trend in comparison to other properties across a period is ______. 

Compound A is converted to B on reaction with CHCl₃ and KOH. The compound B is toxic and can be decomposed by C. A, B and C respectively are ______.

Consider the elements Mg, Al, S, P and Si, the correct increasing order of their first ionization enthalpy is ______.

The correct order of intensity of colors of the compounds is ______.

An inorganic compound 'X' on treatment with concentrated H₂SO₄ produces brown fumes and gives a dark brown ring with FeSO₄ in presence of concentrated H₂SO₄. Also, compound 'X' gives precipitate 'Y', when its solution in dilute HCl is treated with H₂S gas. The precipitate 'Y' on treatment with concentrated HNO₃ followed by an excess of NH₄OH further gives a deep blue coloured solution, compound 'X' is:

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

1. Both the complexes can be high spin.
2. Ni(II) complex can very rarely below spin.
3. With strong field Ligands, Mn(II) complexes can be low spin.
4. Aqueous solution of Mn (II) ions is yellow in colour.

The correct statements are:

The major product in the following reaction is:

Consider that d⁶ metal ion (M²⁺) 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 are ______.

The acceptable resonating structures of the following molecule are:

\[\begin{array}{cc}
\ce{CH3 - CH = C - \overset{\bullet\bullet}{\underset{\bullet\bullet}{O}} - CH2 - CH3}\\
|\phantom{......}\\
\ce{:N}\phantom{.......}\\
\phantom{}/\phantom{...}\backslash\phantom{......}\\
\phantom{}\ce{H3C}\phantom{.....}\ce{CH3}\phantom{......}
\end{array}\]

Isocyanide reaction involves the intermediate formation of ______.

For the gaseous reaction, \[\ce{K_{(g)} + F_{(g)} -> K^+_{ (g)} + F^-_{ (g)}}\], ΔH was calculated to be 19 kcal/mol under conditions where the cations and anions were prevented by electrostatic separation from combining with each other. The ionisation energy of K is 4.3 eV. The electron affinity of F is ______. (in eV)

The lassaigne's extract is boiled with dil. HNO₃ before testing for halogens because ______.

If the starting material is 1-methyl-1,2-epoxy cyclopentane, of absolute configuration, decide which one compound correctly represents the product of its reaction with sodium methoxide in methanol.