List of top Chemistry Questions asked in JEE Main

Alkali metal from the following with least melting point is:

Testosterone, which is a steroidal hormone, has the following structure

The total number of asymmetric carbon atoms in testosterone is ___

Among following compounds, the number of those present in copper matte is ___ .
$CuCO _3$
$Cu _2 S$
$Cu _2 O$
$FeO$

Among the following, the number of tranquilizer/s is/are ___
A. Chloroliazepoxide
B. Veronal
C. Valium
D. Salvarsan

A metal M crystallizes into two lattices :- face centred cubic (fcc) and body centred cubic (bcc) with unit cell edge length of 20 and $25 \,\mathring{A}$ respectively The ratio of densities of lattices fcc to bcc for the metal M is ___(Nearest integer)

$20 \%$ of acetic acid is dissociated when its $5\, g$ is added to $500 \, mL$ of water The depression in freezing point of such water is ____ $\times 10^{-3}{ }^{\circ} C$Atomic mass of $C , H$ and $O$ are 12,1 and 16 amu respectively [Given : Molal depression constant and density of water are $186 \,K \,kg\, mol ^{-1} and \ 1 \,g \,cm ^{-3}$respectively

The spin only magnetic moment of$\left[ Mn \left( H _2 O \right)_6\right]^{2+}$ complexes is ____ BM (Nearest integer) (Given: Atomic no of $Mn$ is 25 )

The molality of a 10% (v/v) solution of di-bromine solution in $\text{CCl}_4$ (carbon tetrachloride) is $x$. $x = \, \_\_\_\_\ \times 10^{-2} \, \text{M}$. (Nearest integer)
Given:
Molar mass of $\text{Br}_2 = 160 \, \text{g mol}^{-1}$
Atomic mass of $\text{C} = 12 \, \text{g mol}^{-1}$
Atomic mass of $\text{Cl} = 35.5 \, \text{g mol}^{-1}$
Density of dibromine = $3.2 \, \text{g cm}^{-3}$
Density of $\text{CCl}_4 = 1.6 \, \text{g cm}^{-3}$

The complex cation which has two isomers is :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A): $\alpha$-halocarboxylic acid on reaction with dil $NH _3$ gives good yield of $\alpha$-aminocarboxylic acid whereas the yield of amines is very low when prepared from alkyl halides
Reason (R): Amino acids exist in zwitter ion form in aqueous medium
In the light of the above statements, choose the correct answer from the options given below :

The correct order of bond enthalpy $\left( kJ mol ^{-1}\right)$ is :

The industrial activity held least responsible for global warming is :

All structures given below are of vitamin $C$ Most stable of them is :

'X' is:

$O - O$ bond length in $H _2 O _2$ is X than the $O - O$ bond length in $F _2 O _2$The $O - H$ bond length in $H _2 O _2$is Y than that of the$O - F$ bond in $F _2 O _2$Choose the correct option for $\underline{X} and \underline{Y}$ from those given below :

The graph which represents the following reaction is :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A) : An aqueous solution of $KOH$ when used for volumetric analysis, its concentration should be checked before the use
Reason (R) : On aging,$KOH$ solution absorbs atmospheric $CO _2$
In the light of the above statements, choose the correct answer from the options given below :

Which element is not present in Nessler's reagent?

In figure, a straight line is given for Freundrich Adsorption$(y=3 x+2505)$ The value of $\frac{1}{ n }$and$\log K$are respectively

Benzyl isocyanide can be obtained by:

Choose the correct answer from the options given below:

In the wet tests for identification of various cations by precipitation, which transition element cation doesn’t belong to group IV in qualitative inorganic analysis?

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): In expensive scientific instruments, silica gel is kept in watch-glasses or in semipermeable membrane bags.
Reason (R): Silica gel adsorbs moisture from air via adsorption, thus protects the instrument from water corrosion (rusting) and/or prevents malfunctioning.
In the light of the above statements, choose the correct answer from the options given below:

Which of the following compounds would give the following set of qualitative analysis?
• (i) Fehling’s Test: Positive
• (ii) Na fusion extract upon treatment with sodium nitroprusside gives a blood red colour but not

For $\text{OF}_2$ molecule consider the following:
[(A)] Number of lone pairs on oxygen is 2.
[(B)] F--O--F angle is less than $104.5^\circ$.
[(C)] Oxidation state of O is $-2$.
[(D)] Molecule is bent ‘V’-shaped.
[(E)] Molecular geometry is linear.
Correct options are:

To inhibit the growth of tumours, identify the compounds used from the following:
(A) EDTA
(B) Coordination Compounds of Pt
(C) D – Penicillamine
(D) Cis – Platin
Choose the correct answer from the options given below: