List of top Chemistry Questions asked in JEE Main

The percentage composition of carbon by mole in methane is :

The correct structure of histidine in a strongly acidic solution (pH=2) is

The structure of Nylon-6 is :

Consider the $bcc$ unit cells of the solids $1$ and $2$ with the position of atoms as shown below. The radius of atom $B$ is twice that of atom $A$. The unit cell edge length is $50\%$ more in solid $2$ than in $1$. What is the approximate packing efficiency in solid $2$ ?

${K_2HgI_4}$ is $40\%$ ionised in aqueous solution. The value of its van't Hoff factor (i) is :

If dichloromethane (DCM) and water ${(H_2O)}$ are used for differential extraction, which one of the following statements is correct ?

With respect to an ore, Ellingham diagram helps to predict the feasibility of its -

The pair that has similar atomic radii is :

Sodium metal on dissolution in liquid ammonia gives a deep blue solution due to the formation of:

For the following reactions, equilibrium constants are given : $S\left(s\right)+O_{2}\left(g\right) $${\rightleftharpoons}$$SO_{2}\left(g\right); K_{1} =10^{52}$ $2S\left(s\right)+3O_{2}\left(g\right) $${\rightleftharpoons}$$2SO_{3}\left(g\right); K_{2} = 10^{129}$ The eqilibrium constant for the reaction, $2SO_{2}\left(g\right)+O_{2}\left(g\right)$${\rightleftharpoons}$$2SO_{3}\left(g\right)$ is :

$ {Mn_2(CO)_{10}}$ is an organometallic compound due to the presence of :

A solution containing $62\, g$ ethylene glycol in $250 \,g$ water is cooled to $-10^{\circ}C$. If $K_f$ for water is $1.86\, K\, kg \,mol^{-1}$, the amount of water (in g) separated as ice is :

What would be the molality of $20\%$ (mass / mass) aqueous solution of $KI$? (molar mass of $KI = 166\, g\, mol^{-1}$)

Haemoglobin and gold sol are examples of :

The complex that has highest crystal feild splitting energy $(\Delta )$, is :

The pair that does NOT require calcination is:

Hall-Heroult's process is given by :

$C_{60}$, an allotrope of carbon contains :

Iodine reacts with concentrated ${HNO_3}$ to yield $Y$ along with other products. The oxidation state of iodine in $Y$, is :

The compound that inhibits the growth of tumors is :

NaH is an example of :

Liquids $A$ and $B$ form an ideal solution in the entire composition range. At $350\, K$, the vapor pressures of pure $A$ and pure $B$ are $7 \times 10^3$ Pa and $12 \times 10^3\, Pa$, respectively. The composition of the vapor in equilibrium with a solution containing $40$ mole percent of $A$ at this temperature is :

The metal d-orbitals that are directly facing the ligands in $ {K_3[Co(CN)_6]}$ are :

The mass of a non-volatile, non-electrolyte solute (molar mass $= 50\, g\, mol^{-1}$) needed to be dissolved in $114\, g$ octane to reduce its vapour pressure to $75\%,$ is :

For $1$ molal aqueous solution of the following compounds, which one will show the highest freezing point ?