List of top Chemistry Questions asked in JEE Main

Addition of phosphate fertilisers to water bodies causes :

In the long form of the periodic table, the valence shell electronic configuration of $5s^2 5p^4$ corresponds to the element present in :

The least number of oxyacids are formed by :

In the presence of peroxide, $HCl$ and $HI$ do not give anti-Markownikoff' s addition to alkenes because :

Considering the basic strength of amines in aqueous solution, which one has the smallest $pK_b$ value?

Conversion of benzene diazonium chloride to chloro benzene is an example of which of the following reactions ?

Which one of the following molecules is paramagnetic ?

Amongst $LiCl, RbCl, BeCl_2$ and $MgCl_2$ the compounds with the greatest and the least ionic character, respectively are :

Tischenko reaction is a modification of :

For the compounds $CH_3Cl, \, CH_3Br,\,CH_3I$ and $CH_3F,$ the correct order of increasing $C$-halogen bond length is :

In S$_N$2 reactions, the correct order of reactivity for the following compounds $CH_3Cl,CH_3CH_2Cl, (CH_3 )_2CHCl$ and (CH$_3 )_3CCl$ is

The most suitable reagent for the conversion of $RCH_2OH \to RCHO$ is

In the Victor-Meyer's test, the colour given by $1^{\circ}$, $2^{\circ}$and $3^{\circ}$ alcohols are respectively :

Which one of the following substituents at para-position is most effective in stabilizing the phenoxide ion ?

Which one of the following compounds will not be soluble in sodium bicarbonate?

Chloro compound of Vanadium has only spin magnetic moment of $1.73\, BM$. This Vanadium chloride has the formula : (at. no. of $V = 23$)

Among the following organic acids, the acid present in rancid butter is :

Which of the following will not show mutarotation?

Which one of the following acids does not exhibit optical isomerism?

Assuming that the degree of hydrolysis is small, the pH of 0.1 M solution of sodium acetate $(K_a = 1.0 \times 10^{-5})$ will be :

At a certain temperature, only $50\%$ $HI$ is dissociated into $H_2$ and $I_2$ at equilibrium. The equilibrium constant is :

What happens when an inert gas is added to an equilibrium keeping volume unchanged ?

The amount of $BaSO _{4}$ formed upon mixing $100 \,mL$ of $20.8 \% BaCl _{2}$ solution with $50 \,mL$ of $9.8 \% H _{2} SO _{4}$ solution will be : $( Ba =137, Cl =35.5, S =32, H =1$ and $O =16)$

For the complete combustion of ethanol, $C_2H_5OH_{(l)} + 3O_{2(g)} \rightarrow 2CO_{2(g)} + 3H_2O_{(l)},$ the amount of heat produced as measured in bomb calorimeter, is $1364.47 \,kJ \,moI^{-1}$ at $25^{\circ}$C. Assuming ideality the enthalpy of combustion, $\Delta_ CH$, for the reaction will be $(R = 8.314\, J \,K^{-1}$ $mol^{-1})$

Choose the correct statement with respect to the vapour pressure of a liquid among the following :