List of top Chemistry Questions asked in JEE Main

Match the List-I with List-II :
List I Cations A→Pb2+,Cu2+ B→Al3+,Fe3+ C→Co2+,Ni2+ D→Ba2+,Ca2+ List II Group reagent i.H2S gas in presence of dilute HCl ii. (NH4)2CO3 in presence
The compound which will have the lowest rate towards nucleophilic aromatic substitution on treatment with $OH ^{-}$is
A chloride salt solution acidified with dil $HNO _3$ gives a curdy white precipitate, $[A]$, on addition of $AgNO _3 - [A]$ on treatment with $NH _4 OH$ gives a clear solution, $B$$A$ and $B$ are respectively
On complete combustion, $0.492\, g$ of an organic compound gave $0.792 \,g$ of $CO _2$ The $\%$ of carbon in the organic compound is(Nearest integer)

Which of the following compounds would give the following set of qualitative analysis?

  1. Fehling's Test: Positive
  2. Na fusion extract upon treatment with sodium nitroprusside gives a blood-red colour but not prussian blue
In sulphur estimation, $0471 \,g$ of an organic compound gave $14439 \,g$ of barium sulphate The percentage of sulphur in the compound is ___(Nearest Integer) (Grven: Atomic mass Ba: $137 \,u , S : 32\, u , O : 16 \,u$ )
The density of a monobasic strong acid (Molar mass $242 \,g$ mol) is $121 \,kg \,L$ The volume of its solution required for the complete neutralization of $25 \,mL$ of $024\, M\, NaOH$ is ___$\times 10^{-2} mL$ (Nearest integer)
The most stable carbocation for the following is:
In Dumas method for the estimation of $N _2$, the sample is heated with copper oxide and the gas evolved is passed over :
The separation of two coloured substances was done by paper chromatography The distances travelled by solvent front, substance $A$ and substance $B$ from the base line are $3.25\, cm.  2.08\, cm$ and $1.05 \,cm$. respectively. The ratio of $R_f$ values of $A$ to $B$ is ________
The ratio of silica to alumina in cement is:
Identify the correct statement about the compound GaAIC14
In the following halogenated organic compounds the one with maximum number of chlorine atoms in its structure is :
An unknown organic compound is heated with fuming \(HNO_3\). The reaction mixture is treated with aq \(BaCl_2\) solution which gives white precipitate. Identify the unknown organic compound.
During the detection of Lead, the Formation of which of the following compounds is not used as a confirmatory test.

What is the chemical formula of freon gas?

Prolonged heating of ferrous ammonium sulphate is avoided to prevent :
The separation of two coloured substances was done by paper chromatography The distances travelled by solvent front, substance $A$ and substance $B$ from the base line are $3.25\, cm.  2.08 \, cm$ and $1.05\, cm$ respectively. The ratio of $R_f$ values of $A$ to $B$ is _______
The dissociation constant of acetic acid is $x \times 10^{-5}$ When $25 \,mL$ of $0.2 \,M \,CH _3 COONa$ solution is mixed with $25 \,mL$ of $0.02\, M \,CH _3 COOH$ solution, the $pH$ of the resultant solution is found to be equal to 5. The value of $x$ is ___
\(K_{sp}\) of \(BaSO_4\) is 8 × \(10^{-11}\). If the solubility in presence of 0.1 M \(CaSO_4\) is?
$20 \,mL$ of $01 \,M \,NH _4 OH$ is mixed with $40\, mL$ of $005\, M \,HCl$ The $pH$ of the mixture is nearest to: (Given: $K _{ b }\left( NH _4 OH \right)=1 \times 10^{-5}, \log 2=030$, $\log 3=048, \log 5=069, \log 7=084$, $\log 11=104$ )
A sample of a metal oxide has formula $M _{0.83} O _{1.00}$ The metal $M$ can exist in two oxidation states $+2$ and $+3$ In the sample of $M _{0.83} O _{1.00}$, the percentage of metal ions existing in $+2$ oxidation state is___$ \%$ (nearest integer)

How many moles of Ba3(PO4)2 will be formed by the reaction of 5 moles of BaCl2 and 3 moles of Na3(PO4).

0.5 gm of an organic compound with 60%. Carbon produce ______ gm of \(CO_{2}\) upon complete combustion
The rate constant for a first order reaction is $20 \min ^{-1}$ The time required for the initial concentration of the reactant to reduce to its $\frac{1}{32}$ level is ___$\times 10^{-2} \min$ (Nearest integer) 
(Given: $\ln 10=2.303$ $\log 2=0.3010$ )