List of top Chemistry Questions asked in JEE Main

$0.3\, g$ of ethane undergoes combustion at $27^{\circ} C$ in a bomb calorimeter The temperature of calorimeter system (including the water) is found to rise by $05^{\circ} C$ The heat evolved during combustion of ethane at constant pressure is ___$kJ \, mol ^{-1}$ (Nearest integer) [Given : The heat capacity of the calorimeter system is $20 \, kJ\, K ^{-1}, R =83 \, JK ^{-1}\, mol ^{-1}$ Assume ideal gas behaviour Atomic mass of $C$ and $H$ are 12 and $1\, g\, mol ^{-1}$ respectively]

Consider the following reaction that goes from A to B in three steps as shown

below Choose the correct option:

The product , which is not obtained during the electrolysis of brine solution is

$A \rightarrow B$ The rate constants of the above reaction at $200 K$ and $300 K$ are $0.03 \min ^{-1}$ and $0.05 \min ^{-1}$ respectively The activation energy for the reaction is __$J$ (Nearest integer) (Given $: \ln 10=2.3$

$R =8.3 \,JK ^{-1} \,mol ^{-1}$

$\log 5=0.70$

$\log 3=0.48$

$\log 2=0.30)$

In Carius tube, an organic compound ‘X’ is treated with sodium peroxide to form a mineral acid ‘Y’. The solution of $BaCl_2$, is added to ‘Y’ to form a precipitate ‘Z’. ‘Z’ is used for the quantitative estimation of an extra element. ‘X’ could be

Assume carbon burns according to following equation :
$2 C _{( s )}+ O _{2( g )} \rightarrow 2 CO ( g )$
When $12 g$ carbon is burnt in $48 g$ of oxygen, the volume of carbon monoxide produced is___ $\times 10^{-1} L$ at STP. [nearest integer]
[Given : Assume $CO$ as ideal gas, Mass of $C$ is $12\, g \,mol ^{-1}$, Mass of $O$ is $16 \,g \,mol ^{-1}$ and molar volume of an ideal gas at STP is $22.7\, L\, mol ^{-1}$ ]

Consider the above reaction and identify the product B.

80 mole percent of MgCl₂ is dissociated in aqueous solution. The vapour pressure of 1.0 molal aqueous solution of M_gCl₂ at 38°C is ____mm Hg. (Nearest integer)
Given : Vapour pressure of water at 38°C is 50 mm Hg.

Correct statements for the given reaction are:

A. Compound 'B' is aromatic
B. The completion of above reaction is very slow
C. 'A' shows tautomerism
D. The bond lengths C-C in compound B are found to be same
Choose the correct answer from the options given below:

Choose the correct option.

What is the major product of the following reaction?

Given below are two statements:
Statement-I: Pure Aniline and other arylamines are usually colourless.
Statement-II: Arylamines get coloured on storage due to atmospheric reduction
In the light of the above statements, choose the most appropriate answer from the options given below:

Consider the following equation: $2 SO _2(g)+ O _2(g) \rightleftharpoons 2 SO _3(g), \Delta H =-190 \,kJ$. The number of factors which will increase the yield of $SO _3$ at equilibrium from the following is _______
A. Increasing temperature
B. Increasing pressure
C. Adding more $SO _2$
D. Adding more $O _2$ E Addition of catalyst

The compound which does not exist.

The correct increasing order of the ionic radii is

Gibbs energy vs T plot for the formation of oxides is given below.

For the given diagram, the correct statement is -

A cubic solid is made up of two elements $X$ and $Y$ Atoms of $X$ are present on every alternate corner and one at the enter of cube $Y$ is at $\frac{1}{3} td$ of the total faces The empirical formula of the compound is

Find correct order of covalent character (A) $KF < KI$ (B) $CuCl > NaCl$ (C) $LiF > KF$

Match List I with List II

LIST I		LIST II
A	Chlorophyll	1	$Na _2 CO _3$
B	Soda ash	2	$CaSO _4$
C	Dentistry, Ornamental work	3	$Mg ^{2+}$
D	Used in white washing	4	$Ca ( OH )_2$

Compound A reacts with $NH _4 Cl$ and forms a compound B Compound B reacts with $H _2 O$ and excess of $CO _2$ to form compound $C$ which on passing through or reaction with saturated $NaCl$ solution forms sodium hydrogen carbonate Compound $A , B$ and $C$, are respectively

Given below are two statements, one is labelled as Assertion $A$ and the other is labeled as Reason $R$
Assertion A : The alkali metals and their salts impart characteristic colour to reducing flame
Reason R : Alkali metals can be detected using flame tests
In the light of the above statements, choose the most appropriate answer from the options given below

Which one among the following metals is the weakest reducing agent?

Compound A reacts with $NH _4 Cl$ and forms a compound B.

Compound B reacts with $H _2 O$ and excess of $CO _2$ to form compound $C$ which on passing through or reaction with saturated $NaCl$ solution forms sodium hydrogen carbonate Compound $A , B$ and $C$, are respectively.

The total number of acidic oxides from the following list is: $NO , N _2 O , B _2 O _3, N _2 O _5$, $CO , SO _3, P _4 O _{10}$

Match List I with List II

LIST I		LIST II
A	X_eF₄	I	See-saw
B	SF₄	II	Square planar
C	NH₄+	III	Bent T-shaped
D	BrF₃	IV	Tetrahedral

Choose the correct answer from the options given below :