List of top Chemistry Questions asked in JEE Main

The sum of number of lone pairs of electrons present on the central atoms of $XeO _3, XeOF _4$ and $XeF _6$ is_____

A first order reaction has the rate constant, $k =46 \times 10^{-3} s ^{-1}$ The number of correct statement/s from the following is/are _______ 
Given: $\log 3=0.48$
A. Reaction completes in $1000 \,s$
B. The reaction has a half-life of $500 \, s$ 
C. The time required for $10 \%$ completion is 25 times the time required for $90 \%$ completion 
D. The degree of dissociation is equal to $\left(1-e^{-k t}\right)$ 
E. The rate and the rate constant have the same unit

The number of statement/s, which are correct with respect to the compression of carbon dioxide from point (a) in the Andrews isotherm from the following is ______ 

A. Carbon dioxide remains as a gas upto point (b) 
B. Liquid carbon dioxide appears at point (c) 
C. Liquid and gaseous carbon dioxide coexist between points (b) and (c) 
D. As the volume decreases from (b) to (c), the amount of liquid decreases

A litre of buffer solution contains $01$ mole of each of $NH _3$ and $NH _4 CL$ On the addition of $002$ mole of $HCl$ by dissolving gaseous $HCl$, the $pH$ of the solution is found to be ____ $\times 10^{-3}$ (Nearest integer) [Given : $pK _5\left( NH _3\right)=4745$ $ \log 2=0301$ $\log 3=0477$ $T =298 K ]$

The graph of $\log \frac{x}{m}$ vs $\log p$ for an adsorption process is a straight line inclined at an angle of $45^{\circ}$ with intercept equal to $0.6020$ The mass of gas adsorbed per unit mass of adsorbent at the pressure of $04 \,atm$ is______ $\times 10^{-1}$ (Nearest integer)
Given: $\log 2=0.3010$

The strength of $50$ volume solution of hydrogen peroxide is _____$g / L$ (Nearest integer)
Given: Molar mass of $H _2 O _2$ is $34\, g \, mol ^{-1}$ Molar volume of gas at $STP =22.7\, L$

How many of the following metal ions have similar value of spin only magnetic moment in gaseous state? (Given: Atomic number: $V, 23; Cr, 24; Fe, 26; Ni, 28$) $V ^{3+} \cdot Ci ^{3+} \cdot Fe ^{2+} \cdot Ni ^{3+}$

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)

1 mole of ideal gas is allowed to expand reversibly and adiabatically from a temperature of $27^{\circ} C$ The work done is $3\, kJ \,mol ^{-1}$ The final temperature of the gas is _______ $K$ (Nearest integer).
Given $C_{ V }=20 \,J\, mol ^{-1} K ^{-1}$

An athlete is given $100\, g$ of glucose $\left( C _6 H _{12} O _6\right)$ for energy This is equivalent to $1800\, kJ$ of energy The $50 \%$ of this energy gained is utilized by the athlete for sports activities at the event In order to avoid storage of energy, the weight of extra water he would need to perspire is ___ $g$ (Nearest integer) Assume that there is no other way of consuming stored energy Given: The enthalpy of evaporation of water is $45 \,kJ \,m o l^{-1}$ Molar mass of $C H\, \&\, O$ are 12,1 and $16\, g \,mol ^{-1}$

The electrode potential of the following half cell at $298\, K$ $X \left| X ^{2+}(0.001 M ) \| Y ^{2+}(0.01 M )\right| Y$ is _____$\times 10^{-2} V$ (Nearest integer)
 Given: $E _{ x ^{2 *} \mid x }^0=-2.36\, V$ 
$ E _{ Y ^{0-1 Y }}^0=+0.36\, V$ 
$\frac{2303 RT }{ F }=0.06 \,V$

A short peptide on complete hydrolysis produces 3 moles of glycine (G), two moles of leucine $( L )$ and two moles of valine $( V )$ per mole of peptide The number of peptide linkages in it are ______

$P t(s)\left|II_2( g )(1 bar )\right| II^{+}(a q)(1 M)|| M^{3+}(a q), M^{+}(a q) \mid P t(s)$ The $E _{\text {cell }}$ for the given cell is $01115 V$ at $298 K$ when $\frac{\left[M^{+}(a q)\right]}{\left[M^{3+}(a q)\right]}=10^{\circ}$ The value of $a$ is _____ Given : $E ^\theta M ^{3+} M ^{+}=02 V$ $\frac{2303 R T}{F}=0059 V$

The number of paramagnetic species from the following is ________
$ {\left[ Ni ( CN )_4\right]^{2-} \cdot\left[ Ni ( CO )_4\right],\left[ NiCl _4\right]^{2-}} $ $ {\left[ Fe ( CN )_6\right]^{4-},\left[ Cu \left( NH _3\right)_4\right]^{2+}}$ $ {\left[ Fe ( CN )_6\right]^{3-} \text { and }\left[ Fe \left( H _2 O \right)_6\right]^{2+}}$

Number of compounds giving (i) red colouration with ceric ammonium nitrate and also (ii) positive iodoform test from the following is_____

Iron oxide $FeO$, crystallises in a cubic lattice with a unit cell edge length of $50 \mathring{A}$ If density of the $FeO$ in the crystal is $40\, g \,cm ^{-3}$, then the number of $FeO$ units present per unit cell is ______ (Nearest integer) Given: Molar mass of $Fe$ and $O$ is $56$ and $16 \, g \, mol ^{-1}$ respectively $N _{ A }=60 \times 10^{23} mol ^{-1}$

A $300\, mL$ bottle of soft drink has $0.2 \,M\, CO _2$ dissolved in it Assuming $CO _2$ behaves as an ideal gas, the volume of the dissolved $CO _2$ at STP is ______$mL$ (Nearest integer) Given : At STP, molar volume of an ideal gas is $227\, L \,mol ^{-1}$

The osmotic pressure of solutions of PVC in cyclohexanone at $300 K$ are plotted on the graph The molar mass of $PVC$ is ____$g \,mol ^{-1}$ (Nearest integer)

( Given : R = 0.083 L atm K^-1 mol^-1 )

The total number of lone pairs of electrons on oxygen atoms of ozone is _______

For the first order reaction $A \rightarrow B$, the half life is $30 min$ The time taken for $75 \%$ completion of the reaction is min (Nearest integer) Given : $\log _g 2=03010$ $ \log 3=04771 $ $ \log 5=06989$

An organic compound undergoes first order decomposition If the time taken for the \(60 \%\) decomposition is \(540 \,s\), then the time required for \(90 \%\) decomposition will be is ______ s. (Nearest integer)
(Given: \(\ln 10=2.3 ; \log 2=0.3\))

Lead storage battery contains $38 \%$ by weight solution of $H _2 SO _4$ The van't Hoff factor is $2.67$ at this concentration The temperature in Kelvin at which the solution in the battery will freeze is ______(Nearest integer) Given $K _f=1.8\, K \,kg\, mol ^{-1}$