Other Chemistry · JEE Main previous year questions

1. A.
2. B.
3. C.
4. D.

Choose the polar molecule from the following:

1. A.$\mathrm{CC}{\mathrm{l}}_4$
2. B.$\mathrm{C}{\mathrm{O}}_2$
3. C.$\mathrm{C}{\mathrm{H}}_2=\mathrm{C}{\mathrm{H}}_2$
4. D.$\mathrm{CHC}{\mathrm{l}}_3$

Yellow compound of lead chromate gets dissolved on treatment with hot $\text{NaOH}$ solution. The product of lead formed is a :

1. A.Tetraanionic complex with coordination number six
2. B.Neutral complex with coordination number four
3. C.Dianionic complex with coordination number six
4. D.Dianionic complex with coordination number four

$\text{NaCl}$ reacts with conc. ${\text{H}}_2{\text{SO}}_4$ and ${\text{K}}_2{\text{Cr}}_2{\text{O}}_7$ to give reddish fumes (B), which react with $\text{NaOH}$ to give yellow solution (C). (B) and (C) respectively are ;

1. A.${\text{CrO}}_2{\text{Cl}}_2,{\text{Na}}_2{\text{CrO}}_4$
2. B.${\text{Na}}_2{\text{CrO}}_4,{\text{CrO}}_2{\text{Cl}}_2$
3. C.${\text{CrO}}_2{\text{Cl}}_2,{\text{KHSO}}_4$
4. D.${\text{CrO}}_2{\text{Cl}}_2,{\text{Na}}_2{\text{Cr}}_2{\text{O}}_7$

The mass of silver (Molar mass of $\text{Ag}:108{\text{ gmol}}^{-1}$) displaced by a quantity of electricity which displaces $5600\text{ mL}$ of ${\text{O}}_2$ at S.T.P. will be _____ $\text{g}$.

Mass of methane required to produce $22\text{ g}$ of ${\text{CO}}_2$ after complete combustion is _______ $\text{g}$. (Given Molar mass in $\text{g mol-1 C}=12.0$, $\text{H}=1.0$, $\text{O}=16.0$)

Among the following, total number of meta directing functional groups is (Integer based) $-{\text{OCH}}_3,-{\text{NO}}_2,-\text{CN},-{\text{CH}}_3,-{\text{NHCOCH}}_3,-\text{COR},-\text{OH},-\text{COOH},-\text{Cl}$

Identify the incorrect pair from the following :

1. A.Haber process - $\text{Iron}$
2. B.Polythene preparation - ${\text{TiCl}}_4,{\text{Al(CH}}_3{)}_3$
3. C.Photography - $\text{AgBr}$
4. D.Wacker process - ${\text{PtCl}}_2$

1. A.
2. B.
3. C.
4. D.

1. A.(B) and (C) only
2. B.(A), (B) and (D) only
3. C.(B) only
4. D.(A) and (B) only

1. A.
2. B.
3. C.
4. D.

The quantity which changes with temperature is :

1. A.Molality
2. B.Molarity
3. C.Mole fraction
4. D.Mass percentage

Volume of $3\text{M NaOH}$ (formula weight $40{\text{ g mol}}^{-1}$ ) which can be prepared from $84\text{ g}$ of $\text{NaOH}$ is _______ $\times 10^{-1}{\text{dm}}^3$.

${\mathrm{ClF}}_5$ at room temperature is a:

1. A.Colourless liquid with square pyramidal geometry
2. B.Colourless gas with square pyramidal geometry
3. C.Colourless gas with trigonal bipyramidal geometry.
4. D.Colourless liquid with trigonal bipyramidal geometry

2-Methyl propyl bromide reacts with ${\mathrm{C}}_2{\mathrm{H}}_5{\mathrm{O}}^{-}$ and gives 'A' whereas on reaction with ${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$ it gives 'B'. The mechanism followed in these reactions and the products 'A' and 'B' respectively are :

1. A.${\mathrm{S}}_{N}1$, $A=\text{tert-butyl ethyl ether}$; ${\mathrm{S}}_{N}2$, $B=\text{iso-butyl ethyl ether}$
2. B.${\mathrm{S}}_{N}1$, $A=\text{tert-butyl ethyl ether}$; ${\mathrm{S}}_{N}1$, $\mathrm{B}=\text{2-butyl ethyl ether}$
3. C.${\mathrm{S}}_{N}2$, $\mathrm{A}=\text{iso-butyl ethyl ether}$; ${\mathrm{S}}_{N}1$, $\mathrm{B}=\text{tert-butyl ethyl ether}$
4. D.${\mathrm{S}}_{N}2$, $\mathrm{A}=\text{2-butyl ethyl ether}$; ${\mathrm{S}}_{N}2$, $\mathrm{B}=\text{iso-butyl ethyl ether}$

What happens when a lyophilic sol is added to a lyophobic sol?

1. A.Film of lyophobic sol is formed over lyophilic sol.
2. B.Lyophilic sol is dispersed in lyophobic sol.
3. C.Film of lyophilic sol is formed over lyophobic sol.
4. D.Lyophobic sol is coagulated

Which one of the following is most likely a mismatch ?

1. A.Titanium - van Arkel Method
2. B.Zinc - Liquation
3. C.Nickel - Mond process
4. D.Copper - Electrolysis

The incorrect statement from the following for borazine is :

1. A.It can react with water.
2. B.It is a cyclic compound.
3. C.It has electronic delocalization.
4. D.It contains banana bonds.

${\mathrm{Be}(\mathrm{OH})}_2$ reacts with ${\mathrm{Sr}(\mathrm{OH})}_2$ to yield an ionic salt. Choose the incorrect option related to this reaction from the following :

1. A.$\mathrm{Be}$ is tetrahedrally coordinated in the ionic salt.
2. B.The element $\mathrm{Be}$ is present in the cationic part of the ionic salt.
3. C.Both $\mathrm{Sr}$ and $\mathrm{Be}$ elements are present in the ionic salt.
4. D.The reaction is an example of acid - base neutralization reaction.

1. A.Both A and R are correct but R is NOT the correct explanation of A
2. B.A is false but R is true
3. C.A is true but R is false
4. D.Both A and R are correct and R is the correct explanation of A

Better method for preparation of ${\mathrm{BeF}}_2$, among the following is :

1. A.${\mathrm{BeH}}_2+{\mathrm{F}}_2\stackrel{\Delta }{\to }{\mathrm{BeF}}_2$
2. B.$({\mathrm{NH}}_4{)}_2{\mathrm{BeF}}_4\stackrel{\Delta }{\to }{\mathrm{BeF}}_2$
3. C.$\mathrm{Be}+{\mathrm{F}}_2\stackrel{\Delta }{\to }{\mathrm{BeF}}_2$
4. D.$\mathrm{BeO}+\mathrm{C}+{\mathrm{F}}_2\stackrel{\Delta }{\to }{\mathrm{BeF}}_2$

See the following chemical reaction: $${\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}+{\mathrm{XH}}^{+}+6{\mathrm{Fe}}^{2+}\to {\mathrm{YCr}}^{3+}+6{\mathrm{Fe}}^{3+}+{\mathrm{ZH}}_2\mathrm{O}$$ The sum of X, Y and Z is ___________

$1\text{ g}$ of a carbonate $({\mathrm{M}}_2{\mathrm{CO}}_3)$ on treatment with excess $\mathrm{HCl}$ produces $0.01\text{ mol}$ of ${\mathrm{CO}}_2$. The molar mass of ${\mathrm{M}}_2{\mathrm{CO}}_3$ is ___________ ${\text{g mol}}^{-1}$. (Nearest integer)

$\text{2-hexene}\underset{(\mathrm{ii}){\mathrm{H}}_2\mathrm{O}}{\overset{(\mathrm{i}){\mathrm{O}}_3}{\to }}\text{Products}$ The two products formed in above reaction are -

1. A.Butanal and acetaldehyde
2. B.Butanoic acid and acetic acid
3. C.Butanal and acetic acid
4. D.Butanoic acid and acetaldehyde

1. A.'B' is N-nitroso ammonium compound
2. B.The product 'B' formed in the above reaction is p-nitroso compound at low temperature
3. C.The electrophile involved in the reaction is $\mathrm{N}{\mathrm{O}}^{+}$
4. D.The reaction occurs at low temperature