Haloalkanes & Haloarenes · JEE Main previous year questions

Consider two radiations of wavelengths 1. ${\lambda }_1=2000\text{A˚}$ 2. ${\lambda }_2=6000\text{A˚}$ The ratio of the energies of these two radiations $\left(\frac{{\mathrm{E}}_1}{{\mathrm{E}}_2}\right)$ is ____. (Nearest integer).

Given below are two statements : Statement I : ${\text{F}}_2\text{O}<{\text{H}}_2\text{O}<{\text{Cl}}_2\text{O}$ is the correct trend in terms of bond angle. Statement II : ${\text{SiF}}_4$, ${\text{SnF}}_4$ and ${\text{PbF}}_4$ are ionic in nature. In the light of the above statements, choose the correct answer from the options given below :

1. A.Both Statement I and Statement II are true
2. B.Both Statement I and Statement II are false
3. C.Statement I is true but Statement II is false
4. D.Statement I is false but Statement II is true

Match the LIST-I with LIST-II $$\begin{array}{llll}& \text{List-I}& & \text{List-II}\\ & \text{Name of reaction}& & \text{Reagent or catalyst used}\\ \text{A.}& \text{Finkelstein reaction}& \text{I.}& \mathrm{Sb}{\mathrm{F}}_3\\ \text{B.}& \text{Swarts reaction}& \text{II.}& \mathrm{Na}\text{, dry ether}\\ \text{C.}& \text{Sandmeyer’s reaction}& \text{III.}& \mathrm{NaI}\\ \text{D.}& \text{Fittig reaction}& \text{IV.}& \mathrm{C}{\mathrm{u}}_2\mathrm{C}{\mathrm{l}}_2\end{array}$$ Choose the correct answer from the options given below:

1. A.A-I, B-IV, C-III, D-II
2. B.A-III, B-I, C-IV, D-II
3. C.A-IV, B-II, C-I, D-III
4. D.A-I, B-III, C-II, D-IV

Correct statements regarding alkyl halides ($\mathrm{R}-\mathrm{X}$) among the following are : A. Alcohol being less polar solvent as compared to water, alcoholic $\mathrm{KOH}$ favours elimination reaction with $\mathrm{R}-\mathrm{X}$. B. Order of reactivity towards ${\mathrm{S}}_{\mathrm{N}}^1$ mechanism is ${\mathrm{C}}_6{\mathrm{H}}_5-\mathrm{C}{\mathrm{H}}_2-\mathrm{Cl}>{\mathrm{C}}_6{\mathrm{H}}_5-\mathrm{CHCl}-{\mathrm{C}}_6{\mathrm{H}}_5$. C. Non substituted aryl halides exhibit properties similar to alkyl halides. D. Vinyl chloride is an example of haloalkene and allyl chloride is an example of haloalkyne. E. $\mathrm{R}-\mathrm{Cl}$ can be prepared by reacting $\mathrm{R}-\mathrm{OH}$ with $\mathrm{SOC}{\mathrm{l}}_2$ but $\mathrm{Ar}-\mathrm{Cl}$ cannot be prepared by reacting $\mathrm{Ar}-\mathrm{OH}$ with $\mathrm{SOC}{\mathrm{l}}_2$. Choose the correct answer from the options given below :

1. A.A, B and C Only
2. B.B and D Only
3. C.A and E Only
4. D.D and E Only

Identify the INCORRECT statements from the following : A. Notation ${}_{12}^{24}\text{Mg}$ represents 24 protons and 12 neutrons. B. Wavelength of a radiation of frequency $4.5\times 10^{15}{\text{ s}}^{-1}$ is $6.7\times 10^{-8}\text{ m}$. C. One radiation has wavelength $={\lambda }_1(900\text{ nm})$ and energy $={\text{E}}_1$. Other radiation has wavelength $={\lambda }_2(300\text{ nm})$ and energy $={\text{E}}_2$. ${\text{E}}_1:{\text{E}}_2=3:1$. D. Number of photons of light of wavelength 2000 pm that provides 1 J of energy is $1.006\times 10^{16}$. Choose the correct answer from the options given below :

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

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

1. A.Both Statement I and Statement II are incorrect
2. B.Both Statement I and Statement II are correct
3. C.Statement I is correct but Statement II is incorrect
4. D.Statement I is incorrect but Statement II is correct

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

Given below are two statements : Statement (I) : ${\mathrm{S}}_{\mathrm{N}}2$ reactions are 'stereospecific', indicating that they result in the formation of only one stereo-isomer as the product. Statement (II) : ${\mathrm{S}}_{\mathrm{N}}1$ reactions generally result in formation of product as racemic mixtures. In the light of the above statements, choose the correct answer from the options given below :

1. A.Both Statement I and Statement II are false
2. B.Statement I is false but Statement II is true
3. C.Statement I is true but Statement II is false
4. D.Both Statement I and Statement II are true

Match List - I with List - II. | List I (Compound) | List II (Use) | | :--- | :--- | | (A) Carbon tetrachloride | (I) Paint remover | | (B) Methylene chloride | (II) Refrigerators and air conditioners | | (C) DDT | (III) Fire extinguisher | | (D) Freons | (IV) Non Biodegradable insecticide | Choose the correct answer from the options given below :

1. A.(A)-(II), (B)-(III), (C)-(I), (D)-(IV)
2. B.(A)-(III), (B)-(I), (C)-(IV), (D)-(II)
3. C.(A)-(I), (B)-(II), (C)-(III), (D)-(IV)
4. D.(A)-(IV), (B)-(III), (C)-(II), (D)-(I)

Alkyl halide is converted into alkyl isocyanide by reaction with

1. A.$\mathrm{KCN}$
2. B.$\mathrm{N}{\mathrm{H}}_4\mathrm{CN}$
3. C.$\mathrm{NaCN}$
4. D.$\mathrm{AgCN}$

The correct statement regarding nucleophilic substitution reaction in a chiral alkyl halide is ;

1. A.Retention occurs in $S_{N}1$ reaction and inversion occurs in $S_{N}2$ reaction.
2. B.Racemisation occurs in $S_{N}1$ reaction and retention occurs in $S_{N}2$ reaction.
3. C.Racemisation occurs in both $S_{N}1$ and $S_{N}2$ reactions.
4. D.Racemisation occurs in $S_{N}1$ reaction and inversion occurs in $S_{N}2$ reaction.

$\mathrm{KCl}{\mathrm{O}}_3+6FeS{\mathrm{O}}_4+3{\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4\to \mathrm{KCl}+3F{\mathrm{e}}_2(\mathrm{S}{\mathrm{O}}_4{)}_3+3{\mathrm{H}}_2\mathrm{O}$ The above reaction was studied at $300\text{ K}$ by monitoring the concentration of $\mathrm{FeS}{\mathrm{O}}_4$ in which initial concentration was $10\text{M}$ and after half an hour became $8.8\text{ M}$. The rate of production of $\mathrm{F}{\mathrm{e}}_2(\mathrm{S}{\mathrm{O}}_4{)}_3$ is ________ $\times 10^{-6}{\text{ mol L}}^{-1}{\text{ s}}^{-1}$ (Nearest integer)

Solid fuel used in rocket is a mixture of $\mathrm{F}{\mathrm{e}}_2{\mathrm{O}}_3$ and $\mathrm{Al}$ (in ratio $1:2$). The heat evolved ($\text{kJ}$) per gram of the mixture is _________. (Nearest integer) Given: $\Delta {\mathrm{H}}_f^{\theta }(\mathrm{A}{\mathrm{l}}_2{\mathrm{O}}_3)=-1700{\text{ kJ mol}}^{-1}$ $\Delta {\mathrm{H}}_f^{\theta }(\mathrm{F}{\mathrm{e}}_2{\mathrm{O}}_3)=-840{\text{ kJ mol}}^{-1}$ Molar mass of $\mathrm{Fe}$, $\mathrm{Al}$ and $\mathrm{O}$ are $56$, $27$ and $16{\text{ g mol}}^{-1}$ respectively.

Which of the following compounds is an example of Freon?

1. A.${\mathrm{C}}_2{\mathrm{H}}_2{\mathrm{F}}_2$
2. B.${\mathrm{C}}_2\mathrm{H}{\mathrm{F}}_3$
3. C.${\mathrm{C}}_2{\mathrm{F}}_4$
4. D.${\mathrm{C}}_2\mathrm{C}{\mathrm{l}}_2{\mathrm{F}}_4$

1. A.$\mathrm{C}>\mathrm{A}>\mathrm{D}>\mathrm{B}$
2. B.$\mathrm{D}>\mathrm{B}>\mathrm{A}>\mathrm{C}$
3. C.$\mathrm{A}>\mathrm{B}>\mathrm{D}>\mathrm{C}$
4. D.$\mathrm{D}>\mathrm{C}>\mathrm{B}>\mathrm{A}$

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Ketoses give Seliwanoff's test faster than Aldoses. Reason (R) : Ketoses undergo $\beta$-elimination followed by formation of furfural. In the light of the above statements, choose the correct answer from the options given below :

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

1. A.A - IV, B - II, C - III, D - I
2. B.A - II, B - I, C - IV, D - III
3. C.A - II, B - I, C - III, D - IV
4. D.A - III, B - II, C - IV, D - I

Which of the following is true about freons?

1. A.These are radicals of chlorine and chlorine monoxide
2. B.These are chemicals causing skin cancer
3. C.All radicals are called freons
4. D.These are chlorofluorocarbon compounds

A solution of $\mathrm{F}{\mathrm{e}}_2(\mathrm{S}{\mathrm{O}}_4{)}_3$ is electrolyzed for 'x' min with a current of $1.5\mathrm{A}$ to deposit $0.3482\mathrm{g}$ of Fe. The value of x is ____. [nearest integer] Given : $1\mathrm{F}=96500\mathrm{C}\mathrm{mo}{\mathrm{l}}^{-1}$ Atomic mass of $\mathrm{Fe}=56\mathrm{g}\mathrm{mo}{\mathrm{l}}^{-1}$

In the given chemical reaction, colors of the $\mathrm{F}{\mathrm{e}}^{2+}$ and $\mathrm{F}{\mathrm{e}}^{3+}$ ions, are respectively : $$5{\mathrm{Fe}}^{2+}+{\mathrm{MnO}}_4^{-}+8{\mathrm{H}}^{+}\to {\mathrm{Mn}}^{2+}+4{\mathrm{H}}_2\mathrm{O}+5{\mathrm{Fe}}^{3+}$$

1. A.Yellow, Orange
2. B.Yellow, Green
3. C.Green, Orange
4. D.Green, Yellow

1. A.$(\mathrm{IV})>(\mathrm{II})>(\mathrm{III})>(\mathrm{I})$
2. B.$(\mathrm{II})>(\mathrm{III})>(\mathrm{IV})>(\mathrm{I})$
3. C.$(\mathrm{II})>(\mathrm{III})>(\mathrm{I})>(\mathrm{IV})$
4. D.$(\mathrm{III})>(\mathrm{II})>(\mathrm{IV})>(\mathrm{I})$

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

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

1. A.(B) < (A) < (D) < (C)
2. B.(A) < (B) < (C) < (D)
3. C.(A) < (B) < (D) < (C)
4. D.(B) < (A) < (C) < (D)