iit jee previous years questions chapter wise Archives

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Chemistry, Previous Years Chapterwise Questions

JEE Main Previous Year Papers Questions of Chemistry With Solutions are available at eSaral.

Simulator

Previous Years AIEEE/JEE Mains Questions

Q. The IUPAC name of neopentane is :-

(1) 2–methylpropane

(2) 2, 2–dimethylbutane

(3) 2–methylbutane

(4) 2, 2–dimethylpropane

[AIEEE -2009]

Sol. (4)

Q. The IUPAC name of the compound is :-

(1) 1, 2-Epoxy propane

(2) Propylene oxide

(3) 1, 2–Oxo propane

(4) 1, 2–Propoxide

[AIEEE -2012(online]

Sol. (1)

Hydrocarbons – JEE Main Previous Year Questions with Solutions

By eSaral

3 Comments

August 30, 2019

1050 Views

Chemistry, Previous Years Chapterwise Questions

JEE Main Previous Year Papers Questions of Chemistry With Solutions are available at eSaral.

Simulator

Previous Years AIEEE/JEE Mains Questions

Q. The main product of the following reaction is

[AIEEE-2010]

Sol. (2)

Q. One mole of a symmetrical alkene on ozonolysis gives two moles of an aldehyde having a molecular mass of 44 u. The alkene is :-

(1) Ethene

(2) Propene

(3) 1-Butene

(4) 2-Butene

[AIEEE-2010]

Sol. (4)

Q. Ozonolysis of an organic compound gives formaldehyde as one of the products. This confirms the presence of :-

(1) an isopropyl group

(2) an acetylenic triple bond

(3) two ethylenic double bonds

(4) a vinyl group

[AIEEE-2011]

Sol. (4)

Q. Ozonolysis of an organic compound ‘A’ produces acetone and propionaldehyde in equimolar mixture. Identify ‘A’ from the following compounds :-

(1) 2-Methyl-1-pentene

(2) 1-Pentene

(3) 2-Pentene

(4) 2-Methyl-2-pentene

[AIEEE-2011]

Sol. (4)

Q. 2–Hexyne gives trans–2–Hexene on treatment with :-

[AIEEE-2012]

Sol. (3)

Q. In the given transformation, which of the following is the most appropriate reagent ?

[AIEEE-2012]

Sol. (2)

Q. The major organic compound formed by the reaction of 1, 1, 1–trichloroethane with silver powder is :-

(1) 2-Butyne

(2) 2-Butene

(3) Acetylen

(4) Ethene

[Jee-Main offline 2013]

Sol. (1)

Q. The number and type of bonds in $\mathrm{C}_{2}^{2-}$ ion in $\mathrm{CaC}_{2}$ are:

(1) Two $\sigma$ bonds and one $\pi$ – bond

(2) Two $\sigma$ bonds and two $\pi$ – bonds

(3) One $\sigma$ bond and two $\pi$ – bonds

(4) One $\sigma$ bond and one $\pi-$ bond

[Jee-Main offline 2014]

Sol. (3)

$\mathrm{Ca}^{+2}[\mathrm{C} \equiv \mathrm{C}]^{-2}$

Q. In the hydroboration – oxidation reaction of propene with diborane, $\mathrm{H}_{2} \mathrm{O}_{2}$ and NaOH, the organic compound formed is :

(1) $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OH}$

( 2)$\left(\mathrm{CH}_{3}\right)_{3} \mathrm{COH}$

(3) $\mathrm{CH}_{3} \mathrm{CHOHCH}_{3}$

(4) $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}$

[Jee-Main offline 2014]

Sol. (1)

Q. Which one of the following class of compounds is obtained by polymerization of acetylene ?

(1) Poly-ene

(2) Poly-yne

(3) Poly-amide

(4) Poly-ester

[Jee-Main offline 2014]

Sol. (2)

Q. The gas liberated by the electrolysis of Dipotassium succinate solution is :

(1) Ethyne

(2) Ethene

(3) Propene

(4) Ethane

[Jee-Main offline 2014]

Sol. (2)

Q. The reagent needed for converting

(1) $\mathrm{H}_{2} /$ lindlar Cat.

(2) Cat. Hydrogenatio

(4) LiNH $_{3}$

[Jee-Main offline 2014]

Sol. (4)

on mercuration- demercuration produces the major product :-

[Jee-Main offline 2014]

Sol. (1)

Rearrangement of carbocation formed is not possible due to formatiion of cyclic non-classical carbocation.

Q. The major product obtained in the photo catalysed bromination of 2-methylbutane is :-

(1) 2-bromo-2-methylbutane

(2) 2-bromo-3-methylbutane

(3) l-bromo-2-methylbutane

(4) l-bromo-3-methylbutane

[Jee-Main offline 2014]

Sol. (1)

Q. In the presence of peroxide, HC and HI do not give anti-Markownikoff s addition to alkenes because

(1) All the steps are exothermic in HCl and HI

(2) One of the steps is endothermic in HCl and HI

(3) HCl is oxidizing and the HI is reducing

(4) Both HCl and HI are strong acids

[Jee-Main offline 2014]

Sol. (2)

relectivity ratio for bromination is

$1^{\circ}: 2^{\circ}: 3^{\circ}: 1: 82: 1600$

Hence $3^{\circ}$ product will be major product.

Q. Which compound would give 5-keto-2-methyl hexanal upon ozonlysis?

[Jee-Main offline 2015]

Sol. (4)

Q. The trans-alkenes are formed by the reduction of alkynes with :

(1) $\mathrm{NaBH}_{4}$

(2) Na/liq. NH $_{3}$

(3) Sn–HCl

(4) $\mathrm{H}_{2}-\mathrm{Pd} / \mathrm{C}, \mathrm{BaSO}_{4}$

[Jee-Main offline 2018]

Sol. (2)

Birch reduction is anti addition. So trans alkene will be produced.

Hydrogen – JEE Main Previous Year Questions with Solutions

By eSaral

3 Comments

August 29, 2019

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Chemistry, Previous Years Chapterwise Questions, Uncategorized

JEE Main Previous Year Papers Questions of Chemistry With Solutions are available at eSaral.

Simulator

Previous Years AIEEE/JEE Mains Questions

Q. Very pure hydrogen (99.9%) can be made by which of the following processes?

(1) Reaction of salt like hydrides with water

(2) Reaction of methane with steam

(3) Mixing natural hydrocarbons of high molecular weight

(4) Electrolysis of water

[AIEEE 2012]

Sol. (4)

Very pure hydrogen (99.9%) can be made by electrolysis of water.

Q. In which of the following reaction $\mathrm{H}_{2} \mathrm{O}_{2}$ acts as a reducing agent ?

(1) (1), (3)

(2) (2), (4)

(3) (1), (2)

(4) (3), (4)

[JEE(Main) 2014]

Sol. (2)

When $\mathrm{H}_{2} \mathrm{O}_{2}$ act as reducing agent then it evolve.

Q. Which of the following statements about $\mathrm{Na}_{2} \mathrm{O}_{2}$ is not correct ?

(1) $\mathrm{Na}_{2} \mathrm{O}_{2}$ oxidises $\mathrm{Cr}^{3+}$ to $\mathrm{CrO}_{4}^{2-}$ in acid medium

(2) It is diamagnetic in nature

(3) It is the super oxide of sodium

(4) It is a derivative of $\mathrm{H}_{2} \mathrm{O}_{2}$

[JEE(Main) 2014]

Sol. (3)

$\mathrm{Na}_{2} \mathrm{O}_{2}$ is peroxide of sodium

Q. Hydrogen peroxide acts both as an oxidising and as a reducing agent depending upon the nature of the reacting species. In which of the following cases $\mathrm{H}_{2} \mathrm{O}_{2}$ acts as a reducing agent in acid medium ? :-

(1) $\mathrm{MnO}_{4}^{-}$

(2) $\mathrm{SO}_{3}^{2-}$

(3) KI

(4) $\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}$

[JEE(Main)Online-2014]

Sol. (1)

Q. Permanent hardness in water cannot be cured by:

(1) Treatment with washing soda

(2) Calgon’s method

(3) Boiling

(4) Ion exchange method

[JEE(Main)Online-2015]

Sol. (3)

Permanent hardness in water cannot cured by boiling of water

Q. From the following statements regarding H2O2, choose the incorrect statement :

(1) It has to be stored in plastic or wax lined glass bottles in dark

(2) It has to be kept away from dust

(3) It can act only as an oxidizing agent

(4) It decomposes on exposure to light

[JEE(Main)Online-2015]

Sol. (3)

$\mathrm{H}_{2} \mathrm{O}_{2}$ can act as oxidizing as well as reducing agent depend on condition.

Q. Hydrogen peroxide oxidises $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}$ to $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{3-}$ in acidic medium but reduces

$\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{3-}$ to $\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{4-}$ in alkaline

medium. The other products formed are, respectively :

[JEE(Main)Online-2018]

(1) $\left(\mathrm{H}_{2} \mathrm{O}+\mathrm{O}_{2}\right)$ and $\left(\mathrm{H}_{2} \mathrm{O}+\mathrm{OH}^{-}\right)$

(2) $\mathrm{H}_{2} \mathrm{O}$ and $\left(\mathrm{H}_{2} \mathrm{O}+\mathrm{O}_{2}\right)$

(3) $\mathrm{H}_{2} \mathrm{O}$ and $\left(\mathrm{H}_{2} \mathrm{O}+\mathrm{OH}^{-}\right)$

(4) $\left(\mathrm{H}_{2} \mathrm{O}+\mathrm{O}_{2}\right)$ and $\mathrm{H}_{2} \mathrm{O}$

Sol. (2)