Fsc part 2 Online Preparation for Chemistry Chapter 10 (Alkhl Halidies)

Question # 1

Write down the main factors on which reactivity of Alkyl halides depends.

Ans 1: There are two main factors which govern the reactivity of R-X bond.
C-X bonds: Strength of bond in compound would be the most reactive one while fluro compound will be the least reactive.
C-X bond polarity:The greatest electronegativity difference between carbon and fluorine atoms in alkyl fluorides,If an electrophile is the attaching reagent then this difference suggest that alkyl fluorides would be the most reactive alkyl halides.

Question # 2

Reaction of ethyl bromide with OH nucleophile is S_n2 justify?

Ans 1: In nucleophilic substitution bimolecular the direction of attack of OH^-,the attaching nucleophile is from the side which is opposite to the leaving group ,in order to give to the nucleophile enough room to attack on ethyl bromide the substrate carbon atom changes its state of hybridization from tetrahedral.

Question # 3

During S_n1 reaction,What is the significance of first step?

Ans 1: The first step involved the breakage of a covalent bond so it is slow step as compared to the second step which involve the energetically favourable combination of ions,the first step is therefore called the rate determining step.The mechanism step is called unimolecular because only one molecule take part in the rate determining step.

Question # 4

Explain terms Leaving Group and Electrophile.

Ans 1: Leaving group:leaving group is nucleophile which leave during substitution reaction of alkyl halide,It departs with an unshared pair of electron If we wish a S_nreaction to proceed in the forward direction the incoming nucleophile must be stronger than the departing one,CI,Br,I are goof nucleophile as well as a goof leaving group.
Electrophile: It is a specie which attracts electrons.The carbon atom of an alkyl group attaches with the halogen atom and bearing a partial positive charged is called an electrophile center,An electrophile may be neutral or positively charged.

Question # 5

What is Grignard reagent ?How it is prepared?

Ans 1: R-Mg-X known as Grignard reagent ,These are derivatives of alkyl halided belonging to class of organo metallic compounds .Grignard reagent was first prepared by Victor Grignard in 1900. Grignard reagent is so important in organic synthesis that almost all the classes of organic compounds can be prepared from them,Due to their importance and organic compounds can be prepared from them.

Question # 6

What is the natural of C-mg bond in R-mg-X?

Ans 1: The reactivity of Grignard reagent is due to the nature of C-mg bond which is highly polar, Magnesium is more electropositive than carbons and the C-mg bond though covalent is highly polar ,giving alkyl carbons the partial negative charge,This negative charge is unusual character which makes the alkyl group highly reactive towards electrophile center.

Question # 7

Why does SN₂mechanism give a product with inversion of configuration?

Ans 1: In nucleophilic substitution bimolecular the direction of attack of the attaching nucleophile is from the side which is opposite to the leaving group .In order to give the the nucleophile enough room to attack ,the substrate carbon atom changes it state of hybridization from tetrahedral to planner sp².

Question # 8

What is the role of stability of carbonium ion in deciding the Mechanism of substitution reaction.

Ans 1: The first step involve the breakage of covalent bond so it is slow step as compared to the second step which involves the energetically favourable combination of ions.The first step is therefore called the rate determining step.The mechanism is called unimolecular because one molecule takes part in the rate determining step.

Question # 9

What are b-elimination reaction?

Ans 1: When nucleophile attacks on hydrogen atom attached to the beta carbon of the alkyl halide,we get an alkene ,such type of reaction are called elimination reaction .In E1 mechanism the first step is the slow ionization of the substrate to give a carbocation.In the second step the nucleophile attacks on hydrogen to give an alkene as a product.

Question # 10

What are primary and tertiary Alkyl Halides?

Ans 1: In a primary alkyl halide halogen atom is attached with carbon which is further attached to one or more carbon atom.In a tertiary alkyl halide halogen atom is attached with a carbon which is further attached to three carbon atom.

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Fsc part 2 Online Preparation for Chemistry Chapter 10 (Alkhl Halidies)

Online Short Questions For Chapter 10 "12th Class Chemistry Chapter 10 Short Questions Preparation "

Chemistry - 12th Class Chemistry Chapter 10 Short Questions Preparation

Write down the main factors on which reactivity of Alkyl halides depends.

Reaction of ethyl bromide with OH nucleophile is Sn2 justify?

During Sn1 reaction,What is the significance of first step?

Explain terms Leaving Group and Electrophile.

What is Grignard reagent ?How it is prepared?

What is the natural of C-mg bond in R-mg-X?

Why does SN2mechanism give a product with inversion of configuration?

What is the role of stability of carbonium ion in deciding the Mechanism of substitution reaction.

What are b-elimination reaction?

What are primary and tertiary Alkyl Halides?

Prepare Complete Set Wise Questions For Chapter 10 "12th Class Chemistry Chapter 10 Short Questions Preparation "

Set 1

Set 2

12th Class Chemistry Chapter 10 Short Questions Preparation - Set 1

Write down the main factors on which reactivity of Alkyl halides depends.

Reaction of ethyl bromide with OH nucleophile is Sn2 justify?

During Sn1 reaction,What is the significance of first step?

Explain terms Leaving Group and Electrophile.

What is Grignard reagent ?How it is prepared?

What is the natural of C-mg bond in R-mg-X?

Why does SN2mechanism give a product with inversion of configuration?

What is the role of stability of carbonium ion in deciding the Mechanism of substitution reaction.

What are b-elimination reaction?

What are primary and tertiary Alkyl Halides?

12th Class Chemistry Chapter 10 Short Questions Preparation - Set 2

Convert C2H5CI to T.E.L.

Write a note on R-Mg-X.

What is Grignard reagent ?How it is prepared?

Why the reactivity of Alkyl halides depend upon Bind Energy.

What are b-elimination reaction?

Discuss E2 mechanism.

Give general mechanism pattern of Sn2 reaction?

How will you prepare Ethyl chloride using thionylchloride.

What are primary and tertiary Alkyl Halides?

Why alkyl halides are more reactive than alkanes?

12th Class Chemistry Chapter 10 Preparation

Share your comments & questions here

Reaction of ethyl bromide with OH nucleophile is S_n2 justify?

During S_n1 reaction,What is the significance of first step?

Why does SN₂mechanism give a product with inversion of configuration?

Reaction of ethyl bromide with OH nucleophile is S_n2 justify?

During S_n1 reaction,What is the significance of first step?

Why does SN₂mechanism give a product with inversion of configuration?

Convert C₂H₅CI to T.E.L.

Give general mechanism pattern of S_n2 reaction?