Halogen Derivative

Question 1

Alkyl halides though polar are immiscible with water?

Answer 1

1) In alkyl halide, the halogen atom is more electronegative than the carbon atom, the C-X bond is polar.
2) Though alkyl halide is polar, it is insoluble in water because alkyl halide is not able to form hydrogen bonds with water. Attraction between alkyl halide molecule is stronger than attraction between alkyl halide and water.

Question 2

Define monochromatic light.

Answer 2

It consists of rays of single wavelength vibrating in different planes perpendicular to the direction of propagation of the light.

Question 3

Define plane polarized light.

Answer 3

A light having oscillations only in one plane perpendicular to the direction of propagation is called as plane polarized light.

Question 4

Define Enantiomers

Answer 4

The optical isomers which are non super-imposable mirror image of each other are called enantiomers.

Question 5

Racemic mixture or racemate

Answer 5

A mixture containing equimolar quantities of dextro (d) and laevo (l) optical isomer which is optically inactive due to molecules of one enantiomer is cancelled by equal and opposite optical rotation due to molecules of the other racemic is called racemic mixture.

Question 6

Reactions involving Grignard reagent must be carried out in anhydrous condition.

Answer 6

(1) Grignard reagent (R. Mg X) is an organometallic compound. The carbon-magnesium bond is highly polar and magnesium halogen bond is in ionic in nature. Grignard reagent is highly reactive.
(2) The reactions of Grignard reagent are carried out in dry conditions because traces of moisture may spoil the reaction and Grignard reagent reacts with water to produce alkane. Hence, reactions involving Grignard reagent.

must be carried out under anhydrous condition

Question 7

Alkyl halides are generally not prepared by free radical halogenation of alkane.

Answer 7

(1) Free radical halogenation of alkane gives a mixture of all different possible Monohaloalkanes as well as polyhalogen alkanes.
(2) In this method, by changing the quantity of halogen the product can be made to predominate over the other
products.
Hence, alkyl halides are generally not prepared by free radical halogenation of alkane.