Tag: haloalkanes and haloarenes

Quizzes (2) Questions (32)

Questions Related to haloalkanes and haloarenes

Multiple choice polyhalogen compounds haloalkanes and haloarenes chemistry

Which of the following is used for metal cleaning and finishing?

  1. $CHCl _{3}$
  2. $CHI _{3}$
  3. $CH _{2}Cl _{2}$
  4. $C _{6}H _{6}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Chloroform is used as solvent and as anaesthetic.
$CHI _3$ is used as antiseptic.
$CH _2Cl _2$ is used for metal cleaning and finishing.
$C _6H _6$ is used for printing and lithography, paint, rubber, dry cleaning, adhesives and coatings, detergents.

Multiple choice polyhalogen compounds haloalkanes and haloarenes chemistry

Consider the following reaction $C _2H _5I \xrightarrow[x]{\triangle} $ (Pleasant smelling liquid) X is?

  1. Sodium

  2. Dry silver oxide

  3. Ethyl chloride

  4. Dry silver powder
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Since, the product is a pleasent smelling liquid, it must be an ether. $C _2H _5I$ forms diethyl ether on reaction with dry silver oxide.

Hence $X$ is an dry silver oxide.

Multiple choice polyhalogen compounds haloalkanes and haloarenes chemistry

What is not a polyhalogen?

  1. Methyl chloride

  2. Dichloro methane

  3. Chloroform

  4. Carbon tetrachloride
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A polyhalogen compound contains more than one halogen atom in its molecule. Methyl chloride (CH3Cl) contains only one chlorine atom, making it a monohalogen compound, not a polyhalogen.

Multiple choice polyhalogen compounds haloalkanes and haloarenes chemistry

Bayer's reagent is

  1. $Br _{2}/CCl _{4}$
  2. Cold, dilute alkaline $KMnO _{4}$
  3. Acidified $KMnO _{4}$
  4. $O _{3}/Zn/H _{2}O$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bayer's reagent is defined as a cold, dilute, alkaline solution of potassium permanganate (KMnO4). It is used to test for unsaturation in organic compounds, where it turns from purple to brown.

Multiple choice polyhalogen compounds haloalkanes and haloarenes chemistry

Acidity of fluoroform (I), bromoform (II), iodoform (III) and chloroform (IV) in decreasing order is as follows:

  1. I> II> III> IV

  2. IV> III> II> I

  3. IV> I> II> III

  4. IV> I> III> II
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The acidity of haloforms depends on the stability of the conjugate base (carbanion). The stability follows the order of electronegativity of the halogen: F > Cl > Br > I. Thus, the acidity order is fluoroform > chloroform > bromoform > iodoform (IV > I > II > III).

Multiple choice polyhalogen compounds haloalkanes and haloarenes chemistry

Which of the following is used in paint removing ?

  1. $CHCl _{3}$
  2. $CH _{2}Cl _{2}$
  3. $CCl _{4}$
  4. $CH _{3}Cl$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$CHCl _3$ is used as solvent and as an anaesthetic.

$CCl _4$ is used as a fire extinguisher.
$CH _2Cl _2$ is used as paint removing.
$CH _3Cl$ is used as a refrigerant.

Hence, the correct option is B.

Multiple choice polyhalogen compounds haloalkanes and haloarenes chemistry

Carbon tetrachloride is inflammable. 

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Carbon tetrachloride (CCl4) is non-flammable and has historically been used as a fire extinguishing agent. Therefore, the statement that it is inflammable is false.

Multiple choice polyhalogen compounds haloalkanes and haloarenes chemistry

Chocolates and fatty foods containing butter or oil sometimes leave stains on clothes that are difficult to remove. They can be removed by:

  1. a solution of salt in water

  2. tetrachloroethylene

  3. water

  4. alcohol
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Chocolates and food strains can be removed by tetrachloroethylene. It is a colourless liquid widely used for cleaning of fabrics and therefore called 'Dry-Cleaning fluid'.

Multiple choice polyhalogen compounds haloalkanes and haloarenes chemistry

Dehydrohalogenation of alkyl halides is a common preparation method of:

  1. alkenes

  2. alkanes

  3. haloalkenes

  4. both A and B
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Dehydrohalogenation is an organic reaction in which alkyl halide when boiled with alcoholic alkali gives corresponding alkene. It is known as elimination reaction.