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Multiple choice acyl chlorides carboxylic acids and their derivatives functional derivatives of carboxylic acids carbonyl compounds chemistry

Identify the main functional derivative of carboxylic acid.

  1. Ester

  2. Alkane

  3. Alcohol

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ester is the main functional derivative of carboxylic acid. Ester has general formula $\displaystyle  R - \underset {   \underset {\displaystyle O}{||}  }{C} - OR'  $. Carboxylic acid has general formula $\displaystyle  R - \underset {   \underset {\displaystyle O}{||}  }{C} - OH  $. An example of ester is ethyl acetate $\displaystyle  CH _3 - \underset {   \underset {\displaystyle O}{||}  }{C} - O-CH _2-CH _3  $. An example of carboxylic acid is acetic acid $\displaystyle  CH _3 - \underset {   \underset {\displaystyle O}{||}  }{C} - OH  $

Multiple choice acyl chlorides carboxylic acids and their derivatives functional derivatives of carboxylic acids carbonyl compounds chemistry

Acyl halide and acid halide are same groups.

  1. True

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

The given statement is True.
Acyl halide and acid halide are same groups. They represent the function group
  $\displaystyle R- \underset {\displaystyle  \underset {\displaystyle \text {O }}{||} }{C}-X$  where X is halogen atom (F, Cl, Br or I). They are derived from carboxylic acids (  $\displaystyle R- \underset {\displaystyle  \underset {\displaystyle \text {O }}{||} }{C}-OH$ ) by replacing a hydroxyl group (-OH) with a halide group.
An example is acetyl chloride  $\displaystyle CH _3- \underset {\displaystyle  \underset {\displaystyle \text {O }}{||} }{C}-Cl$
Another example is benzoyl chloride $\displaystyle Ph- \underset {\displaystyle  \underset {\displaystyle \text {O }}{||} }{C}-Cl$

Multiple choice chemistry separation of substances mixtures: examples and properties types of solutions all about mixtures

A salt is made by adding an excess of an insoluble metal oxide to an acid. How is the excess metal oxide removed from the mixture?

  1. chromatography

  2. crystallisation

  3. distillation

  4. filtration
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
$\text{Filtration is defined as the process of separating suspended solid matter from a liquid.}$$\text{ So it can be used to remove metal oxide from the mixture.}$
Multiple choice chemistry separation of substances mixtures: examples and properties types of solutions all about mixtures

State True or False.
A mixture can not be represented by a chemical formula.

  1. True

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

In chemistry, a mixture is a material system made up of two or more different substances which are mixed but are not combined chemically. A mixture refers to the physical combination of two or more substances on which the identities are retained and are mixed in the form of solutions, suspensions, and colloids.

Multiple choice chemistry separation of substances mixtures: examples and properties types of solutions all about mixtures

Example of  a 'solid in liquid' mixture is :

  1. oil in water

  2. muddy water

  3. smoke

  4. all of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 Phases of matter   Name of mixture  Examples
 Liquid - liquid  Emulsion  Oil in water
 Solid - liquid  Suspension  Muddy water
 Gas - liquid  Aerosol  Fizzy drinks
 gas - solid  Smoke  Smog

A mixture is a combination of two or more substances, where these substances are not bonded (or joined) to each other and no chemical reaction occurs between the substances.