Chemistry · Science General

Separation Techniques

813 Questions

Separation techniques involve physical methods to isolate mixtures, including distillation, filtration, and crystallization. Competitive exams frequently test these foundational concepts. Review the exact processes to enhance problem solving speed.

Distillation and evaporationCrystallization processFiltration methodsSeparating dissolved solidsChromatography and mass techniques

Separation Techniques Questions

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

The process of crystallization is used to obtain pure solids because:

  1. iIt is better than evaporation

  2. impurities are filtered completely

  3. ultra pure crystals are formed

  4. decomposition does not take place
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Since crystallization generally produces salts which are crystalline in state or $100$ percent purity in state.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

What is the method to separate two compounds with different solubilities in a solvent? 

  1. Sublimation

  2. Crystallization

  3. Chromatography

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

Two compounds which have different solubilities in a solvent S can be separated from each other by Fractional Crystallisation. The process involves a series of repeated-crystallisations. The mixture of the two compounds in the solvent S is heated so as to make it saturated. When the hot solution is allowed to cool, the less soluble substance crsytallises out first while the more soluble substance remains in the solution. The crystals of first compound are separated from the mother liquor and the mother liquor is again concentrated and allowed to cool when the crystals of the 2nd compound are obtained.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

Separation of a mixture into its components, whose boiling points are different, is called :

  1. fractional distillation

  2. destructive distillation

  3. displacement

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

Separation of a mixture into its components whose boiling points are different is called Fractional distillation.
This method is used for separating a mixture of two or more volatile liquids both having close boiling points. The boiling points of two components differ by 10-15 K. For example, acetone and methanol with boiling points 329 K and 338 K can be separated  by this method. This method is used for distillation of petroleum, coal tar and crude alcohol.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

Which of the following is/are true?

  1. When carbolic oil is cooled, naphthalene crystallizes out

  2. Naphthalene is purified by sublimation

  3. Naphthalene is used for manufacture of dyes, drugs, explosives etc

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

All of the following statements are true.
When carbolic oil is cooled, naphthalene crystallizes out.
Naphthalene is purified by sublimation.
Naphthalene is used for manufacture of dyes, drugs, explosives etc.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

Separation of two substances by crystallisation depends upon their differences in:

  1. densities

  2. solublity

  3. melting point

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

Separation of $2$ substances by crystallization depends upon their difference in solubility as more soluble impurity will go into the solution and less soluble component will crystallize out.

Multiple choice chemistry mix and separate different types of mixtures homogenous and heterogenous mixtures all about mixtures

Which of the following mixtures will be the most difficult to separate?

  1. Iron filings + sand

  2. Sand + water

  3. Saw dust + stones

  4. Nitrogen + hydrogen
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Nitrogen (N2) form ammonia (NH3) by a reaction with hydrogen (H2) using a metal catalyst under high temperatures and pressures. It is a chemical combination reaction. Hence the mixture of nitrogen and hydrogen is difficult to separate because a new product is formed.

Multiple choice dyes dyes and pigments chemistry in daily life applied chemistry chemistry

A colloidal solution can be purified by following the method of:

  1. dialysis

  2. peptization

  3. filtration

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

A colloidal solution can be purified by the following methods - Dialysis, Electro-dialysis and Ultrafiltration.

Hence, option A is the correct answer.

Multiple choice

which type chemical are purified through vaccume distilation.

  1. Low quality

  2. Temperature sensitive

  3. high reactive chemical

  4. less reactive chemical
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

"Temperature sensitive " all chemical which are temperature sensitive can be done through this method. for example .glycerin bioling point is 290degree but before this tempertature it decompose.

Multiple choice

What is the most common type of chromatography?

  1. Gas chromatography

  2. Liquid chromatography

  3. Thin-layer chromatography

  4. Paper chromatography
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Gas chromatography is the most common type of chromatography because it is used to separate and analyze volatile compounds.