An emulsion is a mixture of more than one liquid. It is formed by the agitation of liquids, given that it has no mutual miscibility. It consists of a dispersed phase and a dispersion medium and can be classified into two classes.
Oil in water has water as a dispersed phase and oil as the dispersion medium. In contrast, water in oil has oil as a dispersed phase and water as the dispersion medium.
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Definition: An emulsion is a mixture of more than one liquid that is generally immiscible due to liquid-liquid phase separation. It consists of two phases, i.e. dispersed phase and the dispersion medium. |
Emulsion Chemistry Questions with Solutions
Q1. Which of the following is/are examples of emulsion?
(a) Milk
(b) Butter
(c) Mayonnaise
(d) All of the above
Answer: (d) All of the above
Q2. Mayonnaise is an example of ________ emulsion.
(a) Oil in water
(b) Water in oil
(c) Natural
(d) None of the above
Answer: (a) Oil in water emulsion.
Q3. Milk is an example of ________ emulsion.
(a) Oil in water
(b) Water in oil
(c) Natural
(d) None of the above
Answer: (a) Oil in water emulsion.
Q4. The colloidal system in which the disperse phase and dispersion medium are both liquids are known as ________.
(a) Suspension
(b) Emulsion
(c) Both (a) and (b)
(d) None of the above
Answer: (b) Emulsion
Q5. Which of the following is/are examples of emulsifiers?
(a) Soap
(b) Oil
(c) Both (a) and (b)
(d) None of the above
Answer: (a) Soap
Q6. What is an emulsion?
Answer: An emulsion is a mixture of more than one liquid that is generally immiscible due to liquid-liquid phase separation. It consists of two phases, i.e. dispersed phase and the dispersion medium.
Q7. What is an emulsifier?
Answer: An emulsifier is a substance that increases the emulsion’s kinetic energy, thereby stabilising it.
Q8. What are the types of emulsions?
Answer: An emulsion is an immiscible mixture of two or more liquids. We can classify it into two types.
1. Oil in Water emulsion
2. Water in Oil emulsion
Q9. How do emulsifier agents stabilise the emulsion?
Answer: An emulsifier increases the kinetic energy and decreases the interfacial tension between the liquids, forming an emulsion, thereby stabilising it.
Q10. Give some examples of emulsions.
Answer: Paint, egg yolk, butter, mayonnaise, and cream are some examples of emulsions.
Q11. Name any three techniques used to separate emulsion.
Answer: The three techniques used to separate emulsions are mentioned below.
1. Centrifugation
2. Freezing
3. Heating
Q12. What are the properties of emulsion?
Answer: Emulsion is a mixture of liquids typically immiscible in water due to liquid-liquid phase separation. A few properties of emulsion are mentioned below.
- It comprises the dispersed phase and the dispersion medium.
- An interface separates the dispersed phase and the dispersion medium.
- It has a cloud peek.
- It demonstrates Tyndal Effect.
- The particle size distribution of the dispersed phase is not uniform.
- They are unstable.
- We can separate the dispersed phase from the dispersion medium by keeping it undisturbed for a while.
Q13. What is water in oil emulsion?
Answer: Emulsion having water as a dispersed phase and oil as the dispersion medium is known as water in oil emulsion. Water acts as an internal phase, whereas oil acts as an external phase in this emulsion.
Example: Butter, cold cream.
Q14. What is oil in water emulsion?
Answer: Emulsion having oil as a dispersed phase and water as the dispersion medium is known as oil in water emulsion. The oil acts as an internal phase, whereas water acts as an external phase in this emulsion.
Example: Milk, egg yolk.
Q15. Differentiate between emulsion and suspension.
Answer:
|
S. No. |
Emulsion |
Suspension |
|---|---|---|
|
1. |
An emulsion is a heterogeneous mixture of two immiscible liquids. It is a type of colloid, and dispersed particles do not settle on standing. |
Suspension is a heterogeneous mixture where the dispersed particles are large and settle on. standing |
|
2. |
The size of the particle is between 1 to 1000 nm. |
The size of particles is more than 1000 nm. |
|
3. |
It can not be separated by filtration. |
It can be separated by filtration. |
|
4. |
Example: Butter, milk, egg yolk, cold cream. |
Example: Sand water, Flour water. |
Practise Questions on Emulsion
Q1. Explain the mechanism of emulsion.
Q2. What are the applications of emulsion?
Q3. What is a complex emulsion?
Q4. What is Emulsification?
Q5. What is flocculation?
Click the PDF to check the answers for Practice Questions. Download PDF
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