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प्रश्न
Explain micelle formation in a soap solution.
Explain the formation of a micelle in soap solution.
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उत्तर
- A soap molecule has a long hydrophobic hydrocarbon chain called a tail, which is attached to the hydrophilic ionic carboxylate group, called the head.
- In water, the soap molecules arrange themselves to form spherical particles that are called micelles.
- In each micelle, the hydrophobic tails of soap molecules point to the center, and the hydrophilic heads lie on the surface of the sphere.
- As a result of this, soap dispersion in water is stable.
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संबंधित प्रश्न
Choose the correct option.
The size of colloidal particles lies between ______.
Identify the dispersed phase and dispersion medium in the following colloidal dispersions.
- milk
- blood
- printing ink
- fog
Write Hardy-Sulze rules.
Write a note on the Tyndall effect.
Explain Bredig’s arc method.
Explain the term emulsion and types of emulsions.
Draw labelled diagram of Soap micelle.
Which of the following is multimolecular colloid?
Identify the CORRECT statements from the following.
i. The colour of colloidal dispersion depends on size of colloidal particles.
ii. Tyndall effect is used to distinguish between colloidal dispersion and true solution.
iii. Eosin and congo red are examples of negatively charged sols.
In coagulation of positively charged ferric hydroxide sol, the most and least effective ions are ____________ and ____________ respectively.
Which of the following statements is CORRECT?
Which of the following is an example of liquid-liquid system?
Maximum coagulation power is in ____________.
Which of the following is NOT true for lyophilic colloids?
Mixing of two oppositely charged sols leads to ____________.
Tyndall effect is observed due to ____________.
Tyndall effect is useful ______.
The movement of colloidal particles towards respective electrode under electric field is called ______.
Some colloids are stable by their nature, i.e., gels, alloys, and solid foams. Gelatin and jellies are two common examples of a gel. The solid and liquid phases in a gel are interdispersed with both phases being continuous. In most systems, the major factor influencing the stability is the charge on the colloidal particles. If a particular ion is preferentially adsorbed on the surface of the particles, the particles in suspension will repel each other, thereby preventing the formation of aggregates that are larger than colloidal dimensions. The ion can be either positive or negative depending on the particular colloidal system, i.e., air bubbles accumulate negative ions, sulphur particles have a net negative charge in a sulphur sol, and the particles in a metal hydroxide sol are positively charged. Accumulation of charge on a surface is not an unusual phenomenon-dust is attracted to furniture surfaces by electrostatic forces. When salts are added to lyophobic colloidal systems the colloidal particles begin to form larger aggregates and a sediment forms as they settle. This phenomenon is called flocculation, and the suspension can be referred to as flocculated, or colloidally unstable. If the salt is removed, the suspension can usually be restored to its original state; this process is called deflocculation or peptization. The original and restored colloidal systems are called deflocculated, peptized, or stable sols.
Why does a small amount of salt have such a dramatic effect on the stability of a lyophobic colloidal system? The answer lies in an understanding of the attractive and repulsive forces that exist between colloidal particles. Van der Waals forces are responsible for the attractions, while the repulsive forces are due to the surface charge on the particles. In a stable colloid, the repulsive forces are of greater magnitude than the attractive forces. The magnitude of the electrical repulsion is diminished by addition of ionized salt, which allows the dispersed particles to aggregate and flocculate. River deltas provide an example of this behaviour. A delta is formed at the mouth of a river because the colloidal clay particles are flocculated when the freshwater mixes with the salt water of the ocean.
Gelatin is a _________ colloidal system.
Which of the following process is responsible for the formation of delta at a place where rivers meet the sea?
On the basis of Hardy-Schulze rule explain why the coagulating power of phosphate is higher than chloride.
Why is \[\ce{Fe(OH)3}\] colloid positively charged, when prepared by adding \[\ce{FeCl3}\] to hot water?
Colloids can
The coagulation of 200 ML of position sol took place when 0.73 HCL was added to its without changing the volume much. The flocculation value of HCL for the colloid is.
In which of the following, the Tyndall effect is not observed?
Identify the colloidal molecule containing hydrophilic head and hydrophobic tail within it.
Identify the correct decreasing order of precipitation power of flocculating ion added, from following.
