Question

A colloidal system having a solid substance as a dispersed phase and a liquid as a dispersion medium is classified as (a) Solid sol (b) Emulsion (c) Sol (d) Gel

Short answer

The colloidal system is classified as (c) Sol.

Step-by-step solution

Understand the Components

Read the question carefully. The colloidal system has a solid substance as the dispersed phase and a liquid as the dispersion medium.

Recall Types of Colloidal Systems

In a colloidal system, different combinations of dispersed phase and dispersion medium have specific names. Recall the names: a solid in a liquid is commonly referred to as a sols.

Identify Given Colloidal System

We need to match the situation described in the problem to one of the available options: solid sol, emulsion, sol, or gel. Since the dispersed phase is solid and the dispersion medium is a liquid, it fits the description of a sol.

Eliminate Incorrect Options

Verify that the other options do not match the description: - Solid sol and gel both imply a solid continuous phase, which doesn't meet the criteria. - Emulsion refers to a liquid-liquid colloidal system.

Confirm the Correct Classification

The only option that correctly describes a system with a solid dispersed in a liquid is 'sol'.

Key concepts

Dispersed Phase and Dispersion Medium

In colloidal systems, the terms 'dispersed phase' and 'dispersion medium' help define the structure and characteristics of the system. The dispersed phase consists of particles dispersed throughout another substance. This substance in which the particles are distributed is known as the dispersion medium.

A helpful way to think about these concepts is to imagine making a salad dressing. Oil droplets (dispersed phase) are distributed in vinegar (dispersion medium). Depending on the components used, a wide variety of colloidal systems can emerge. The nature of the dispersed phase and dispersion medium defines the behavior and type of colloid created.

• Dispersed Phase: The substance's state that is broken up or distributed. For example, in a sol, this would be the solid particles.
• Dispersion Medium: The medium that holds or contains the dispersed phase. In a sol, this would typically be a liquid.

Understanding these components is essential for recognizing and classifying different types of colloids seen in chemistry.

Types of Colloids

Colloids are classified based on the states of matter of both their dispersed phase and their dispersion medium. The main types include sols, gels, emulsions, foams, and aerosols. Each type has distinctive properties and applications based on its composition.

Let's explore a few common types:

• Sols: A colloid with solid particles dispersed in a liquid. An example is paint, which consists of pigment particles suspended in a solvent.
• Gels: Here, a liquid is dispersed in a solid network. Common examples include gelatin desserts and jelly.
• Emulsions: Consists of liquid-liquid mixtures, like mayonnaise, which is an emulsion of oil in vinegar.

Understanding these basic types helps in recognizing practical uses and behaviors of colloids in daily life and industrial processes.

Sol Classification

Sol classification is specific to colloids where a solid is dispersed in a liquid. This state gives sols unique properties distinct from other types of colloids. Sols are versatile, occurring in natural and synthetic forms with varying properties.

Key characteristics of sols include:

• Stability: Sols tend to be quite stable, although stability varies depending on the interaction between the solid particles and the liquid medium.
• Transparency or Opacity: Many sols appear either transparent or mildly opaque, influenced by the particle size of the dispersed solid.
• Applications: Sols are widely used in industries, for example in the manufacture of inks, paints, and medicines.

By understanding sol classification, you can predict behavior and usability across different applications, making it a critical topic for students exploring chemistry and material sciences.