Which from following is an example of multimolecular colloid?
Step-by-Step Solution
Step 1: What Is a Multimolecular Colloid?
First, let’s understand what a colloid is. A colloid is a mixture where tiny particles are spread out in a medium but don’t settle down—like milk or fog. There are different types of colloids, and one type is called a multimolecular colloid. This happens when many small molecules come together to form particles that are big enough to be colloidal (usually between 1 nm and 1000 nm in size). These particles are made up of aggregates of molecules. Cool, right? Now, let’s see which option fits this!
Step 2: Check Each Option
Let’s look at each substance and decide if it can form a multimolecular colloid:
Cellulose is a complex carbohydrate found in plant cell walls, made up of long chains of glucose molecules. While it’s a big molecule, it doesn’t typically form colloidal particles by aggregating small molecules in the way multimolecular colloids do. It’s more of a macromolecule on its own.
Plastics are synthetic polymers, like polyethylene, made of long chains of repeating units. They are usually solid materials and don’t form colloidal dispersions by aggregating small molecules into colloidal-sized particles. So, plastic isn’t a multimolecular colloid.
S8 refers to a molecule of sulfur, where eight sulfur atoms form a ring. This is a single molecule, not an aggregate of many small molecules forming a larger colloidal particle. Multimolecular colloids need many molecules to come together, so S8 doesn’t fit.
Starch is a carbohydrate stored in plants, made of many glucose molecules. In water, starch can break down into smaller units and form colloidal particles when these units aggregate into clusters that are the right size (1 nm to 1000 nm). This makes starch a classic example of a multimolecular colloid, especially in things like starch suspensions!
Step 3: Pick the Right One
From our list, Cellulose and Plastic are large molecules but don’t form colloids through aggregation of small molecules. The S8 molecule is a single entity, not a colloid. Starch, however, fits perfectly because its glucose units can aggregate into colloidal-sized particles in a suitable medium like water. So, Starch is our winner!
Step 4: Match with Options
The options provided are:
Since Starch is the substance that forms a multimolecular colloid, the correct answer is Option 4.
Final Answer: Option 4 (Starch) is correct.
List-I (Sol) | List-II (Method of preparation) |
---|---|
A) \( \text{As}_2\text{S}_3 \) | I) Bredig's arc method |
B) \( \text{Au} \) | II) Oxidation |
C) \( \text{S} \) | III) Hydrolysis |
D) \( \text{Fe(OH)}_3 \) | IV) Double decomposition |