Understanding Solubility in Water
When discussing solubility, it's important to know how different materials interact with water. Let's look at the options provided:
1. Sand
- Sand is made up of tiny particles of rock and minerals.
- It does not dissolve in water; instead, it settles at the bottom when mixed.
2. Chalk
- Chalk is primarily composed of calcium carbonate.
- When added to water, it does not dissolve significantly; it may break down into small particles but remains mostly intact.
3. Sugar
- Sugar is a carbohydrate made up of carbon, hydrogen, and oxygen.
- It is highly soluble in water, meaning it dissolves completely when mixed, forming a sweet solution.
4. Clay
- Clay consists of fine particles and has some water absorption properties.
- However, it does not dissolve in water like sugar; instead, it can become muddy or form a suspension.
Conclusion
The correct answer is option 'C' (Sugar) because it readily dissolves in water, creating a homogeneous solution. The other materials (sand, chalk, and clay) do not dissolve in water in the same way, making sugar the standout choice for solubility.
Understanding these differences in solubility helps in various applications, from cooking to scientific experiments.

Sugar dissolves in water, forming a solution, while sand, chalk, and clay do not dissolve in water.