Which of the following is a true solution?

Options

A. copper sulphate solution
B. mudddy water
C. cement
D. milk

Explanation

To determine which of the given options is a true solution, we need to understand the characteristics of a true solution. A true solution is defined by the following criteria:

1. **Particle Size**: The particles in a true solution are typically less than 1 nanometer in size.
2. **Visibility**: The particles are not visible to the naked eye, meaning they do not scatter light (this is known as the Tyndall effect).
3. **Homogeneity**: A true solution is homogeneous, meaning it has a uniform composition throughout.

Now, let's analyze the options provided in the question step by step:

### Step 1: Understanding True Solutions
- True solutions have particles that are less than 1 nanometer in size.
- They do not scatter light and are therefore invisible.

### Step 2: Evaluating the Options
1. **Milk**:
- Milk contains fat globules and proteins that are larger than 1 nanometer, making it a colloid, not a true solution.

2. **Cement**:
- Cement particles are visible and larger than 1 nanometer, categorizing it as a suspension, not a true solution.

3. **Muddy Water**:
- Muddy water contains larger particles that settle out, making it a suspension as well.

4. **Copper Sulphate Solution**:
- Copper sulphate dissolved in water results in a solution where the particle size is less than 1 nanometer, and the solution is clear and homogeneous. Therefore, it qualifies as a true solution.

### Conclusion:
Among the options evaluated, **Copper Sulphate Solution** is the only true solution.

### Final Answer:
The true solution is **Copper Sulphate Solution**.

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