Select correct statement :

Options

A. The fundamental cause of all colligative properties is the higher entropy of the solution relative to that of the pure solvent.
B. The freezing point of hydrofluoride solution is larger than that of equimolal hydrogen chloride solution
C. `1M` glucose solution and `0.5M NaCl` solution are isotonic at a given temperature
D. All are coorect statements

Explanation

To solve the question regarding the correct statements about colligative properties and their implications, we will analyze each statement step by step.

### Step-by-Step Solution:

1. **Understanding Colligative Properties**:
- Colligative properties depend on the number of solute particles in a solution, not on the identity of the solute. This includes properties like boiling point elevation, freezing point depression, vapor pressure lowering, and osmotic pressure.

**Hint**: Recall that colligative properties are influenced by the number of solute particles rather than their nature.

2. **Analyzing the First Statement**:
- The first statement claims that the fundamental cause of colligative properties is the higher entropy of the solution relative to the pure solvent.
- When a solute is dissolved in a solvent, new interactions are formed, increasing the randomness (entropy) of the system. Thus, this statement is correct.

**Hint**: Consider how dissolving a solute affects the arrangement and movement of solvent molecules.

3. **Analyzing the Second Statement**:
- The second statement compares the freezing points of hydrogen fluoride (HF) and hydrogen chloride (HCl) solutions.
- HF can form hydrogen bonds and tends to associate, leading to a lower effective number of particles (Van't Hoff factor, I < 1). In contrast, HCl dissociates completely into ions (I = 2).
- Given the same molarity, the freezing point depression will be less for HF than for HCl, meaning HF has a higher freezing point.

**Hint**: Remember that association decreases the number of particles in solution, affecting colligative properties.

4. **Analyzing the Third Statement**:
- The third statement discusses isotonic solutions, stating that a 1 molar glucose solution and a 0.5 molar NaCl solution are isotonic.
- For glucose (non-electrolyte), I = 1. For NaCl (strong electrolyte), I = 2 due to complete dissociation (Na⁺ and Cl⁻).
- The osmotic pressure for glucose is \( \pi = 1 \times 1 \times R \times T \) and for NaCl is \( \pi = 2 \times 0.5 \times R \times T \), which simplifies to \( \pi = 1 \times R \times T \). Thus, both have the same osmotic pressure, confirming they are isotonic.

**Hint**: Use the formula for osmotic pressure and consider how the dissociation of solutes affects the number of particles.

5. **Conclusion**:
- All three statements are correct based on the analysis above. Therefore, the correct option is **D** (all statements are correct).

### Final Answer:
**Option D: All statements are correct.**