The factor `(DeltaT_(f)//K_(f))` represents

Options

A. Molarity
B. Formality
C. Normality
D. Molality

Explanation

To solve the question regarding the factor \((\Delta T_f / K_f)\), we will follow these steps:

### Step 1: Understand the Terms
- \(\Delta T_f\) is the depression in freezing point.
- \(K_f\) is the molal freezing point depression constant.

### Step 2: Recall the Formula
The relationship between the depression in freezing point and molality is given by the formula:
\[ \Delta T_f = i \cdot K_f \cdot m \]
where:
- \(i\) is the van 't Hoff factor (which accounts for the number of particles the solute dissociates into),
- \(m\) is the molality of the solution.

### Step 3: Rearranging the Formula
From the formula above, we can rearrange it to express molality \(m\):
\[ m = \frac{\Delta T_f}{i \cdot K_f} \]

### Step 4: Considering the Case of Non-dissociating Solutes
For non-dissociating solutes, the van 't Hoff factor \(i\) is equal to 1. Therefore, the equation simplifies to:
\[ m = \frac{\Delta T_f}{K_f} \]

### Step 5: Conclusion
Thus, the factor \((\Delta T_f / K_f)\) represents the molality of the solution.

### Final Answer
The factor \((\Delta T_f / K_f)\) represents the **molality** of the solution.

---