Which has highest boiling under 1 atm. pressure?

Options

A. 0.1 M NaCl
B. 0.1 M Surcrose
C. 0.1 M `BaCl_2`
D. 0.1 M Glucose

Explanation

To determine which solution has the highest boiling point under 1 atm pressure, we need to consider the colligative properties of solutions, specifically boiling point elevation. The boiling point elevation can be calculated using the formula:

\[ \Delta T_b = i \cdot K_b \cdot m \]

Where:
- \(\Delta T_b\) = elevation in boiling point
- \(i\) = van 't Hoff factor (number of particles the solute dissociates into)
- \(K_b\) = ebullioscopic constant (a property of the solvent)
- \(m\) = molality of the solution

Since all the solutions given in the question are 0.1 molar, we can focus on the van 't Hoff factor \(i\) to determine which solution will have the highest boiling point.

### Step 1: Identify the dissociation of each solute
1. **NaCl (sodium chloride)**: Dissociates into 2 ions (Na\(^+\) and Cl\(^-\)), so \(i = 2\).
2. **Sucrose**: Does not dissociate, so \(i = 1\).
3. **BSL2 (assumed to be a salt like BaCl\(_2\))**: Dissociates into 3 ions (Ba\(^{2+}\) and 2 Cl\(^-\)), so \(i = 3\).
4. **Glucose**: Does not dissociate, so \(i = 1\).

### Step 2: Compare the van 't Hoff factors
- NaCl: \(i = 2\)
- Sucrose: \(i = 1\)
- BSL2: \(i = 3\)
- Glucose: \(i = 1\)

### Step 3: Determine which has the highest boiling point
Since the boiling point elevation \(\Delta T_b\) is directly proportional to \(i\), the solution with the highest \(i\) will have the highest boiling point.

From our calculations:
- BSL2 has the highest \(i\) value of 3.

### Conclusion
Thus, the solution with the highest boiling point under 1 atm pressure is the one containing BSL2.

**Final Answer**: BSL2 (option number 3).

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