Which of the following solutions will exhibit the highest boiling point?

0.01 M Na₂SO₄ (aq)

To determine which solution has the highest boiling point, we need to calculate the value of \(i × m\) for each solution. The formula for boiling point elevation is given by:

\(\Delta T = i \cdot K_b \cdot m \)

where \( i \) is the van't Hoff factor, \( K_b \) is the molal boiling point elevation constant, and \( m \) is the molality of the solution.

Let's calculate the values of \( i \times m \) for each solution:

1. \(Na_2SO_4\):
The van't Hoff factor for \(Na_2SO_4\) is 3, as it dissociates into \(2 Na^+\) ions and \(1 SO_4^{2-}\) ion.
\( i \times m = 3 \times 0.01 \, \text{M} = 0.03 \)

2. \(KNO_3\):
The van't Hoff factor for \(KNO_3\) is 2, as it dissociates into \(1 K^+\) ion and \(1 NO_3^-\) ion.
\( i \times m = 2 \times 0.01 \, \text{M} = 0.02 \)

3. \(Urea\):
Urea does not dissociate into ions and remains as individual molecules in solution.
\(i \times m = 1 \times 0.015 \, \text{M} = 0.015 \)

4. \(Glucose\):
Similarly, glucose does not dissociate into ions and remains as individual molecules in solution.
\(i \times m = 1 \times 0.015 \, \text{M} = 0.015 \)

Comparing the values of \( i \times m \), we can see that \(Na_2SO_4\) has the highest value of 0.03. This indicates that the \(Na_2SO_4\) solution has the highest concentration of solute particles and, consequently, the highest boiling point elevation among the given solutions.

Therefore, \(Na_2SO_4\) will have the highest boiling point among the options provided.