Follwing are equimolal aqueous solution:
a.`1 m urea` , b.`1 m KCl` , c.`1 m MgCl_(2)` , d.`1 m Na_(3)PO_(4)`
Arrange them in increaseing
i. Boiling point , ii.Freezing point , iii. Osmotic pressure , iv.Vapour pressure

Explanation

To solve the problem of arranging the given equimolar aqueous solutions in increasing order of boiling point, freezing point, osmotic pressure, and vapor pressure, we will use the concept of colligative properties. These properties depend on the number of solute particles in a solution rather than the identity of the solute.

### Step-by-Step Solution:

1. **Identify the van 't Hoff factor (i)** for each solute:
- **Urea (1 m)**: Urea does not dissociate in solution, so \( i = 1 \).
- **KCl (1 m)**: KCl dissociates into 2 ions (K\(^+\) and Cl\(^-\)), so \( i = 2 \).
- **MgCl\(_2\) (1 m)**: MgCl\(_2\) dissociates into 3 ions (Mg\(^{2+}\) and 2 Cl\(^-\)), so \( i = 3 \).
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