A solution of urea in water has a boiling point of `100*18^@C`. Calculate the freezing point of the solution.(K for water is `1*86 " K kg " mol^(-1) and K_b " for water is " 0*512 " K kg " mol^(-l)` ).

Explanation

To solve the problem step-by-step, we will follow the concepts of boiling point elevation and freezing point depression.

### Step 1: Identify the given data
- Boiling point of the solution (T_b) = 100.18 °C
- Boiling point of pure water (T_b, solvent) = 100 °C
- K_b (boiling point elevation constant for water) = 0.512 K kg mol⁻¹
- K_f (freezing point depression constant for water) = 1.86 K kg mol⁻¹

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