Fill in the blanks by choosing the appropriate word/words from those given in the brackets :
(more than, primary, cathode, Lucas reagent, two, four, less than, Grignard's -reagent, tertiary, anode, zero, equal to, three)
The elevation of boiling point of 0.5 M `K_(2)SO_(4)` solution is _______ that of 0.5 M urea solution. The elevation of boiling point of 0.5 M KCl solution is ________ that of 0.5 M `K_(2)SO_(4)` solution.

Explanation

To solve the problem, we need to understand the concept of colligative properties, specifically the elevation of boiling point, which depends on the number of particles (ions) in solution.

### Step-by-Step Solution:

1. **Identify the nature of the solutes:**
- Urea is a non-electrolyte and does not dissociate in solution. Therefore, the van 't Hoff factor (i) for urea is 1.
- `K2SO4` is an electrolyte that dissociates into 3 ions: 2 potassium ions (K⁺) and 1 sulfate ion (SO₄²⁻). Thus, the van 't Hoff factor (i) for `K2SO4` is 3.
- `KCl` is also an electrolyte that dissociates into 2 ions: 1 potassium ion (K⁺) and 1 chloride ion (Cl⁻). Therefore, the van 't Hoff factor (i) for `KCl` is 2.
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