Give reasons for the following observations :
Why `SF_(4)` undergoes hydrolysis but not `SF_(6)`?
Or `SF_(6)` is inert towards hydroysis.
`SF_(6)` is much less reactive than `SF_(4)`.
Or (i) `SF_(4)` is easily hydrolysed whereas `SF_(6)` is not easily hydrolysed.
(ii) Sulpher exhibits greater tendency for calenation than selenium.
(iii) Sulpher has a higher tendency for catenation than oxygen.

Explanation

To answer the question regarding the observations related to the hydrolysis of SF₄ and SF₆, as well as the catenation tendencies of sulfur, selenium, and oxygen, we can break down the reasoning into clear steps.

### Step-by-Step Solution

1. **Hydrolysis of SF₄ vs. SF₆**:
- **Observation**: SF₄ undergoes hydrolysis easily, while SF₆ does not.
- **Reason**: The molecular geometry and steric hindrance play a crucial role. SF₄ has a seesaw shape due to sp³d hybridization, which allows space for water molecules to approach and react with the sulfur atom. In contrast, SF₆ has an octahedral shape with sp³d² hybridization, where the arrangement of fluorine atoms creates significant steric hindrance, preventing water molecules from effectively attacking the sulfur atom. Thus, SF₆ remains inert towards hydrolysis.

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