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प्रश्न
Account for the following observations:
Though fluorine is more electronegative than chlorine yet BF3 is a weaker Lewis acid than BCl3
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उत्तर
Undoubtedly, fluorine has more electronegativity than chlorine, BF3 is stronger Lewis acid than BCl3 because of n – pπ back bonding in BF3, both the constituting atoms boron and fluorine are involved p-orbital in back bonding. On moving down the group, the size of halogen atoms increases, back bonding decreases and Lewis acid character also decreases.
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संबंधित प्रश्न
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AlCl3
Explain the following:
Boron does not exist as B3+ ion.
Explain the following:
Tl (NO3)3 acts as an oxidising agent.
Match the species given in Column I with the properties mentioned in Column II.
| Column I | Column II |
| (i) \[\ce{BF^{-}4}\] | (a) Oxidation state of central atom is +4 |
| (ii) AICI3 | (b) Strong oxidising agent |
| (iii) SnO | (c) Lewis acid |
| (iv) PbO2 | (d) Can be further oxidised |
| (e) Tetrahedral shape |
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PbO2 is a stronger oxidising agent than SnO2
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