Which of the following set of order is INCORRECT for their indicated properties?

Question

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The incorrect options are (C) and (D):

For (C): While AlF₃ is ionic with a very high melting point, the others are covalent molecular dimers (Al₂X₆) whose melting points depend on van der Waals forces, making the correct order: AlF₃ > AlCl₃ > AlBr₃ > AlI₃.

For (D): The water solubility of alkali metal nitrates decreases down the group (

$L i N O_{3} > N a N O_{3} > K N O_{3} > R b N O_{3}$

).

This happens because the hydration energy of the metal cations decreases much faster than the lattice energy as the cation size increases from Li⁺ to Rb⁺.

Options (A) and (B) are correct statements based on Fajan's rules and the inert pair effect, respectively.

Chemistry - CHEMICAL BONDING Question with Solution | TestHub

Options:(select one or more)

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