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Q.
The solubility order for alkali metal fluoride in water is :
NTA AbhyasNTA Abhyas 2022
Solution:
lattice enthalpy $ \propto \frac{1}{S o l u b i l i t y}$
Since the lattice enthalpy follow the order
$\text{LiF} \, \text{>} \, \text{NaF} \, \text{>} \, \text{KF} \, \text{>} \, \text{RbF}$
Hence, the correct order of solubility is
$LiF < NaF < KF < RbF$