A) LiF > NaF > KF > RbF > CsF
B) CsF > RbF > KF > NaF > LiF
C) LiF > KF > NaF > CsF > RbF
D) CsF > KF > NaF > RbF > LiF
Correct Answer: B
Solution :
\[LiI>NaI>KI>RbI>CsI\] (solubility) Lattice energy \[\xrightarrow[{{r}_{+}}+{{r}_{-}}]{1}\] Since, \[{{r}_{-}}+{{r}_{+}}\], the sum will not change too much as \[{{r}_{+}}\] increases. As a result the lattice energy will not change significantly as \[{{r}_{+}}\] increases. Thus decreases in lattice energy is not as fast as decreases in hydration energy. Thus, more decrease in hydration energy results in decrease in solubility. Thus, solubility decreases as \[LiI>NaI>KI>RbI>CsI\] With a small anion as \[({{F}^{-}})\], the lattice energy decreases more rapidly along a series of salts with increasing cation size and thus, solubility increases. \[LiF<NaF<KF<RbF<CsF\]
You need to login to perform this action.
You will be redirected in
3 sec
