Q23 / 170 · Manipal (MET) 2020 · Chemistry
Correct order for solubility of alkaline earth metals in water is
- Correct answerA$\mathrm{MgF}_2\gt\mathrm{CaF}_2\gt\mathrm{SrF}_2\gt\mathrm{BaF}_2$
- B$\mathrm{MgF}_2 \lt \mathrm{CaF}_2 \lt \mathrm{SrF}_2 \lt \mathrm{BaF}_2$
- C$\mathrm{MgF}_2\gt\mathrm{CaF}_2 \lt \mathrm{SrF}_2 \lt \mathrm{BaF}_2$
- D$\mathrm{BaF}_2\gt\mathrm{MgF}_2\gt\mathrm{SrF}_2\gt\mathrm{CaF}_2$
Solution
Order of solubility of fluorides of alkaline earth metals in water is
Halides of alkaline earth metals (except Be) are ionic solids and are therefore are water soluble and their solubility in water decreases from Mg to Ba due to the decrease in the hydration energy.
However, fluorides of alkanline earth metals excepts $\mathrm{BeF}_2$ are almost insoluble in water.
Hence, the correct answer is option: 'A'.