How would you explain the following observation ? BeO is almost insoluble but BeSO_4 is soluble in water.

How would you explain the following observation ? BeO is almost insolu

1.	How would you explain the following observation ? BeO is almost insoluble but BeSO_4 is soluble in water.
Answer» Solution :(i) BeO is almost insoluble in water because `Be^(2+)` is a small cation with high polarising power and `O^(2)` is small anion. `:.` The lattice ENERGY very high when BeO is dissolved in water, the hydration energy of its ions is not SUFFICIENT to overcome high lattice energy. (II) On the other hand `Be^(2+)` is a small cation and `SO_4^(2-)` is a large anion. HENCE `Be^(2+)` can easily polarize `SO_4^(2-)` ions, making `BeSO_4` unstable the lattice energyof `BeSO_4` is not very high and so it is soluble in water.