The hydroxides and carbonates of sodium and potassium are easily soluble in water,while the corresponding salts of magnesium and calcium are sparingly soluble in water. Explain.

(N/A) The atomic size of $Na$ and $K$ is larger than that of $Mg$ and $Ca$.
Due to the smaller size and higher charge density of $Mg^{2+}$ and $Ca^{2+}$ ions,the lattice energies of their carbonates and hydroxides are significantly higher than those of $Na^+$ and $K^+$ salts.
Since the hydration energy of $Mg^{2+}$ and $Ca^{2+}$ is not sufficient to overcome their high lattice energy,their carbonates and hydroxides are only sparingly soluble in water.
In contrast,the lower lattice energy of $Na$ and $K$ salts allows them to dissolve readily in water.