S Block Elements

Analysis of Statement-I: Both $\mathrm{BeSO}_4$ and $\mathrm{MgSO}_4$ are readily soluble in water.The solubility of sulfates of alkaline earth metals generally decreases down the group.$\mathrm{BeSO}_4$ (Beryllium sulfate) is readily soluble in water. This is due to the very small size of the $\mathrm{Be}^{2+}$ ion, which leads to very high hydration energy. This high hydration energy more than compensates for the relatively high lattice energy, making it highly soluble.$\mathrm{MgSO}_4$ (Magnesium sulfate, commonly known as Epsom salt) is also readily soluble in water. Similar to beryllium, the $\mathrm{Mg}^{2+}$ ion is relatively small, leading to significant hydration energy.In contrast, $\mathrm{CaSO}_4$ (Calcium sulfate) is sparingly soluble, and $\mathrm{SrSO}_4$ (Strontium sulfate) and $\mathrm{BaSO}_4$ (Barium sulfate) are practically insoluble.Therefore, Statement - I is correct.Analysis of Statement - II: Among the nitrates of alkaline earth metals, only $\mathrm{Be}(\mathrm{NO}_3)_2$ on strong heating gives its oxide, $\mathrm{NO}_2$ and $\mathrm{O}_2$.Alkaline earth metal nitrates decompose on strong heating to give the metal oxide, nitrogen dioxide ( $\mathrm{NO}_2$ ), and oxygen $(\mathrm{O}_2)$. The general reaction is:$2 \mathrm{M}(\mathrm{NO}_3)_2(s) \xrightarrow{\; \text{heat} \;} 2 \mathrm{MO}(s) + 4 \mathrm{NO}_2(g) + \mathrm{O}_2(g)$This decomposition pattern is observed for all alkaline earth metal nitrates.$\; \mathrm{Be}(\mathrm{NO}_3)_2 \xrightarrow{\; \text{heat} \;} \mathrm{BeO} + 2 \mathrm{NO}_2 + \frac{1}{2} \mathrm{O}_2$$\; \mathrm{Mg}(\mathrm{NO}_3)_2 \xrightarrow{\; \text{heat} \;} \mathrm{MgO} + 2 \mathrm{NO}_2 + \frac{1}{2} \mathrm{O}_2$$\; \mathrm{Ca}(\mathrm{NO}_3)_2 \xrightarrow{\; \text{heat} \;} \mathrm{CaO} + 2 \mathrm{NO}_2 + \frac{1}{2} \mathrm{O}_2$And similarly for $\mathrm{Sr}(\mathrm{NO}_3)_2$ and $\mathrm{Ba}(\mathrm{NO}_3)_2$.The thermal stability of these nitrates generally increases down the group $(\mathrm{Be}(\mathrm{NO}_3)_2.$ is the least stable, and $\mathrm{Ba}(\mathrm{NO}_3)_2$ is the most stable), meaning they decompose at different temperatures, but the decomposition products are the same for all of them.The statement claims that "only $\mathrm{Be}(\mathrm{NO}_3)_2$ " decomposes in this manner, which is incorrect as all alkaline earth metal nitrates follow this decomposition pathway.Therefore, Statement - II is not correct.Conclusion:Statement - I is correct.Statement - II is not correct.This matches option B.