Arrange the following sulphates of alkaline earth metals in order of decreasing thermal stability: `BeSO_(4),MgSO_(4),CaSO_(4),SrSO_(4)`.

Explanation

To arrange the sulfates of alkaline earth metals (BeSO₄, MgSO₄, CaSO₄, SrSO₄) in order of decreasing thermal stability, we need to consider the thermal stability of these sulfates as we move down the group in the periodic table.

### Step-by-Step Solution:

1. **Understanding Thermal Stability**:
Thermal stability refers to the temperature at which a compound decomposes. For sulfates of alkaline earth metals, the decomposition reaction can be represented as:
\[
MSO_4 \rightarrow MO + SO_3
...