Among `MgSO_4, CaSO_4, SrSO_4 and BaSO_4`, which one is most soluble in water ?

Explanation

To determine which sulfate among \( \text{MgSO}_4, \text{CaSO}_4, \text{SrSO}_4, \text{and} \text{BaSO}_4 \) is most soluble in water, we can follow these steps:

### Step 1: Understand the Factors Affecting Solubility
The solubility of sulfates in water is influenced by two main factors: lattice enthalpy and hydration enthalpy.

### Step 2: Lattice Enthalpy
Lattice enthalpy is the energy required to separate one mole of a solid ionic compound into its gaseous ions. Generally, smaller cations have higher lattice enthalpy because they can pack more closely together, leading to stronger ionic bonds.

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