Question 10.20 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.
The solubility of a salt in water depends upon the lattice energy and hydration energy. ∆H{solution} = ∆H{lattice energy} + ∆H{hydration energy}
More negative is ∆H{solution}, more is the solubility of compounds. For sodium and potassium hydroxides and carbonates hydration energy is more than that of their lattice energy. Therefore, they are soluble in water. For magnesium and calcium hydroxides and carbonates lattice energy is greater than that of their hydration energy. Therefore, these are sparingly soluble in water
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The solubility of a salt in water depends upon the lattice energy and hydration energy.∆H{solution} = ∆H{lattice energy} + ∆H{hydration energy}
More negative is ∆H{solution}, more is the solubility of compounds. For sodium and potassium hydroxides and carbonates hydration energy is more than that of their lattice energy. Therefore, they are soluble in water. For magnesium and calcium hydroxides and carbonates lattice energy is greater than that of their hydration energy. Therefore, these are sparingly soluble in water