Question

The increase in the solubility of Sodium halides, in water at 25°C is:

• A. NaCl > NaBr > NaI
• B. NaBr > NaI > NaCl
• C. NaI > NaBr > NaCl
• D. NaCl = NaBr > NaI

Hint:

Larger ions like iodide (I-) tend to form weaker ionic bonds with sodium, making NaI more soluble in water than NaBr and NaCl.

Answer 1

The Correct Option is C

The increase in the solubility of Sodium halides, in water at 25°C is: 

• Option 1: NaCl > NaBr > NaI - This is incorrect. As the size of the halide ion increases, the solubility tends to decrease.
• Option 2: NaBr > NaI > NaCl - This is also incorrect. The solubility does not follow this trend at 25°C.
• Option 3: NaI > NaBr > NaCl - This is the correct answer. The solubility of sodium halides in water increases as the size of the halide ion increases. NaI has the highest solubility, followed by NaBr, and NaCl has the lowest solubility.
• Option 4: NaCl = NaBr > NaI - This is incorrect because NaI has a higher solubility than both NaCl and NaBr at 25°C.

Explanation:

The solubility of sodium halides in water at 25°C increases in the order of NaI > NaBr > NaCl. This is because as the ionic radius of the halide ion increases, the lattice energy of the salt decreases, allowing it to dissolve more easily in water.