Assertion–Reason (Deliquescence vs Hydrophobicity): Assertion (A): Common salt readily adsorbs moisture from the atmosphere. Reason (R): Salts are hydrophobic.

Introduction / Context:This item distinguishes between hygroscopic/deliquescent behavior and hydrophobicity. It checks whether the stated reason matches the surface-chemistry phenomenon described in the assertion.

Given Data / Assumptions:

• A: “Common salt” (typically NaCl; mixtures may include MgCl2, CaCl2, etc.) tends to pick up moisture in humid air.
• R: “Salts are hydrophobic.”
• Definitions: Hygroscopic substances attract water molecules; deliquescent substances absorb so much water that they dissolve. Hydrophobic substances repel water.

Concept / Approach:Many ionic salts are hygroscopic or deliquescent, especially chlorides like CaCl2 and MgCl2. Table salt can cake in humid conditions due to impurities or accompanying anti-caking agents; the moisture affinity is hydrophilic, not hydrophobic.

Step-by-Step Solution:1) A is substantially true in everyday observation: salt tends to clump by absorbing atmospheric moisture.2) R claims salts are hydrophobic. This is false: ionic solids are generally hydrophilic; some are strongly hygroscopic/deliquescent.3) Therefore the correct relationship is: A true, R false.

Verification / Alternative check:Common desiccants include CaCl2 and silica gel; the former is a salt that actively absorbs moisture, confirming hydrophilicity.

Why Other Options Are Wrong:(a)/(b) require R to be true; (d) inverts truth values; “None” is unnecessary.

Common Pitfalls:Confusing “oily/hydrophobic” behavior with ionic solids; assuming NaCl itself is strongly deliquescent (it is mildly hygroscopic, but table salt caking often involves other salts/impurities).

Final Answer:(A) is true, but (R) is false.