Statement I : Hard water does not give lather with soap .
Statement II : Calcium and magnesium salts present in hard water form precipitate with soap .

Options

A. Both the statements individually true and Statement II is the correct explanation of Statement I.
B. Both the statements are individually true but Statement II is not correct explanation of Statement I.
C. Statement I is true but Statement II is false .
D. Statement I is false but Statement II is true .

Explanation

To analyze the statements regarding hard water and its interaction with soap, we can break down the information as follows:

### Step 1: Understanding Hard Water
- Hard water is water that contains a high concentration of dissolved minerals, primarily calcium (Ca²⁺) and magnesium (Mg²⁺) ions.

### Step 2: Soap Composition
- Soap is a salt formed from the reaction of a fatty acid with an alkali. It typically contains sodium or potassium ions and a long hydrocarbon chain.

### Step 3: Interaction of Soap with Hard Water
- When soap is added to hard water, the calcium and magnesium ions present in the water react with the soap. This reaction leads to the formation of insoluble salts (precipitates), which do not dissolve in water.

### Step 4: Result of the Reaction
- Due to the formation of these insoluble precipitates, soap cannot effectively lather in hard water. Instead, it forms a scum or residue, which is why hard water does not produce lather.

### Conclusion
- **Statement I** is true: Hard water does not give lather with soap.
- **Statement II** is also true: Calcium and magnesium salts present in hard water form precipitate with soap.

### Final Evaluation
Both statements are correct and are related to each other. The presence of calcium and magnesium ions in hard water is the reason why soap does not lather.

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