Temporary hardness may be removed from water adding.

Options

A. `CaCO_(3)`
B. `Ca(OH)_(2)`
C. `CaSO_(4)`
D. HCl

Answer

To solve the question regarding the removal of temporary hardness from water, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Temporary Hardness**:
- Temporary hardness in water is primarily caused by the presence of calcium bicarbonate (Ca(HCO₃)₂) and magnesium bicarbonate (Mg(HCO₃)₂). This type of hardness can be removed by boiling the water.

2. **Identify the Method for Removal**:
- The common method to remove temporary hardness is known as Clarke's method. This involves the addition of calcium hydroxide (Ca(OH)₂), also known as slaked lime, to the water.

3. **Chemical Reaction**:
- When calcium hydroxide is added to water containing calcium bicarbonate, a chemical reaction occurs:
\[ \text{Ca(HCO}_3\text{)}_2 + \text{Ca(OH)}_2 \rightarrow \text{CaCO}_3 \downarrow + \text{H}_2\text{O} \]
- In this reaction, calcium carbonate (CaCO₃) is formed as a precipitate, which is insoluble in water. The water becomes free from temporary hardness as the precipitate can be removed.

4. **Evaluate the Options**:
- Given the options:
- A) Calcium Carbonate
- B) Calcium Hydroxide
- C) Calcium Sulfate
- D) HCl
- From the above analysis, we can conclude that the correct answer is **B) Calcium Hydroxide**.

5. **Final Answer**:
- Therefore, the correct option for removing temporary hardness from water is **Calcium Hydroxide**.