`KCl.MgCl_2. 6H_2O` is a

Options

A. mixed salt
B. double salt
C. basic salt
D. complex salt

Answer

To determine the type of salt represented by the formula `KCl.MgCl2.6H2O`, we will analyze the components of the salt and categorize it based on the definitions of mixed salts, double salts, basic salts, and complex salts.

### Step-by-step Solution:

1. **Identify the Components of the Salt**:
- The formula `KCl.MgCl2.6H2O` consists of potassium chloride (KCl), magnesium chloride (MgCl2), and water of crystallization (6H2O).

2. **Understand the Definitions**:
- **Mixed Salt**: A salt formed from more than one acid or base. Example: Sodium Potassium Sulfate (Na2SO4.K2SO4).
- **Double Salt**: A salt that contains more than one cation or anion. Example: Mohr's salt (NH4Fe(SO4)2.12H2O).
- **Basic Salt**: Formed when a strong base reacts with a weak acid, resulting in a salt that retains some basic properties. Example: Sodium bicarbonate (NaHCO3).
- **Complex Salt**: Contains a central metal ion surrounded by neutral or negatively charged ions, which do not fully dissociate in solution. Example: [Cu(NH3)4]SO4.

3. **Analyze the Given Salt**:
- In `KCl.MgCl2.6H2O`, we see that it contains two different cations: K+ (from KCl) and Mg2+ (from MgCl2). The anion is Cl- from both components.

4. **Determine the Type of Salt**:
- Since there are more than one cation (K+ and Mg2+) present in the salt, it fits the definition of a **double salt**.
- It does not fit the definitions of mixed salt, basic salt, or complex salt based on the definitions provided.

5. **Conclusion**:
- Therefore, `KCl.MgCl2.6H2O` is classified as a **double salt**.

### Final Answer:
`KCl.MgCl2.6H2O` is a double salt.

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