4 litres of water are added to 2L of 6 molar HCl solutions.What is the molarity of resulting solution?

Explanation

To solve the problem of finding the molarity of the resulting solution after adding 4 liters of water to 2 liters of 6 molar HCl solution, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Initial Conditions**:
- Initial volume of HCl solution (V1) = 2 liters
- Initial molarity of HCl solution (M1) = 6 molar

2. **Calculate Final Volume**:
- When 4 liters of water are added to the 2 liters of HCl solution, the final volume (V2) is:
\[ V2 = V1 + \text{Volume of water} = 2 \, \text{liters} + 4 \, \text{liters} = 6 \, \text{liters} \]

3. **Use the Dilution Formula**:
- The relationship between the initial and final conditions can be expressed using the dilution formula:
\[ M1 \times V1 = M2 \times V2 \]
- Here, M2 is the final molarity we want to find.

4. **Substitute Known Values**:
- Substitute the known values into the equation:
\[ 6 \, \text{mol/L} \times 2 \, \text{L} = M2 \times 6 \, \text{L} \]

5. **Calculate Molarity (M2)**:
- Calculate the left side:
\[ 12 \, \text{mol} = M2 \times 6 \, \text{L} \]
- Now, solve for M2:
\[ M2 = \frac{12 \, \text{mol}}{6 \, \text{L}} = 2 \, \text{mol/L} \]

6. **Final Answer**:
- The molarity of the resulting solution is **2 molar**.