428 mL of 10 M HCl and 572 mL of 3 M HCl are mixed. The molarity of the resulting solution is

Explanation

To find the molarity of the resulting solution when mixing two solutions of HCl, we can follow these steps:

### Step 1: Identify the volumes and molarities of the solutions.
- Volume of first solution (V1) = 428 mL
- Molarity of first solution (M1) = 10 M
- Volume of second solution (V2) = 572 mL
- Molarity of second solution (M2) = 3 M

### Step 2: Calculate the total volume of the resulting solution.
The total volume (V3) after mixing the two solutions is the sum of the individual volumes:
\[ V3 = V1 + V2 = 428 \, \text{mL} + 572 \, \text{mL} = 1000 \, \text{mL} \]

### Step 3: Calculate the total number of moles of HCl in each solution.
To find the total moles of HCl from each solution, we use the formula:
\[ \text{Moles} = \text{Molarity} \times \text{Volume} \]

For the first solution:
\[ \text{Moles from first solution} = M1 \times V1 = 10 \, \text{M} \times 0.428 \, \text{L} = 4.28 \, \text{moles} \]
(Note: Convert mL to L by dividing by 1000)

For the second solution:
\[ \text{Moles from second solution} = M2 \times V2 = 3 \, \text{M} \times 0.572 \, \text{L} = 1.716 \, \text{moles} \]

### Step 4: Calculate the total number of moles of HCl in the resulting solution.
\[ \text{Total moles of HCl} = \text{Moles from first solution} + \text{Moles from second solution} \]
\[ \text{Total moles of HCl} = 4.28 + 1.716 = 5.996 \, \text{moles} \]

### Step 5: Calculate the molarity of the resulting solution.
Molarity (M3) is calculated using the formula:
\[ M3 = \frac{\text{Total moles of solute}}{\text{Total volume of solution in liters}} \]
Since the total volume is 1000 mL (or 1 L):
\[ M3 = \frac{5.996 \, \text{moles}}{1 \, \text{L}} = 5.996 \, \text{M} \]

### Step 6: Round the result.
The final molarity of the resulting solution can be rounded to:
\[ M3 \approx 6 \, \text{M} \]

### Final Answer:
The molarity of the resulting solution is approximately **6 M**.

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