Calculate molarity of the resultant solution obtained by mixing 1 M and 2 .5 liter NaOH solution and 0.5 M 3 liter NaOH solution .

Options

A. 0.50 M
B. 0.73 M
C. 0.80 M
D. 1.0 M

Answer

To calculate the molarity of the resultant solution obtained by mixing two NaOH solutions, we can follow these steps:

### Step 1: Identify the given data
- Molarity of the first solution (M1) = 1 M
- Volume of the first solution (V1) = 2.5 L
- Molarity of the second solution (M2) = 0.5 M
- Volume of the second solution (V2) = 3 L

### Step 2: Calculate the total moles of NaOH in each solution
- Moles from the first solution (n1) = M1 × V1
\[ n1 = 1 \, \text{M} \times 2.5 \, \text{L} = 2.5 \, \text{moles} \]

- Moles from the second solution (n2) = M2 × V2
\[ n2 = 0.5 \, \text{M} \times 3 \, \text{L} = 1.5 \, \text{moles} \]

### Step 3: Calculate the total moles of NaOH in the resultant solution
- Total moles (n_total) = n1 + n2
\[ n_{\text{total}} = 2.5 \, \text{moles} + 1.5 \, \text{moles} = 4.0 \, \text{moles} \]

### Step 4: Calculate the total volume of the resultant solution
- Total volume (V_total) = V1 + V2
\[ V_{\text{total}} = 2.5 \, \text{L} + 3 \, \text{L} = 5.5 \, \text{L} \]

### Step 5: Calculate the molarity of the resultant solution
- Molarity of the resultant solution (M3) = n_total / V_total
\[ M3 = \frac{n_{\text{total}}}{V_{\text{total}}} = \frac{4.0 \, \text{moles}}{5.5 \, \text{L}} \approx 0.727 \, \text{M} \]

### Final Answer
The molarity of the resultant solution is approximately **0.727 M**.

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