The `w//w %` of 25 g of calcium hydroxide in 50 g of solvent of __________`%`.

Options

A. 40
B. 33.33
C. 36.3
D. 30

Answer

To find the weight by weight percentage (w/w %) of calcium hydroxide in the solution, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Mass of Solute and Solvent**:
- The mass of the solute (calcium hydroxide) is given as 25 g.
- The mass of the solvent is given as 50 g.

2. **Calculate the Mass of the Solution**:
- The mass of the solution is the sum of the mass of the solute and the mass of the solvent.
- Mass of solution = Mass of solute + Mass of solvent
- Mass of solution = 25 g + 50 g = 75 g

3. **Use the Weight by Weight Percentage Formula**:
- The formula for weight by weight percentage is:
\[ \text{w/w \%} = \left( \frac{\text{mass of solute}}{\text{mass of solution}} \right) \times 100 \]

4. **Substitute the Values into the Formula**:
- Substitute the mass of the solute and the mass of the solution into the formula:
\[ \text{w/w \%} = \left( \frac{25 \text{ g}}{75 \text{ g}} \right) \times 100 \]

5. **Calculate the Percentage**:
- Calculate the fraction:
\[ \frac{25}{75} = \frac{1}{3} \]
- Now multiply by 100 to get the percentage:
\[ \text{w/w \%} = \frac{1}{3} \times 100 = 33.33\% \]

### Final Answer:
The weight by weight percentage of calcium hydroxide in the solution is **33.33%**.

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