25 volume' hydrogen peroxide means

Options

A. 100 mL marketed solution contains 25 g of `H_2O_2`.
B. 1 Lmarketed solution contains 75 g of `H_2O2.`
C. 1 L marketed solution contains 250 g of `H_2O_2.`
D. 1 L marketed solution contains 25 g of `H_2O_2`

Answer

To solve the question "25 volume hydrogen peroxide means", we need to understand what "25 volume" refers to in the context of hydrogen peroxide (H2O2).

### Step-by-step Solution:

1. **Understanding "Volume" in Chemistry**:
- The term "volume" in this context refers to the volume of gas produced by a given volume of liquid solution when it decomposes. Specifically, "25 volume" means that 1 liter of the hydrogen peroxide solution will produce 25 liters of oxygen gas (O2) when it decomposes.

2. **Decomposition Reaction of Hydrogen Peroxide**:
- The decomposition of hydrogen peroxide can be represented by the following balanced chemical equation:
\[ 2 \text{H}_2\text{O}_2 \rightarrow 2 \text{H}_2\text{O} + \text{O}_2 \]
- From this equation, we can see that 2 moles of H2O2 produce 1 mole of O2.

3. **Calculating Moles of O2 Produced**:
- At standard temperature and pressure (STP), 1 mole of any gas occupies 22.4 liters. Therefore, if 1 liter of H2O2 produces 25 liters of O2, we can calculate the moles of O2 produced:
\[ \text{Moles of O}_2 = \frac{25 \text{ liters}}{22.4 \text{ liters/mole}} \approx 1.116 \text{ moles} \]

4. **Relating Moles of H2O2 to Moles of O2**:
- From the balanced equation, we know that 2 moles of H2O2 produce 1 mole of O2. Therefore, the moles of H2O2 required to produce 1.116 moles of O2 is:
\[ \text{Moles of H}_2\text{O}_2 = 2 \times 1.116 \approx 2.232 \text{ moles} \]

5. **Calculating Mass of H2O2**:
- The molar mass of H2O2 is approximately 34 g/mol. Thus, the mass of H2O2 can be calculated as follows:
\[ \text{Mass of H}_2\text{O}_2 = 2.232 \text{ moles} \times 34 \text{ g/mol} \approx 75.89 \text{ grams} \]

6. **Conclusion**:
- Therefore, in a 1-liter marketed solution of hydrogen peroxide, there are approximately 75 grams of H2O2. This corresponds to option 2 in the provided choices.

### Final Answer:
- **The correct answer is**: 1 liter marketed solution contains 75 gm H2O2.