`1` litre of `30` volume-hydrogen peroxide contains `91.07g H_2O_2`.

Explanation

To determine whether the statement "1 litre of 30 volume hydrogen peroxide contains 91.07g H₂O₂" is true or false, we can follow these steps:

### Step 1: Understand the concept of volume strength
Volume strength of hydrogen peroxide indicates the volume of oxygen gas released when 1 volume of hydrogen peroxide decomposes. For instance, 1 volume of H₂O₂ releases 5.6 volumes of O₂.

### Step 2: Calculate the normality of 30 volume hydrogen peroxide
We know that:
- 5.6 volume of H₂O₂ corresponds to 1 normality (N).
- Therefore, for 30 volume of H₂O₂, we can calculate the normality as follows:

\[ \text{Normality} = \frac{30}{5.6} \text{ N} \]

### Step 3: Calculate the molarity from normality
Normality (N) is related to molarity (M) by the equation:
\[ \text{Normality} = \text{Molarity} \times n \text{ factor} \]
For hydrogen peroxide (H₂O₂), the n factor is 2 (since it can donate 2 moles of electrons). Thus, we can express molarity as:
\[ \text{Molarity} = \frac{\text{Normality}}{n \text{ factor}} = \frac{\frac{30}{5.6}}{2} \]

### Step 4: Calculate the number of moles in 1 litre
Using the molarity we calculated, we can find the number of moles (n) in 1 litre:
\[ \text{Number of moles} = \text{Molarity} \times \text{Volume in litres} = \left(\frac{30}{5.6 \times 2}\right) \times 1 \]

### Step 5: Calculate the molecular weight of hydrogen peroxide
The molecular weight of H₂O₂ can be calculated as follows:
- Atomic mass of H = 1 (there are 2 H atoms)
- Atomic mass of O = 16 (there are 2 O atoms)

\[ \text{Molecular weight of H₂O₂} = (2 \times 1) + (2 \times 16) = 2 + 32 = 34 \text{ g/mol} \]

### Step 6: Calculate the mass of hydrogen peroxide
Now, we can find the mass of hydrogen peroxide using the number of moles and its molecular weight:
\[ \text{Mass of H₂O₂} = \text{Number of moles} \times \text{Molecular weight} = \left(\frac{30}{5.6 \times 2}\right) \times 34 \]

### Step 7: Solve for the mass
Now, we can simplify and calculate:
\[ \text{Mass of H₂O₂} = \left(\frac{30}{11.2}\right) \times 34 \approx 91.07 \text{ g} \]

### Conclusion
Since we calculated the mass of hydrogen peroxide to be approximately 91.07 grams, we can conclude that the statement is true.