Question

Consider the decomposition of hydrogen peroxide in the reaction shown below.

2 H2O2
2 H2O + O2

How much O2 is produced when 34 grams of H2O2 reacts?

Group of answer choices

17 grams

34 grams

8 grams

16 grams

Answer 1

To find out how much \( O_2 \) is produced when 34 grams of \( H_2O_2 \) reacts, we need to start by determining how many moles of \( H_2O_2 \) we have and then use stoichiometry from the balanced chemical equation:

\[
2 \, H_2O_2 \rightarrow 2 \, H_2O + O_2
\]

1. **Calculate the molar mass of \( H_2O_2 \)**:
- The molar mass of hydrogen (\( H \)) = 1 g/mol
- The molar mass of oxygen (\( O \)) = 16 g/mol
- Molar mass of \( H_2O_2 = 2(1) + 2(16) = 2 + 32 = 34 \, g/mol \)

2. **Calculate the number of moles of \( H_2O_2 \) in 34 grams**:
\[
\text{Moles of } H_2O_2 = \frac{\text{Mass}}{\text{Molar mass}} = \frac{34 \, g}{34 \, g/mol} = 1 \, mol
\]

3. **Use the stoichiometry of the reaction**:
From the balanced equation, we see that 2 moles of \( H_2O_2 \) produce 1 mole of \( O_2 \). Therefore, 1 mole of \( H_2O_2 \) will produce:
\[
\text{Moles of } O_2 = \frac{1 \, mol \, H_2O_2}{2 \, mol \, H_2O_2} = 0.5 \, mol \, O_2
\]

4. **Convert moles of \( O_2 \) to grams**:
The molar mass of \( O_2 \) is:
\[
\text{Molar mass of } O_2 = 2(16) = 32 \, g/mol
\]
Now, calculate the mass of \( O_2 \) produced:
\[
\text{Mass of } O_2 = \text{Moles} \times \text{Molar mass} = 0.5 \, mol \times 32 \, g/mol = 16 \, g
\]

So, the amount of \( O_2 \) produced when 34 grams of \( H_2O_2 \) reacts is **16 grams**.

The correct answer is **16 grams**.