Sulfuric acid (H2SO4 Molar Mass = 98.1) can be prepared from S8, O2 and H2O by the following series of reactions. Balance!
S8 + 8O2 -> 8SO2
2SO2 + O2 -> 2SO3
SO3 + H2O -> H2SO4
What volume of sulfuric acid is produced from reacting 70.0 grams sulfur with sufficient oxygen and water?
(Specify gravity sulfuric acid = 1.12)
The correct answer and explanation is :
To calculate the volume of sulfuric acid produced from 70.0 grams of sulfur (S8), we will proceed step by step using stoichiometry and the chemical equations provided. Here’s the breakdown:
1. Balanced Reactions
The chemical reactions provided are:
- Sulfur to sulfur dioxide (SO2):
[
S_8 + 8O_2 \rightarrow 8SO_2
] - Sulfur dioxide to sulfur trioxide (SO3):
[
2SO_2 + O_2 \rightarrow 2SO_3
] - Sulfur trioxide to sulfuric acid (H2SO4):
[
SO_3 + H_2O \rightarrow H_2SO_4
]
2. Molar Mass of Sulfur (S8)
The molar mass of sulfur is 32.07 g/mol. For the molecule ( S_8 ), the molar mass is:
[
\text{Molar Mass of } S_8 = 32.07 \times 8 = 256.56 \, \text{g/mol}
]
3. Moles of Sulfur (S8)
To determine how many moles of sulfur are in 70.0 grams, we use the formula:
[
\text{moles of } S_8 = \frac{\text{mass of sulfur}}{\text{molar mass of } S_8}
]
[
\text{moles of } S_8 = \frac{70.0 \, \text{g}}{256.56 \, \text{g/mol}} \approx 0.2735 \, \text{mol}
]
4. Moles of Sulfuric Acid (H2SO4)
Next, we calculate how many moles of sulfuric acid (H2SO4) are produced. From the reactions, the stoichiometric relationship is 1 mole of ( S_8 ) produces 1 mole of ( H_2SO_4 ). Therefore, the moles of ( H_2SO_4 ) produced is:
[
\text{moles of H}_2\text{SO}_4 = 0.2735 \, \text{mol}
]
5. Mass of Sulfuric Acid
The molar mass of sulfuric acid (H2SO4) is 98.1 g/mol. Thus, the mass of sulfuric acid produced is:
[
\text{mass of H}_2\text{SO}_4 = \text{moles of H}_2\text{SO}_4 \times \text{molar mass of H}_2\text{SO}_4
]
[
\text{mass of H}_2\text{SO}_4 = 0.2735 \, \text{mol} \times 98.1 \, \text{g/mol} \approx 26.8 \, \text{g}
]
6. Volume of Sulfuric Acid
Given the density of sulfuric acid is 1.12 g/mL, we can now calculate the volume of sulfuric acid produced using the formula:
[
\text{volume of H}_2\text{SO}_4 = \frac{\text{mass of H}_2\text{SO}_4}{\text{density of H}_2\text{SO}_4}
]
[
\text{volume of H}_2\text{SO}_4 = \frac{26.8 \, \text{g}}{1.12 \, \text{g/mL}} \approx 23.93 \, \text{mL}
]
Conclusion
Thus, from 70.0 grams of sulfur, approximately 23.93 mL of sulfuric acid is produced, assuming sufficient oxygen and water are available for the reactions.