Understanding Mass Percent

Oct 13, 2025 by wbrum.org 22 views

What is the Mass Percent of Oxygen in SO2?

Understanding Mass Percent

Mass percent is a measure of the amount of a particular element in a compound. It is calculated by dividing the mass of the element by the total mass of the compound and then multiplying by 100. In this case, we are interested in finding the mass percent of oxygen in the compound SO2.

Calculating Mass Percent of Oxygen in SO2

To calculate the mass percent of oxygen in SO2, we need to know the atomic masses of sulfur (S) and oxygen (O). The atomic mass of sulfur is 32.1 g/mol, and the atomic mass of oxygen is 16.0 g/mol.

The formula for SO2 is S + 2O. Therefore, the total mass of the compound is the sum of the atomic masses of sulfur and two oxygen atoms.

Step 1: Calculate the Total Mass of SO2

The total mass of SO2 is the sum of the atomic masses of sulfur and two oxygen atoms.

total_mass_SO2 = atomic_mass_S + (2 * atomic_mass_O)
total_mass_SO2 = 32.1 g/mol + (2 * 16.0 g/mol)
total_mass_SO2 = 32.1 g/mol + 32.0 g/mol
total_mass_SO2 = 64.1 g/mol

Step 2: Calculate the Mass of Oxygen in SO2

The mass of oxygen in SO2 is the sum of the atomic masses of two oxygen atoms.

mass_O_SO2 = 2 * atomic_mass_O
mass_O_SO2 = 2 * 16.0 g/mol
mass_O_SO2 = 32.0 g/mol

Step 3: Calculate the Mass Percent of Oxygen in SO2

Now that we have the total mass of SO2 and the mass of oxygen in SO2, we can calculate the mass percent of oxygen in SO2.

mass_percent_O_SO2 = (mass_O_SO2 / total_mass_SO2) * 100
mass_percent_O_SO2 = (32.0 g/mol / 64.1 g/mol) * 100
mass_percent_O_SO2 = 0.5 * 100
mass_percent_O_SO2 = 50%

Conclusion

The mass percent of oxygen in SO2 is 50%. This means that 50% of the mass of SO2 is oxygen.

Answer

The correct answer is A. $\frac{32.1 \, \text{g}}{16.0 \, \text{g} + 16.0 \, \text{g}} \times 100\%$ .

Discussion

The mass percent of oxygen in SO2 can be calculated using the formula:

mass_percent_O_SO2 = (mass_O_SO2 / total_mass_SO2) * 100

Where mass_O_SO2 is the mass of oxygen in SO2 and total_mass_SO2 is the total mass of SO2.

The mass percent of oxygen in SO2 is an important property of the compound, as it can affect its reactivity and other chemical properties.

Key Points

Mass percent is a measure of the amount of a particular element in a compound.
The mass percent of oxygen in SO2 is 50%.
The mass percent of oxygen in SO2 can be calculated using the formula: mass_percent_O_SO2 = (mass_O_SO2 / total_mass_SO2) * 100.

References

Atomic masses of elements: https://en.wikipedia.org/wiki/Atomic_mass
Formula for SO2: https://en.wikipedia.org/wiki/Sulfur_dioxide