What is the mass percent of oxygen $( O )$ in $SO _2$ ?
A. $\frac{(16.0 g+16 g)(6.02 \times 10^{23})}{100 g}$
B. $\frac{32.1 g}{16.0 g+16.0 g} \times 100 \%$
C. $\frac{16.0 g}{(32.1 g+16.0 g+16.0 g)} \times 100 \%$
D. $\frac{(16.0 g+16.0 g)}{(32.1 g+16.0 g+16.0 g)} \times 100 \%$
Answer (2)
Calculate the molar mass of S O 2 as 32.1 + 2 ( 16.0 ) g/mol.
Calculate the mass of oxygen in S O 2 as 2 ( 16.0 ) g/mol.
Determine the mass percent of oxygen in S O 2 using the formula molar mass of S O 2 mass of oxygen × 100% .
The mass percent of oxygen in S O 2 is ( 32.1 g + 16.0 g + 16.0 g ) ( 16.0 g + 16.0 g ) × 100% .
Explanation
Understanding the Problem We want to find the mass percent of oxygen in S O 2 . This means we need to determine what percentage of the total mass of S O 2 is made up of oxygen.
Calculating Molar Mass of Sulfur Dioxide First, we need to calculate the molar mass of S O 2 . The molar mass of sulfur (S) is approximately 32.1 g/mol, and the molar mass of oxygen (O) is approximately 16.0 g/mol. Since there are two oxygen atoms in S O 2 , the molar mass of S O 2 is calculated as follows: 3. Calculating Mass of Oxygen in Sulfur Dioxide Next, we calculate the total mass of oxygen in one mole of $SO_2$. Since there are two oxygen atoms, the total mass of oxygen is:"> M_{SO_2} = M_S + 2 "> 3. Calculating Mass of Oxygen in Sulfur Dioxide Next, we calculate the total mass of oxygen in one mole of $SO_2$. Since there are two oxygen atoms, the total mass of oxygen is: m_O = 2 ">
Calculating Mass Percent of Oxygen Now, we can calculate the mass percent of oxygen in S O 2 using the formula: 5. Substituting Values Substituting the values we calculated:"> Mass percent of O = M S O 2 m O " > 5. S u b s t i t u t in g Va l u es S u b s t i t u t in g t h e v a l u es w ec a l c u l a t e d : \text{Mass percent of O} = \frac{2 ">
Final Answer Comparing this expression with the given options, we see that option D matches our calculated expression. Therefore, the correct answer is: D. ( 32.1 g + 16.0 g + 16.0 g ) ( 16.0 g + 16.0 g ) × 100%
Examples
In environmental science, determining the mass percent of elements in compounds like S O 2 is crucial for assessing air quality and pollution levels. For example, knowing the oxygen content in S O 2 helps scientists understand its reactivity and potential to form acid rain. This calculation is a fundamental step in evaluating the environmental impact of industrial emissions and developing strategies for pollution control. By understanding the composition of pollutants, we can better mitigate their harmful effects on ecosystems and human health.
To find the mass percent of oxygen in S O 2 , we calculated the total molar mass of the compound and the mass contributed by oxygen. The correct expression from the options provided that matches our calculation is option D. Therefore, the mass percent of oxygen in S O 2 is given by D.
;
