Answer :
To find out how many moles 151 grams of sulfur dioxide (SO₂) is, we can follow these steps:
1. Calculate the Molar Mass of SO₂:
- To find the molar mass, we add up the atomic masses of all the atoms in a molecule of sulfur dioxide (SO₂).
- Sulfur (S) has an atomic mass of approximately 32.07 g/mol.
- Oxygen (O) has an atomic mass of approximately 16.00 g/mol.
- Since there are two oxygen atoms in SO₂, their combined mass is [tex]\(2 \times 16.00 = 32.00\)[/tex] g/mol.
- Therefore, the molar mass of SO₂ is [tex]\(32.07 + 32.00 = 64.07\)[/tex] g/mol.
2. Use the Formula to Find Moles:
- The number of moles of a substance can be found using the formula:
[tex]\[
\text{moles} = \frac{\text{mass in grams}}{\text{molar mass in g/mol}}
\][/tex]
- For SO₂, given that the mass is 151 grams, we plug in the values:
[tex]\[
\text{moles of SO₂} = \frac{151}{64.07}
\][/tex]
3. Calculate and Round the Answer:
- Performing the division gives us the number of moles of SO₂.
- [tex]\(\approx 2.357\)[/tex] moles.
Thus, 151 grams of SO₂ is approximately 2.357 moles when rounded to three significant figures.
1. Calculate the Molar Mass of SO₂:
- To find the molar mass, we add up the atomic masses of all the atoms in a molecule of sulfur dioxide (SO₂).
- Sulfur (S) has an atomic mass of approximately 32.07 g/mol.
- Oxygen (O) has an atomic mass of approximately 16.00 g/mol.
- Since there are two oxygen atoms in SO₂, their combined mass is [tex]\(2 \times 16.00 = 32.00\)[/tex] g/mol.
- Therefore, the molar mass of SO₂ is [tex]\(32.07 + 32.00 = 64.07\)[/tex] g/mol.
2. Use the Formula to Find Moles:
- The number of moles of a substance can be found using the formula:
[tex]\[
\text{moles} = \frac{\text{mass in grams}}{\text{molar mass in g/mol}}
\][/tex]
- For SO₂, given that the mass is 151 grams, we plug in the values:
[tex]\[
\text{moles of SO₂} = \frac{151}{64.07}
\][/tex]
3. Calculate and Round the Answer:
- Performing the division gives us the number of moles of SO₂.
- [tex]\(\approx 2.357\)[/tex] moles.
Thus, 151 grams of SO₂ is approximately 2.357 moles when rounded to three significant figures.