College

Sarah measures out 151 grams of [tex]$SO_2$[/tex]. How many moles is this? Express your answer to three significant figures.

151 grams of [tex]$SO_2$[/tex] is equal to [tex]\square[/tex] moles.

Answer :

To find out how many moles are in 151 grams of [tex]\( SO_2 \)[/tex], you can follow these steps:

1. Find the Molar Mass of [tex]\( SO_2 \)[/tex]:
- Sulfur (S) has an atomic mass of approximately 32.07 grams/mole.
- Oxygen (O) has an atomic mass of approximately 16.00 grams/mole.
- Since [tex]\( SO_2 \)[/tex] has one sulfur atom and two oxygen atoms, the molar mass is calculated as follows:
[tex]\[
\text{Molar mass of } SO_2 = 32.07 + 2 \times 16.00 = 64.07 \text{ grams/mole}
\][/tex]

2. Calculate the Number of Moles:
The formula to calculate the number of moles from the mass is:
[tex]\[
\text{Number of moles} = \frac{\text{Mass in grams}}{\text{Molar mass in grams/mole}}
\][/tex]
So for 151 grams of [tex]\( SO_2 \)[/tex]:
[tex]\[
\text{Number of moles} = \frac{151 \text{ grams}}{64.07 \text{ grams/mole}} \approx 2.357
\][/tex]

Therefore, 151 grams of [tex]\( SO_2 \)[/tex] is equal to approximately 2.357 moles.