Answer:
![\boxed {\boxed {\sf 4.522 \ mol}}](https://img.qammunity.org/2022/formulas/chemistry/college/7a825jni4z13wt0njerrykfv88jbcqg47k.png)
Step-by-step explanation:
We are asked to find how many moles of gas occupy a volume of 101.3 liters.
1 mole of any gas at STP (standard temperature and pressure) has a volume of 22.4 liters. We can use this information to make a proportion.
![\frac {1 \ mol}{22.4 \ L}](https://img.qammunity.org/2022/formulas/chemistry/college/zj87ku3spsxfumg61cus1fa47rsoxriv5s.png)
We are converting 101.3 liters to moles, so we multiply the proportion by that value.
![101.3 \ L *\frac {1 \ mol}{22.4 \ L}](https://img.qammunity.org/2022/formulas/chemistry/college/sxg0ftttab63pa4tf98i23olrwm6h9b23w.png)
The units of liters (L) cancel.
![101.3 *\frac {1 \ mol}{22.4}](https://img.qammunity.org/2022/formulas/chemistry/college/l0y2mvmlo5cfl1j686fkiqv6yblgt4cq8b.png)
![\frac {101.3}{22.4} \ mol](https://img.qammunity.org/2022/formulas/chemistry/college/dms4001aqw6jurxwe772mkxaody4huld08.png)
Divide.
![4.52232143 \ mol](https://img.qammunity.org/2022/formulas/chemistry/college/8atixqxfabzt16tm8l6cakrjn4is7sa6m0.png)
The original value of liters (101.3 L) has 4 significant figures, so our answer must have the same. For the number we calculated, that is the thousandths place. The 3 in the ten-thousandths place to the right tells us to leave the 2 in the thousandths place.
![4.522 \ mol](https://img.qammunity.org/2022/formulas/chemistry/college/h2snfzs1u34ohd1je7hecu7sn3eaxki3b2.png)
101.3 liters of gas is equal to approximately 4.522 moles of gas.