Answer:
There are 0.195 moles.
Explanation:
1 mol of any gas under STP (meaning 1 atm and 273 K) will occupy 22.4 liters.
With the information above in mind, we can calculate how many moles will occupy 4.38 liters:
In 4.38 liters of a gas at STP there will be 0.195 moles.