Question

A balloon contains 12.1 L of helium gas at STP. What is the mass in grams of He in the balloon?

Answer 1

Answer:\

1.08 grams

Step-by-step explanation:

first, we need to find the number of moles

we divide 12.1/22.4=0.54 moles

we multiply the number of moles with the molecular mass 0.54x2=1.08g