To convert moles of helium to grams, you need to use the molar mass of helium. The molar mass of helium is approximately 4.00 grams per mole.
To find the mass in grams, you can use the formula:
Mass (g) = Moles × Molar Mass (g/mol)
For 0.202 mol of helium, the calculation would be:
Mass = 0.202 mol × 4.00 g/mol
When you perform the multiplication:
Mass = 0.808 grams
So, 0.202 moles of helium is equivalent to 0.808 grams.