5.22 moles of helium have a mass of 20.9 g.
The molar mass is the sum of the total mass in grams of all the atoms that make up a mole of a particular molecule.
We have 5.22 moles of helium and we want to convert it to grams. We will use the following expression.
m = n × M
m = 5.22 mol × 4.00 g/mol = 20.9 g
where,
5.22 moles of helium have a mass of 20.9 g.
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