Okay, you've given me the Mass of the sample, which is 22g. Now, in order to convert a mass into a mol, you'll require something known as the Molar Mass. Which is the mass of an element in g/mol (basically a relative scale of mass to the elements).
mass = mol x molar mass, therefore
mol = mass/molar mass, {{the molar mass of Ar is 39.95 g/mol}}
mol = 22g/39.95g/mol, {{ The grams cancel out}}
mol = 0.55 mols Argon
