What is the amount in moles of 4.82 x 10^22 atoms of Chlorine

one mole of chlorine atoms = 2x6.02x10^23 atoms
so mole in 4.82x10^22 = 4.82 x10^22/2x6.02x10^23 = 0.4 mole

There might be a bit of a trick here. Remember that chlorine gas is Cl2, so the answer might be half of what you expected. So, 0.4 mol of Cl atoms but 0.2 mole of Cl2 molecules.

Just sayin'