For this you don't need to have the atomic mass. Take the number of atoms and divide it by Avogadro's constant, 6.02 × 1023. Multiply by one mole for units to cancel. 20.00 atoms Au / (6.02 × 1023...
No of moles of atoms={total mass of substance(or)total mass of molecules }x# gram molecular weight of one molecule Where # =atomicity of molecule i.e no.of atoms in a molecule ex: atomicity of co2=3...
You should find an agent because au pairs have special employee status. Many countries have arrangements for 'cultural exchange' and au pairs fall into this category. You are not their employer...