Merry Christmas to all Chemstuff followers!

Over the next 12 days get ready for 12 christmas presents of chemical calculations (You can’t say I never treat you to anything!) Please show your working as much as possible & I look forward to receiving your answers! 🙂

Relative Atomic Mass

Find the relative atomic masses of these elements

1. Argon
2. Fluorine
3. Neptunium
4. Germanium
5. Arsenic

Relative Molecular Mass

Find the relative molecular (or formula) masses of these compounds

1. Water (H₂O)
2. Methane (CH₄)
3. Rubidium chloride (RbCl)
4. Selenium Oxide (SeO₂)
5. Aluminium Carbonate (Al₂(CO₃)₃)