GCSE Edexcel Atomic structure - Edexcel Calculating relative atomic mass - Higher Atoms consist of a nucleus containing protons and neutrons, surrounded by electrons in shells.

\({\%~of~an~element} = \frac{mass~of~an~element~in~the~compound}{relative~formula~mass~M_r} \times 100\) There are six atoms of hydrogen in the compound, so the mass ...