Equations

• Relative formula mass (Mr) = sum of all relative atomic masses (Ar)
• relative atomic mass = (mass x abundance) + (mass x abundance) + ... / sum of all abundances
• percentage of element in a compound =Ar x number of atoms of the element / Mr of the compound x 100
• concentration = mass (g) / volume (dm3)
• Uncertainty = range / 2
• moles =mass (g) / Mr or Ar
• overall energy change = broken bonds − made bonds
• Mean rate of reaction = quantity of reactant or product / time
• Rf = distance of dot from start line / distance of solvent line from start line
• percentage change = change / original value x 100