This Study Mind Tutorial covers the following specification points:

CIE: 1.1.3, 1.1.6, 1.2.2

1.1.3. know what is meant by the terms ‘atomic (proton) number’ and ‘mass number’ 

1.1.6. be able to define the terms ‘relative isotopic mass’ and ‘relative atomic mass’, based on the ¹²C scale

1.2.2. understand the effects that ionic radius and ionic charge have on the strength of ionic bonding