Final answer:
In naming metal cations, '-ous' denotes the smaller charge and '-ic' denotes the larger charge, like in 'ferrous' for iron(II) and 'ferric' for iron(III).
Step-by-step explanation:
In naming metal cations, the -ous suffix is used for the smaller charge, and the -ic suffix is used for the larger charge. This rule applies to the common naming system for elements that can form more than one cation, traditionally those that are transition metals.
For example, iron(II) ion would be called ferrous ion, indicating a smaller charge, whereas iron(III) ion would be referred to as ferric ion, indicating a larger charge.