Knowing that the chemistry of lanthanoids(Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect?

Because of the large size of the Ln(III) ions the bonding in its compounds is predominantly ionic in character

Ln(III) compounds are generally colourless

The ionic sizes of Ln(III) decrease in general with increasing atomic number

Ln(III) hydroxides are mainly basic in character