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

Options

A. Because of the large size of the Ln (III) ions, the bonding in its compounds is predominantly ionic in character
B. The ionic sizes of Ln(III) decrease in general with increasing atomic number
C. Ln(III) compounds are generally colourless
D. Ln(III) hydroxide are mainly basis in character

Answer

C

Explanation

The most common oxidation state of lanthanoid is `+3`.
Lanthanoids in `+3` oxidation state usually have unpaired electron in `f`- subshell and impart characteristic colour in solid as well as in solution due to `f-f` transition. (Except lanthanum and lutetium).