The percentage of lanthanides and iron,respectively,in misch metal are

Which of the following statements is incorrect?

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

The ionic radius of $La^{3+}$ is $1.06 \ \mathop{A}\limits^o$. Which of the following is the closest value for the ionic radius of $Lu^{3+}$ in $\mathop{A}\limits^o$? $(Lu = 71, La = 57)$

All those elements belong to $f-$block whose atomic numbers are

Which of the following hydroxides is the most basic?