Which of the following statements is wrong regarding Lanthanides?
$\text{Ln}^{3+}$ compounds are generally colorless.
$\text{Ln}^{3+}$ compounds are predominantly ionic in character.
The ionic size of $\text{Ln}^{3+}$ ions decreases with increasing atomic number.
$\text{Ln}^{3+}$ hydroxides are mainly basic in nature.
