Potassium permanganate is used _____.

 

Which of the following is Baeyer's reagent?

Lanthanoids are ______.

The atomic number of cerium $\left(\mathrm{Ce}\right)$ is $58$. The correct electronic configuration of the ${\text{Ce}}^{\text{3+}}$ ion is _____.

Gadolinium belongs to $4\mathrm{f}$series. Its atomic number is $64$. Which of the following is the correct electronic configuration of gadolinium?

Which one of the following lanthanide ions does not exhibit paramagnetism?

What is the general molecular formula of the product obtained on heating lanthanoids ($\mathrm{Ln}$) with sulphur?

The reason of the lanthanoid contraction is _____.

In f-block elements, the atomic radius almost remains same because of the _____.