The metals that are employed in the battery industries are

A. $$\mathrm{Fe}$$

B. $$\mathrm{Mn}$$

C. $$\mathrm{Ni}$$

D. $$\mathrm{Cr}$$

E. $$\mathrm{Cd}$$

Choose the correct answer from the options given below:

The orange colour of $$\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7$$ and purple colour of $$\mathrm{KMnO}_4$$ is due to

Diamagnetic Lanthanoid ions are :

Which of the following acts as a strong reducing agent? (Atomic number: $$\mathrm{Ce}=58, \mathrm{Eu}=63, \mathrm{Gd}=64, \mathrm{Lu}=71$$)