Q. Which of the following metal ions is not coloured?
A) ${Ti}^{3 +}$
B) ${Fe}^{3 +}$
C) $V^{2 +}$
D) ${Zn}^{2 +}$
Explanation
(d)
${Zn}^{2 +}$ ion possess $(n - 1)d^{10\ }$configuration. There are no unpaired electrons in $(n - 1)\ d$- subshell due to which $d - d$ transitions are not possible. Hence, ${Zn}^{2 +}$ ions are colourless.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.