Question

Which of the following complex ion is expected to absorb visible light?

• A. ${\left[Sc{\left(H_{2}O\right)}_3{\left(N{H}_3\right)}_3\right]}^{3+}$
• B. ${\left[Ti(en{)}_2{\left(N{H}_3\right)}_2\right]}^{4+}$
• C. ${\left[Cr{\left(N{H}_3\right)}_6\right]}^{3+}$
• D. ${\left[Zn{\left(N{H}_3\right)}_6\right]}^{2+}$

Answer 1

Answer: (C)

${\left[Sc{\left(H_{2}O\right)}_3{\left(N{H}_3\right)}_3\right]}^{3+}$	${\left[Ti(en{)}_2{\left(N{H}_3\right)}_2\right]}^{4+}$	${\left[Cr{\left(N{H}_3\right)}_6\right]}^{3+}$	${\left[Zn{\left(N{H}_3\right)}_6\right]}^{+2}$
x = +3	x =+4	x = +3	x= +2
d electrons = 0	d electrons = 0	d electrons = 3	d electrons = 10
$\therefore$ No absorption of visible light	$\therefore$ No absorption of visible light	$\therefore$ complex ion is expected to absorb visible light	$\therefore$ No absorption of visible light.