• # question_answer Which one of the following ions exhibits colour in aqueous solution? A) $T{{i}^{4+}}$                              B) $Z{{n}^{2+}}$      C)   $N{{i}^{2+}}$                  D)   $S{{c}^{3+}}$

$T{{i}^{4+}},Z{{n}^{2+}},S{{c}^{3+}}$are not carrying unpaired electrons. But$N{{i}^{2+}}$with ${{d}^{8}},$electronic configuration carry two unpaired electrons. So it is colored. Hence, the correct option is (c).