When observed under standard laboratory conditions, which of the following aqueous transition metal β d and f Block Elements Chemistry Question
Question
When observed under standard laboratory conditions, which of the following aqueous transition metal ionic species are perfectly matched with their distinctly characteristic solution colours?
π‘ Solution & Explanation
The colours of transition metal ions heavily depend on the specific $d$ -electron count allowing $d-d$ transitions. $V^{3+}$ ($d^2$) is characteristically green; $Mn^{2+}$ ($d^5$, high spin) is very faintly pink; $Fe^{3+}$ ($d^5$) typically appears yellow-brown in aqueous solution due to hydrolysis complexes. However, $Ti^{4+}$ ($d^0$) possesses no $d$ -electrons to undergo any excitation, rendering it perfectly colourless, not purple.