Multiple choice Which of the following sets contains colourless aquated transition metal ions? Sc3+, Ti3+, Zn2+ Sc3+, Ti4+, Cu2+ Sc3+, Ti4+, Zn2+ Ti3+, V4+, Zn2+ Al3+, B3+, Si4+ Reveal answer Fill a bubble to check yourself C Correct answer Explanation Yes, all have no unpaired electrons, hence all are colourless.