[填空题]
Scandium is a transition metalwcfk2kw 9g p;dhm-/c,d*p:xb that can form both 1 y:c s+3ibqv/zymppm pv7 .j;2+ and 3+ complexes.
1.Draw the electron in boxes notation for the 4s4s and 3d3d electrons in an Sc$^{2+}$ ion.Sc$^{2+}$(g)$\rightarrow$Sc$^{x+}$(g)+e-, x=
2.State the equation for the third ionization energy of scandium, and indicate which electron is lost.
3.Explain why $[Sc(H_2O)_6]^{2+}$ is coloured whereas $[Sc(H_2O)_6]^{3+}$ forms a colourless aqueous solution.
