\b[The valence configurations are $\mathrm C:2s^22p^2$, $\mathrm{Si}:3s^23p^2$, and $\mathrm{Pb}:6s^26p^2$.] Their full closed-shell cores are respectively $[\mathrm{He}]$, $[\mathrm{Ne}]$, and $[\mathrm{Xe}]4f^{14}5d^{10}$. The filled 4f and 5d subshells of <lead> are not the outer valence configuration requested.

Solution

Past exam of the chemistry course of the year 1 of the natural sciences course of the University of Cambridge / 2023 / Paper 1 / 6 / b / i / Solution

 Solution (source code)