Q.State the general valence-shell electronic configuration of the p-block elements, and write out the specific configurations for the outermost shell of Group 13 (boron family) and Group 14 (carbon family). Which sub-shell is being progressively filled across the p-block?

[!TLDR] The p-block runs from $ns^2np^1$ (Group 13) to $ns^2np^6$ (Group 18), each group adding one more p-electron; Group 13 ends in $ns^2np^1$ and Group 14 in $ns^2np^2$. [!ANSWER] Group 13's outer configuration is $ns^2np^1$ and Group 14's is $ns^2np^2$; across the whole p-block the $p$ sub-shell is being progressively filled from $np^1$ to $np^6$.

The p-block spans Groups 13 to 18 of the periodic table, defined as the groups in which the differentiating electron enters a $p$-orbital of the valence shell. The general valence configuration begins at $ns^2np^1$ for Group 13 (boron family) and increases by exactly one $p$-electron per group: Group 14 (carbon family) is $ns^2np^2$, Group 15 is $ns^2np^3$, Group 16 is $ns^2np^4$, Group 17 (halogens) is $ns^2np^5$, and Group 18 (noble gases, apart from helium) is $ns^2np^6$, a complete octet. For this chapter's two groups specifically: boron, $[\text{He}]2s^22p^1$, and its congeners aluminium, gallium, indium and thallium, all terminate their outer shell at $ns^2np^1$; carbon, $[\text{He}]2s^22p^2$, and its congeners silicon, germanium, tin and lead, all terminate at $ns^2np^2$. In every case it is the $p$ sub-shell of the outermost (valence) shell that is being filled one electron at a time as one moves left to right across the p-block, while the underlying $ns^2$ pair (and all inner shells) stays complete and is generally not involved in ordinary bonding, except where it is drawn into bonding at the top of the block or held back as an inert pair at the bottom, as later sections discuss. [!ANSWER] Group 13's outer configuration is $ns^2np^1$ and Group 14's is $ns^2np^2$, part of the general p-block pattern in which the $p$ sub-shell fills from $np^1$ at Group 13 through to the complete octet $np^6$ at Group 18.

Recall that the p-block is defined by the differentiating electron entering the outer p sub-shell, and that the p-electron count simply equals the group number minus 10; write out the specific configurations for Groups 13 and 14 using this rule.

Forgetting to include the outer $ns^2$ pair alongside the $np$ electrons when writing the configuration; confusing group number with the number of p-electrons directly rather than subtracting 10.