sodium atom

$Na.$

Octet Rule

$1s^{2}2s^{2}2p^0$ubrace$(3s^1$ubrace$)$

$1$ electron in the outer shell

chlorine atom

:ci$.$

Octet Rule

$1s^{2}2s^{2}2p^6$ubrace$(3s^{2}3p^5$ubrace${)}_7$

$7$ electrons in the outer shell

sodium cation

$N{a}^{+}$

$1s^2$ubrace$(2s^{2}2p^6$ubrace${)}_{8\text{e}\text{l}\text{e}}$

chloride anion

:$$i:$-$

$1s^{2}2s^{2}2p^6$ubrace$(3s^{2}3p^6$ubrace${)}_{8el}$

NaCl

$N{a}^{+}$

$C{l}^{-}$

$11$ protons

$17$ protons

$10$ electrons

$18$ electrons

sodium

chloride

cation

anion

$+1$ charge

$-1$ charge

zero overall charge

$4.$ Balancing charges: Suppose that $x$ represents an arbitrary cation and that $Y$ represents an anionic species. Using the charges indicate in the superscript of $x$ and $Y,$ fill in the remaining spaces below by writing the appropriate subscript for each $x$ and $Y$ species to balance the net charge on the ionic $x_a{Y}_b$ compound formed $($where a and $b$ represent whole numbers of $x$ and $Y,$ respectively$)$:

$\backslash$table$[[,Y^{-},Y^{2-},Y^{3-}$