State whether the following statement is true or false:
Sodium shows valency of $Na^+$ and $Na^{2+}$.

(FALSE) The statement is False.
Sodium $(Na)$ has an atomic number of $11$. Its electronic configuration is $2, 8, 1$. To achieve a stable octet,it loses one electron to form a sodium ion with a charge of $+1$ $(Na^+)$. It does not lose two electrons to form $Na^{2+}$ because the energy required to remove the second electron from the stable inner shell is extremely high.