Question

na3po4 is named as
a sodium phosphide
b sodium(iii) phosphate
c sodium phosphite
d sodium phosphate

Explanation:

$Na_3PO_4$ is an ionic compound. Sodium ($Na^+$) is the cation and the poly - atomic anion is phosphate ($PO_4^{3 -}$). The name of the compound is based on the cation followed by the anion name. Sodium has a fixed +1 charge so no Roman numeral is needed. Phosphide is $P^{3 -}$, phosphite is $PO_3^{3 -}$, and the correct name for $Na_3PO_4$ is sodium phosphate.

Answer:

D. sodium phosphate