Here's why:

* Cr represents the element chromium.

* O represents the element oxygen.

* The subscript 2 after Cr indicates that there are two chromium atoms in the compound.

* The subscript 3 after O indicates that there are three oxygen atoms in the compound.

* Chromium can have multiple oxidation states (charges). In this compound, chromium has a +3 charge, which is why it is written as Chromium(III).

Therefore, the complete name of the compound is Chromium(III) oxide.