Phosphorus is an element. Elements are usually converted from moles to atoms using Alvogardo's number
Phosphorus can occur as an eight sided molecules. If the number of 3.44 moles is the number of
This gives the number of molecules of
It is important to note that normally the simple conversion of moles directly to atoms is the correct method.
Don't convert to molecules first unless directed to do so in the problem, as Phosphorus does not always occur in the molecular form as some elements like Hydrogen