Final answer:
The chemical formula P2O5 contains 2 phosphorus atoms and 5 oxygen atoms, making option A) correct.
Step-by-step explanation:
The chemical formula P2O5 represents a molecule consisting of 2 phosphorus atoms and 5 oxygen atoms. Therefore, the correct answer is A) 2 phosphorus, 5 oxygen. In chemistry, the subscripts following the element symbols indicate the number of atoms of each element present in the molecule.
It is also important to note that P2O5 is often referred to as phosphorus pentoxide, which is a common name for this compound. This compound is part of a reaction where one mole of molecular phosphorus reacts with five moles of elemental oxygen to make one mole of tetraphosphorus decoxide, as seen in the balanced equation P4 (s) + 5O2 (g) → 2P2O5 (S).