Question

What is the formula of the compound vanadium (V) oxide? Use the list of polyatomic ions and the periodic table to help you answer. A. VO2 B. VO5 C. V5O2 D. V2O5 E. V2O5

Answer 1

D.V2O5                                                                                                     Vanadium(V) oxide is the inorganic compound with the formula V2O5. Commonly known as vanadium pentoxide,                                                                                

Answer 2

Answer: D. $V_2O_5$

Explanation: Ionic compound is formed by transfer of electrons from metal to non metal.

For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.  

Here vanadium is having an oxidation state of +5 and oxide is a ion with oxidation state of -2. Thus on exchange of their oxidation states, they combine to form neutral $V_2O_5$.