The oxidation state or oxidation number of an atom within a compound provides insight into the electron distribution in that molecule. An oxidation state is a hypothetical charge that an atom would have if all its bonds were purely ionic. While calculating the oxidation state, some rules should be followed:
- For an atom in its elemental form, the oxidation number is always zero.
- For a simple monoatomic ion, the oxidation number equals the ion's charge.
- In compounds, hydrogen typically has an oxidation number of +1, and oxygen has -2, except in peroxides where it is -1.
- The algebraic sum of oxidation numbers for all atoms in a molecule or polyatomic ion equals the charge on the molecule or ion.
Applied to our exercise, considering the oxidation number of X is +2, Y is +5 and Z is -2, we can calculate the oxidation states and verify if the sum equals zero as it should in a compound that adheres to the rule of chemical neutrality. This systematic approach allows us to determine the correct stoichiometry of the compound by evaluating each given option, ensuring the oxidation states balance out.