Answer:
a. PbO.
Explanation:
- The formula unit of a stable chemical compound should maintain that the overall charge of the compound is zero (not charged).
- The formula unit of a compound is represented by the lowest ratio numbers of the ions forming the compound.
Choice a: is the right answer PbO
- That lead is divalent cation Pb²⁺ and O is considered as a divalent anion O²⁻.
- So, the formula unit contains Pb:O with a ratio of 1:1 (PbO)
Choice b: is a wrong choice Li₂B
- The lithium cation is a monovalent cation Li¹⁺ and boron is a trivalent cation B³⁺, so we can not do that.
Choice c: is a wrong choice Al₂Pb₃
- that Al is a trivalent cation Al³⁺ and Pb is a divalent cation Pb²⁺, so we can not do this for the two cations.
Choice d: is a wrong choice ClO
- that Cl may act as Cl¹⁺ and O acts as O²⁻, so the right formula unit should be Cl₂O.
