Question

Zinc phosphide, `Zn_3P_2`, is often used as a rat poison. Phosphorus has 5 valence electrons. How many valence electrons does each zinc atom lose?

Answer 1

The phosphide anion is formally `P^(3-)`..........

Explanation:

And the zinc cation is `Zn^(2+)`. When the ions form a salt, clearly they form an electrically neutral species; and thus the formulation of the salt is `Zn_3P_2`. Each phosphorus atom formally possesses 8 valence electrons. The `4s^2` valence electrons on zinc are presumed to be ABSENT, and this centre is a `d^10` dication.