Question

how many electrons will phosphorus need to gain or lose to be left with a full outer shell of valence electrons? * 2 points p gain 1 lose 2 gain 3 lose 4 gain 5 lose 6 gain 7 lose 8

Explanation:

Step1: Recall phosphorus electron - configuration

Phosphorus (P) has an atomic number of 15. Its electron - configuration is 1s²2s²2p⁶3s²3p³, and it has 5 valence electrons.

Step2: Determine octet rule need

To achieve a full outer shell (octet, 8 valence electrons), it needs to gain electrons. Since it has 5 valence electrons, 8 - 5=3. So it needs to gain 3 electrons.

Answer:

gain 3