- (D) Phosphorous has 15 electrons. In its ground state, the lowest energy
sublevels will be occupied. For phosphorous, the first 12 electrons fill the
1 s, 2s, 2 p, and 3s orbitals, respectively. The remaining 3 electrons occupy
each of the subsequent 3p orbitals (of which there are 3) with 1 electron
each (with similar spins) due to Hund’s Rule. Because 6 electrons are
possible in the 3p sublevel, it is considered to be half-filled.
marvins-underground-k-12
(Marvins-Underground-K-12)
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