The 2s orbital in calcium is more stable (more negative energy) than the 2p orbital even though the 2p orbital has its maximum electron density closer to the nucleus. the reason for this higher stability is: a. calcium's valence orbitals have n = 4 b. the 1s orbital screens the 2p orbital more than the 2s orbital c. due to its greater penetration, the 2s orbital has more electron density close to the nucleus than the 2p orbital d. calcium is an exception to usual trends e. none of these