Passage VI
An atomic orbital can contain 0, 1, or 2 electrons. It is filled when it contains 2 electrons. An orbital's location and shape are determined by its energy level and sublevel. Table 1 lists the first 4 energy levels, their sublevels, and the number of orbitals in each sublevel.
Table 2 names each of the sublevels in the first 4 energy levels.
Table 3 shows the order in which the sublevels are filled with electrons. Each sublevel must be filled before an electron can be added to the next sublevel.
Tables 4 illustrates a notation used to indicate the number of electrons per sublevel.
Tables adapted from Kenneth W. Whitten and Kenneth D. Gailey, General Chemistry. ©1981 by Saunders College Publishing.
31. If an atom in its ground state has 15 electrons, how many electrons are in the 3p sublevel?
Your Answer is
Correct Answer is C
Explanation
From table 4, it can be seen that there are at most 2 electrons on 1s, at most two electrons on 2s, at most 6 electrons on 2p, and at most 2 electrons on 3s, then 2+2+6+2=12 , so when an atom has a total of 15 electrons, the 3p sublevel should reach 15-12=3 electrons