Final answer:
The second energy level of an atom can hold a maximum of eight electrons, with the 2s subshell holding two and the 2p subshell holding six.
Step-by-step explanation:
The second energy level in an atom can hold a maximum of eight electrons. This capacity is determined by the number of orbitals available at this level. Since each orbital can contain two electrons, and the second energy level has four orbitals (one 2s and three 2p orbitals), a total of eight electrons can be accommodated. The 2s subshell can hold a maximum of two electrons, while the 2p subshell can hold a maximum of six electrons. It's important to note that these subshells fill with electrons according to the Pauli exclusion principle and Hund's rule, which state that each orbital is filled with one electron before any is paired, and each paired electron must have an opposite spin.