How many electrons can the second shell of an atom hold?

The second shell of an atom can hold up to eight electrons. This is based on the rules of electron configuration and the structure of electron shells. Each electron shell can be described by the principal quantum number (n), and the second shell corresponds to (n = 2). The formula for calculating the maximum number of electrons in a shell is given by (2n^2).

Applying this formula for the second shell where (n = 2):

[

2(2^2) = 2(4) = 8

]

Thus, the second shell can accommodate a total of eight electrons. This allows for a stable electron configuration in various elements, hence supporting the octet rule often used in chemistry to explain the chemical behavior of atoms. The other answer choices do not accurately reflect the maximum capacity of the second shell; four, six, and two electrons do not adhere to the established principles of electron filling in atomic structure.