Final answer:
The fourth shell (n=4) can hold a maximum of 32 electrons, as determined by the formula 2n².
Step-by-step explanation:
The principal quantum number n indicates the energy level or shell that an electron occupies. According to the formula 2n², which is used to calculate the maximum number of electrons that can fit in a shell, we can determine how many electrons the n=4 shell can hold.
For the first shell (n=1), as you mentioned, the calculation is 2(1)² = 2, showing that it can hold 2 electrons. For the second shell (n=2), it's 2(2)² = 8, meaning it can hold 8 electrons. Now applying this formula to the fourth shell (n=4), we perform 2(4)² = 2 × 16 = 32. Therefore, the answer to the question is 32 electrons for the n=4 shell.