Question

which statement best describes the arrangement of electrons in an atom of fluorine (f)? (1 point) there are five electrons in the first energy level and two electrons in the second energy level. there are two electrons in the first energy level and seven electrons in the second energy level. there are two electrons in the first energy level and five electrons in the second energy level. there are seven electrons in the first energy level and two electrons in the second energy level.

Explanation:

To determine the electron arrangement of fluorine (F), we first recall its atomic number, which is 9. This means a fluorine atom has 9 electrons. The electron - filling rule for energy levels is that the first energy level (\(n = 1\)) can hold a maximum of 2 electrons, and the second energy level (\(n=2\)) can hold a maximum of 8 electrons.

• For the first option: If there were 5 electrons in the first energy level, it would violate the maximum capacity of 2 electrons for the first energy level, so this option is incorrect.
• For the second option: The first energy level has 2 electrons (which is the maximum it can hold), and the remaining electrons \(9 - 2=7\) go into the second energy level. This follows the electron - filling rules.
• For the third option: If there were 5 electrons in the second energy level, the total number of electrons would be \(2 + 5=7\), which is less than the atomic number of fluorine (9), so this option is incorrect.
• For the fourth option: The first energy level can only hold a maximum of 2 electrons, so having 7 electrons in the first energy level is a violation of the electron - filling rules, and this option is incorrect.

Answer:

B. There are two electrons in the first energy level and seven electrons in the second energy level.