Question

1. practice: in the spaces below, write and illustrate electron configurations for the next four elements: nitrogen, oxygen, fluorine, and neon. when you are finished, use the gizmo to check your work. correct any improper configurations.

nitrogen configuration:________________________
oxygen configuration:________________________
fluorine configuration:________________________
neon configuration:________________________

1. apply: atoms are most stable when their outermost shell is full. if their outermost shell is not full, atoms tend to gain, lose, or share electrons until the shell fills up. while doing this, atoms react and form chemical bonds with other atoms.

based on this, what can you infer about the reactivity of helium and neon?________________________

Explanation:

Step1: Determine electron configurations

• Nitrogen: Nitrogen has 7 electrons. Using the Aufbau principle, electrons fill \(1s\) first (2 electrons), then \(2s\) (2 electrons), and then \(2p\) (3 electrons). So the electron configuration is \(1s^{2}2s^{2}2p^{3}\). In the orbital diagram: \(1s\) has 2 electrons (two - half - filled squares), \(2s\) has 2 electrons (two - half - filled squares), and \(2p\) has 3 electrons (three single - filled squares).
• Oxygen: Oxygen has 8 electrons. Electron configuration is \(1s^{2}2s^{2}2p^{4}\). Orbital diagram: \(1s\) (2 electrons), \(2s\) (2 electrons), \(2p\) (4 electrons: two single - filled and one double - filled square).
• Fluorine: Fluorine has 9 electrons. Electron configuration is \(1s^{2}2s^{2}2p^{5}\). Orbital diagram: \(1s\) (2 electrons), \(2s\) (2 electrons), \(2p\) (5 electrons: one single - filled and two double - filled squares).
• Neon: Neon has 10 electrons. Electron configuration is \(1s^{2}2s^{2}2p^{6}\). Orbital diagram: \(1s\) (2 electrons), \(2s\) (2 electrons), \(2p\) (6 electrons: three double - filled squares).

Step2: Analyze reactivity of helium and neon

• Helium has a full outer shell (\(1s^{2}\)) and neon has a full outer shell (\(2s^{2}2p^{6}\)). According to the rule that atoms are most stable when their outermost shell is full and tend to react when it is not, these elements do not need to gain, lose, or share electrons.

Answer:

• Nitrogen configuration: \(1s^{2}2s^{2}2p^{3}\) (Orbital diagram: \(1s\) - two electrons, \(2s\) - two electrons, \(2p\) - three single - electron squares)
• Oxygen configuration: \(1s^{2}2s^{2}2p^{4}\) (Orbital diagram: \(1s\) - two electrons, \(2s\) - two electrons, \(2p\) - two single and one double - electron square)
• Fluorine configuration: \(1s^{2}2s^{2}2p^{5}\) (Orbital diagram: \(1s\) - two electrons, \(2s\) - two electrons, \(2p\) - one single and two double - electron squares)
• Neon configuration: \(1s^{2}2s^{2}2p^{6}\) (Orbital diagram: \(1s\) - two electrons, \(2s\) - two electrons, \(2p\) - three double - electron squares)
• Helium and neon are unreactive (inert) because their outermost electron shells are full.