Question

question 14 (1 point)
which element has the electron configuration ar4s²?
sodium
calcium
phosphorus
argon

Explanation:

• Sodium (Na): Its electron configuration is \([Ne]3s^{1}\), not \([Ar]4s^{2}\).
• Calcium (Ca): Argon (\([Ar]\)) has 18 electrons. The \(4s^{2}\) adds 2 more electrons. So total electrons \(=18 + 2=20\). Calcium has an atomic number of 20, and its electron configuration is \([Ar]4s^{2}\).
• Phosphorus (P): Its electron configuration is \([Ne]3s^{2}3p^{3}\), not \([Ar]4s^{2}\).
• Argon (Ar): Its electron configuration is \([Ne]3s^{2}3p^{6}\), not \([Ar]4s^{2}\).

Answer:

calcium