Question

match the atom to the electron configuration.
chlorine, cl
neon, ne
sodium, na
1s² 2s² 2p⁶ 3s¹
1s² 2s² 2p⁶
1s² 2s² 2p⁶ 3s² 3p⁵

Explanation:

Step1: Determine the atomic number of each element

• Chlorine (\(Cl\)) has an atomic number of \(17\).
• Neon (\(Ne\)) has an atomic number of \(10\).
• Sodium (\(Na\)) has an atomic number of \(11\).

Step2: Write the electron configuration for each element

• For \(Cl\) (\(Z = 17\)):
• Fill the orbitals in the order \(1s, 2s, 2p, 3s, 3p\).
• \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{5}\)
• For \(Ne\) (\(Z = 10\)):
• \(1s^{2}2s^{2}2p^{6}\)
• For \(Na\) (\(Z = 11\)):
• After filling \(1s^{2}2s^{2}2p^{6}\) (which accounts for \(10\) electrons), the \(11^{th}\) electron goes into the \(3s\) orbital. So the electron configuration is \(1s^{2}2s^{2}2p^{6}3s^{1}\)

Answer:

• \(1s^{2}2s^{2}2p^{6}3s^{1}\) → Sodium, \(Na\)
• \(1s^{2}2s^{2}2p^{6}\) → Neon, \(Ne\)
• \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{5}\) → Chlorine, \(Cl\)