Question

which electron configuration belongs to chlorine (cl)? 1s² 2s² 2p⁶ 3s² 3p⁵ 1s² 2s² 2p⁶ 3s² 3p⁶ 1s² 2s² 2p⁶ 3s² 3p⁷

Explanation:

Step1: Determine the atomic number of Chlorine

Chlorine has an atomic number of 17.

Step2: Calculate the total number of electrons in each configuration

• For 1s² 2s² 2p⁶ 3s² 3p⁵: \(2 + 2+6 + 2+5=17\)
• For 1s² 2s² 2p⁶ 3s² 3p⁶: \(2 + 2+6 + 2+6 = 18\)
• For 1s² 2s² 2p⁶ 3s² 3p⁷: \(2 + 2+6 + 2+7=19\)

Step3: Match with the atomic number

Since Chlorine has 17 electrons, the configuration \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{5}\) is correct.

Answer:

1s² 2s² 2p⁶ 3s² 3p⁵