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Chem Studio by Learn4Less

Element 17

Chlorine (Cl)

17
Cl

chlorine

Nonmetal · p block · group 17, period 3

Electron configuration
[Ne] 3s2 3p5[\mathrm{Ne}]\,3s^{2}\,3p^{5}
Unpaired electrons
1 (paramagnetic)
Valence electrons
7
Molar mass
35.45 g/mol
Electronegativity
3.16
Atomic radius
99 pm
First ionization energy
1251 kJ/mol
Next ionization energies
2,298, 3,822, 5,159
Electron affinity
349 kJ/mol released

Practice

Practice chlorine

Questions from the course about chlorine. If you’re signed in, your answers count toward your progress.

  1. Question 1Ground-state electron configurationWarm-up

    Which is the ground-state electron configuration of a neutral chlorine atom (Cl\ce{Cl})?

  2. Question 2Electron configuration of an ionWarm-up

    Which is the ground-state electron configuration of ClX−\ce{Cl-}?

  3. Question 3Estimate the effective nuclear chargeWarm-up

    Use the simple shielding model Zeff=Z−SZ_{\text{eff}} = Z - S, where SS is the number of core (inner-shell, n<3n < 3) electrons and electrons in the same shell do not shield each other. What is ZeffZ_{\text{eff}} for a valence electron of chlorine (Cl\ce{Cl})?

    Whole number.