17 - Chlorine diatomic nonmetal
Discovered by Carl Wilhelm Scheele in 1774
Chlorine is a chemical element with symbol Cl and atomic number 17. It also has a relative atomic mass of 35.5. Chlorine is in the halogen group (17) and is the second lightest halogen following fluorine.
H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
57-71 La-Lu Lanthanides
89-103 Ac-Lr Actinides
| Shell | Electrons | Orbitals |
|---|---|---|
| 1 | 2 | 2 in 1s |
| 2 | 8 | 2 in 2s + 6 in 2p |
| 3 | 7 | 2 in 3s + 5 in 3p |
35.5 u Atomic Mass
0.97 Å Atomic Radius
239 K Boiling Point
1.02 Å Covalent Radius
0.0032 g/cm³ Density
349 Electron Affinity
3.16 Electronegativity
13 eV First Ionization Energy
172 K Melting Point
3 Number of Shells
7 Electron Valency
17 Atomic Number
2, 8, 7 Electron Shell Occupations
0.479 J/(g K) Specific Heat