(TXT) 20 Ca Calcium (plaintext)
       
        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 Hf Ta W  Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
        Fr Ra Ac Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
                                                             
              Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu      
              Th Pa U  Np Pu Am Cm Bk Cf Es Fm Md No Lr      
       
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       | 20   ____          |
       |     / ___|__ _     |
       |    | |   / _` |    |
       |    | |__| (_| |    |
       |     \____\__,_|    |
       |                    |
       |       Calcium      |
       |       40.08 u      |
       +--------------------+
       
 (TXT) Wiki Article:           Calcium
       Electron Configuration: [Ar]4s2
       Electronegativity:      1
       Atomic Radius:          231 pm
       Ionization Energy:      6.113 eV
       Electron Affinity:      
       Oxidation States:       2
       Standard State:         Solid
       Melting Point:          1115 K
       Boiling Point:          1757 K
       Density:                1.54 g/cm3
 (DIR) Family:                 Alkaline earth metal
       Year Discovered:        Ancient
       Number of Neutrons:     20
       Number of Protons:      20
       Number of Electrons:    20
       Number of Valence:      2
       Valency:                2
       Group:                  2
       Period:                 4
 (DIR) Shell:                  s-shell
       Specific Heat:          0.647 J/g K
       Radioactive:            0
       Occurrence:             Natural
 (DIR) Source:                 Dying high-mass stars
 (DIR) Source:                 White dwarf supernovae