Helium,[1] He abbreviatione, est elementum chemicum. Maxima cryogenica elementis omnibus est, et propter energia puncti zerois gas nobile puncto triplice caret, solidificatio sua super pressionem atmosphaericam quaeret. Et liquidum Helii isotopi sub zero absoluto pro superfluditate usum est.

2 hydrogeniumheliumlithium


He

Ne
Proprietates generales
Nomen, Symbolus, Numerus Atomicus helium, He, 2
Grex, Periodus, Glaeba 18, 1, s
Color
transparens
Pondus atomicum 4,002602(2)  g·mol−1
e- per sphaeram 2
Proprietates physicae
Status Gas
Punctum liquefactionis 0,95 K (26 atm)
Punctum fervoris 4,22 K
(-268,93 °C, -452,07 °F)
Punctum triplex Nullum
Punctum criticum 5,19 K, 0,227 MPa
Calor latens fusionis 0,0138 kJ·mol−1
Capacitas caloris (25 °C) 20,786 J·mol−1·K−1
Proprietates atomicae
Structura crystallina Hexagona
Affectus oxidationis 0
Radius covalentiae 28  pm
Radius Van der Waals 140 pm
Varietas
Conductus caloris (25 °C) 0,1513  W/(m·K)
Velocitas soni (25 °C) 972 m/s
Helium
  1. "Helium": Peter van der Krogt, "Elementa chemica" apud situm Elementymology & Elements Multidict

Nexus externi

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Elementa chemica: series paginarum brevium

1 H 2 He 3 Li 4 Be 5 B 6 C 7 N 8 O 9 F 10 Ne 11 Na 12 Mg 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 Mn 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 55 Cs 56 Ba 57 La 58 Ce 59 Pr 60 Nd 61 Pm 62 Sm 63 Eu 64 Gd 65 Tb 66 Dy 67 Ho 68 Er 69 Tm 70 Yb 71 Lu 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 87 Fr 88 Ra 89 Ac 90 Th 91 Pa 92 U 93 Np 94 Pu 95 Am 96 Cm 97 Bk 98 Cf 99 Es 100 Fm 101 Md 102 No 103 Lr 104 Rf 105 Db 106 Sg 107 Bh 108 Hs 109 Mt 110 Ds 111 Rg 112 Cn 113 Nh 114 Fl 115 Mc 116 Lv 117 Ts 118 Og