Holmium, 67 Ho Holmium Pronunciation (HOHL -mee-əm ) Appearance sillery white Standard atomic weight A r, std (Ho) 7002164930328000000♠ 164.930328 (7)[ 1] Holmium in the periodic cairt
Atomic nummer (Z ) 67 Group group n/a Period period 6 Block f-block Element category Lanthanide Electron confeeguration [Xe ] 4f11 6s2 Electrons per shell 2, 8, 18, 29, 8, 2 Pheesical properties Phase at STP solit Meltin pynt 1734 K (1461 °C, 2662 °F) Bylin pynt 2993 K (2720 °C, 4928 °F) Density (near r.t. ) 8.79 g/cm3 when liquid (at m.p. ) 8.34 g/cm3 Heat o fusion 17.0 kJ/mol Heat o vapourisation 265 kJ/mol Molar heat capacity 27.15 J/(mol·K) Vapour pressur
P (Pa)
1
10
100
1 k
10 k
100 k
at T (K)
1432
1584
(1775)
(2040)
(2410)
(2964)
Atomic properties Oxidation states 0,[ 2] +1, +2, +3 (a basic oxide) Electronegativity Pauling scale: 1.23 Atomic radius empirical: 176 pm Covalent radius 192±7 pm Colour lines in a spectral range Spectral lines o holmiumIther properties Naitural occurrence primordial Creestal structur hexagonal close-packed (hcp) Speed o soond thin rod 2760 m/s (at 20 °C) Thermal expansion (r.t. ) (poly) 11.2 µm/(m·K) Thermal conductivity 16.2 W/(m·K) Electrical resistivity (r.t. ) (poly) 814 n Ω·m Magnetic orderin paramagnetic Young's modulus 64.8 GPa Shear modulus 26.3 GPa Bulk modulus 40.2 GPa Poisson ratio 0.231 Vickers haurdness 481 MPa Brinell haurdness 746 MPa CAS Nummer 7440-60-0 History Diskivery Marc Delafontaine (1878) Main isotopes o holmium
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in
calc from C
diff
report
ref
C
1461
—
—
K
1734
1734
0
F
2662
2662
0
WD
1734 ! 1734 kelvin
input
C: 1461, K: 1734, F: 2662
comment
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in
calc from C
diff
report
ref
C
2720
—
—
K
2993
2990
3
delta
F
4928
4930
-2
delta
WD
2873 ! 2873 kelvin
input
C: 2720, K: 2993, F: 4928
comment
References
Thir references will appear in the airticle, but this list appears anerly on this page.
↑ Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)" . Pure and Applied Chemistry . 88 (3): 265–91. doi :10.1515/pac-2015-0305 .
↑ Yttrium and all lanthanides except Ce, Pm, Eu, Tm, Yb have been observed in the oxidation state 0 in bis(1,3,5-tri-t-butylbenzene) complexes, see Cloke, F. Geoffrey N. (1993). "Zero Oxidation State Compounds of Scandium, Yttrium, and the Lanthanides". Chem. Soc. Rev . 22 : 17–24. doi :10.1039/CS9932200017 .