Difference between revisions of "Mercury"

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{{Infobox element
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'''Mercury''' (also known as '''quicksilver''') is a chemical element with the symbol Hg (from its latin name '''hydrargyrum''', meaning silver water) and atomic number 80. It is the only liquid metal at room temperature.
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<!-- top -->
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|image name=Liquid Mercury by Bionerd from Wikipedia.jpg
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|image alt=
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|image size=
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|image name comment=Liquid mercury being poured in a glass, displaying high surface tension.
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|image name 2=
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|image alt 2=
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|image size 2=
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|image name 2 comment=
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<!-- General properties -->
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|name=Mercury
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|symbol=Hg
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|pronounce=
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|pronounce ref=
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|pronounce comment=
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|pronounce 2=
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|alt name=Hydrargyrum (Latin)<br>
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|alt names=Quicksilver
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|allotropes=
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|appearance=Shiny silvery dense liquid
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<!-- Periodic table -->
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|above=[[Cadmium|Cd]]
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|below=Cp
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|left=[[Gold]]
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|right=[[Thallium]]
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|number=80
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|atomic mass=200.592(3)
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|atomic mass 2=
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|atomic mass ref=
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|atomic mass comment=
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|series=
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|series ref=
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|series comment=
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|series color=
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|group=12
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|group ref=
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|group comment=
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|period=6
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|period ref=
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|period comment=
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|block=d
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|block ref=
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|block comment=
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|electron configuration= [Xe] 4f<sup>14</sup> 5d<sup>10</sup> 6s<sup>2</sup>
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|electron configuration ref=
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|electron configuration comment=
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|electrons per shell=2, 8, 18, 32, 18, 2
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|electrons per shell ref=
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|electrons per shell comment=
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<!-- Physical properties -->
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|physical properties comment=
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|color=Silvery
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|phase=Liquid
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|phase ref=
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|phase comment=
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|melting point K=234.321
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|melting point C=−38.829
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|melting point F=−37.8922
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|melting point ref=
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|melting point comment=
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|boiling point K=629.88
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|boiling point C=356.73
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|boiling point F=674.11
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|boiling point ref=
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|boiling point comment=
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|sublimation point K=
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|sublimation point C=
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|sublimation point F=
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|sublimation point ref=
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|sublimation point comment=
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|density gplstp=
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|density gplstp ref=
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|density gplstp comment=
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|density gpcm3nrt=13.534
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|density gpcm3nrt ref=
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|density gpcm3nrt comment=
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|density gpcm3nrt 2=
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|density gpcm3nrt 2 ref=
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|density gpcm3nrt 2 comment=
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|density gpcm3nrt 3=
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|density gpcm3nrt 3 ref=
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|density gpcm3nrt 3 comment=
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|density gpcm3mp=10.66
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|density gpcm3mp ref=
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|density gpcm3mp comment=
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|density gpcm3bp=
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|density gpcm3bp ref=
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|density gpcm3bp comment=
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|molar volume=
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|molar volume unit =
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|molar volume ref=
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|molar volume comment=
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|triple point K=234.3156
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|triple point kPa=1.65×10<sup>−7</sup>
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|triple point ref=
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|triple point comment=
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|triple point K 2=
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|triple point kPa 2=
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|triple point 2 ref=
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|triple point 2 comment=
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|critical point K=1750
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|critical point MPa=172
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|critical point ref=
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|critical point comment=
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|heat fusion=2.29
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|heat fusion ref=
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|heat fusion comment=
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|heat fusion 2=
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|heat fusion 2 ref=
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|heat fusion 2 comment=
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|heat vaporization=59.11
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|heat vaporization ref=
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|heat vaporization comment=
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|heat capacity=27.983
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|heat capacity ref=
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|heat capacity comment=
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|heat capacity 2=
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|heat capacity 2 ref=
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|heat capacity 2 comment=
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|vapor pressure 1=315
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|vapor pressure 10=350
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|vapor pressure 100=393
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|vapor pressure 1 k=449
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|vapor pressure 10 k=523
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|vapor pressure 100 k=629
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|vapor pressure ref=
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|vapor pressure comment=
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|vapor pressure 1 2=
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|vapor pressure 10 2=
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|vapor pressure 100 2=
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|vapor pressure 1 k 2=
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|vapor pressure 10 k 2=
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|vapor pressure 100 k 2=
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|vapor pressure 2 ref=
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|vapor pressure 2 comment=
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<!-- Atomic properties -->
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|atomic properties comment=
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|oxidation states=+4, +2, +1, −2
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|oxidation states ref=
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|oxidation states comment=(+1 and +2 are most common)
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|electronegativity=2.00
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|electronegativity ref=
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|electronegativity comment=
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|ionization energy 1=1007.1
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|ionization energy 1 ref=
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|ionization energy 1 comment=
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|ionization energy 2=1810
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|ionization energy 2 ref=
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|ionization energy 2 comment=
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|ionization energy 3=3300
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|ionization energy 3 ref=
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|ionization energy 3 comment=
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|number of ionization energies=
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|ionization energy ref=
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|ionization energy comment=
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|atomic radius=151
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|atomic radius ref=
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|atomic radius comment=
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|atomic radius calculated=
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|atomic radius calculated ref=
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|atomic radius calculated comment=
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|covalent radius=132±5
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|covalent radius ref=
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|covalent radius comment=
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|Van der Waals radius=155
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|Van der Waals radius ref=
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|Van der Waals radius comment=
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<!-- Miscellanea -->
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|crystal structure=rhombohedral
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|crystal structure prefix=
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|crystal structure ref=
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|crystal structure comment=
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|crystal structure 2=
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|crystal structure 2 prefix=
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|crystal structure 2 ref=
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|crystal structure 2 comment=
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|speed of sound=1451.4
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|speed of sound ref=
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|speed of sound comment=(liquid, at 20 °C)
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|speed of sound rod at 20=
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|speed of sound rod at 20 ref=
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|speed of sound rod at 20 comment=
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|speed of sound rod at r.t.=
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|speed of sound rod at r.t. ref=
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|speed of sound rod at r.t. comment=
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|thermal expansion=
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|thermal expansion ref=
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|thermal expansion comment=
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|thermal expansion at 25=60.4
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|thermal expansion at 25 ref=
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|thermal expansion at 25 comment=
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|thermal conductivity=8.30
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|thermal conductivity ref=
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|thermal conductivity comment=
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|thermal conductivity 2=
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|thermal conductivity 2 ref=
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|thermal conductivity 2 comment=
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|thermal diffusivity=
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|thermal diffusivity ref=
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|thermal diffusivity comment=
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|electrical resistivity=961
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|electrical resistivity unit prefix=n
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|electrical resistivity ref=
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|electrical resistivity comment=(at 25 °C)
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|electrical resistivity at 0=
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|electrical resistivity at 0 ref=
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|electrical resistivity at 0 comment=
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|electrical resistivity at 20=
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|electrical resistivity at 20 ref=
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|electrical resistivity at 20 comment=
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|band gap=
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|band gap ref=
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|band gap comment=
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|Curie point K=
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|Curie point ref=
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|Curie point comment=
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|magnetic ordering=diamagnetic
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|magnetic ordering ref=
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|magnetic ordering comment=
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|tensile strength=
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|tensile strength ref=
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|tensile strength comment=
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|Young's modulus=
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|Young's modulus ref=
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|Young's modulus comment=
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|Shear modulus=
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|Shear modulus ref=
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|Shear modulus comment=
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|Bulk modulus=
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|Bulk modulus ref=
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|Bulk modulus comment=
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|Poisson ratio=
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|Poisson ratio ref=
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|Poisson ratio comment=
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|Mohs hardness=
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|Mohs hardness ref=
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|Mohs hardness comment=
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|Mohs hardness 2=
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|Mohs hardness 2 ref=
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|Mohs hardness 2 comment=
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|Vickers hardness=
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|Vickers hardness ref=
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|Vickers hardness comment=
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|Brinell hardness=
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|Brinell hardness ref=
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|Brinell hardness comment=
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|CAS number=7439-97-6
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|CAS number ref=
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|CAS number comment=
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<!-- History -->
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|naming=
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|predicted by=
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|prediction date ref=
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|prediction date=
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|discovered by=Ancient Chinese and Indians (before 2000 BCE)
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|discovery date ref=
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|discovery date=
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|first isolation by=
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|first isolation date ref=
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|first isolation date=
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|discovery and first isolation by=
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|named by=
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|named date ref=
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|named date=
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|history comment label=
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|history comment=
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<!-- Isotopes -->
 +
|isotopes=
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|isotopes comment=
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|engvar=
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}}
 +
'''Mercury''' (also known as '''quicksilver''') is a chemical element with the symbol '''Hg''' (from its latin name '''hydrargyrum''', meaning ''silver water'') and atomic number 80. It is the only liquid metal at room temperature.
  
 
==Properties==
 
==Properties==
 
===Chemical===
 
===Chemical===
−
Mercury is resistant to most acids, although oxidizing acids, such as concentrated [[sulfuric acid]], [[nitric acid]] or [[aqua regia]] dissolve it to give its respective sulfate, nitrate, and chloride salts. Mercury has two potential oxidation states (I) and (II).  [[Mercury(I) nitrate]], or mercurous nitrate, can be prepared by dissolving mercury in cold dilute nitric acid, while [[mercury(II) nitrate]], mercuric nitrate, can be prepared by dissolving the metal in hot concentrated nitric acid. Like [[silver]], mercury reacts with atmospheric [[hydrogen sulfide]], but unlike silver will also react with solid [[sulfur]], forming [[mercury sulfide]] (cinnabar). Elemental sulfur is used to absorb mercury spills and vapors. Mercury will also form amalgams with [[gold]], [[aluminium]] or alkali metals.
+
Mercury is resistant to most acids, although oxidizing acids, such as concentrated [[sulfuric acid]], [[nitric acid]] or [[aqua regia]] dissolve it to give its respective sulfate, nitrate, and chloride salts. Mercury has two potential oxidation states (I) and (II).  [[Mercury(I) nitrate]], or mercurous nitrate, can be prepared by dissolving mercury in cold dilute nitric acid, while [[mercury(II) nitrate]], mercuric nitrate, can be prepared by dissolving the metal in hot concentrated nitric acid. Like [[silver]], mercury reacts with atmospheric [[hydrogen sulfide]], but unlike silver will also react with solid [[sulfur]], forming [[mercury sulfide]] (cinnabar). Elemental sulfur is used to absorb mercury spills and vapors. Mercury will also form amalgams with many metals such as [[gold]], [[aluminium]] or alkali metals, but will not dissolve [[iron]], [[platinum]], [[tantalum]] and [[tungsten]]. Lead-mercury amalgam has the interesting property of being permeable to liquid mercury, but not to other liquids, like water or solvents.<ref>https://www.youtube.com/watch?v=2JW8YGTdTjA</ref>
  
 
===Physical===
 
===Physical===
−
Mercury is a dense, silvery-white liquid metal. It is a poor conductor of heat, but a fair conductor of electricity. Mercury melts at −38.83 °C and boils at 356.73 °C. Unlike most metals that melt at low temperatures, liquid mercury in does not wet glass.
+
Mercury is a dense, silvery-white liquid metal. It is a poor conductor of heat, but a fair conductor of electricity. Mercury melts at −38.83 °C and boils at 356.73 °C. Unlike most metals that melt at low temperatures, liquid mercury does not wet glass. This property allows him to be easily cleaned from insoluble impurities and being easier to remove if it's spilled on a surface.
  
 
==Availability==
 
==Availability==
 
Mercury can be found in medical mercury thermometers. The packaging of these thermometers comes with a warning, that the product contains mercury and is dangerous for the environment. Old blood pressure meters also contain mercury. Other old devices that contain mercury are: old tilt switches, mercury electrodes, mercury manometers, mercury batteries, etc. Old amalgam fillings contain mercury. Some light sources, such as fluorescent lamps contain a minute amount of mercury, albeit too small to be of any importance.
 
Mercury can be found in medical mercury thermometers. The packaging of these thermometers comes with a warning, that the product contains mercury and is dangerous for the environment. Old blood pressure meters also contain mercury. Other old devices that contain mercury are: old tilt switches, mercury electrodes, mercury manometers, mercury batteries, etc. Old amalgam fillings contain mercury. Some light sources, such as fluorescent lamps contain a minute amount of mercury, albeit too small to be of any importance.
  
−
In EU the sale of mercury is restricted.
+
In EU the sale of mercury and its compounds is restricted.
  
 
Norway enacted a total ban on the use of mercury in the manufacturing and import/export of mercury products, in 2008.
 
Norway enacted a total ban on the use of mercury in the manufacturing and import/export of mercury products, in 2008.
  
−
==Preparation==
+
==Isolation==
−
Mercury can be prepared by reducing its salt with a reducing metal (though it's best avoiding metals that form amalgam).
+
Mercury can be prepared by reducing its salt with a reducing metal, such aluminium, in an aqueous solution. The aqueous solution also has the advantage of destroying any Hg-Al amalgam. However, a better choice would be to use [[copper]]. If you use iron, you'll end up with "powdered" mercury, basically mercury mixed with iron impurities, and it's not very easy to purify it. While you can add a non-oxidizing acid or a base to remove the impurities and coalesce the mercury, a better method involves adding metallic copper, which will absorb the mercury droplets, which means that you're better off just using copper in the first place.
  
 
A more dangerous method involves roasting cinnabar in a current of air and condensing the resulting mercury vapor. This method is extremely dangerous, as it generate highly toxic mercury vapors.
 
A more dangerous method involves roasting cinnabar in a current of air and condensing the resulting mercury vapor. This method is extremely dangerous, as it generate highly toxic mercury vapors.
 +
 +
"Dirty" mercury can be purified by squeezing it through a cloth or through a cotton in a syringe, and collecting the spills in a glass container. This works because mercury does not wet organic materials.
  
 
==Projects==
 
==Projects==
 
The use of mercury and mercury compounds in experiments carries a high risk of poisoning, mainly due to its vapors and the volatility of some of its compounds. The biggest risk however, is due to the low LD<sub>50</sub> of most of its compounds, their ability to be absorbed through the skin and long delay between poisoning and first symptoms. Any experiments must be performed either outside, in a fume hood or, if possible in a glovebox.
 
The use of mercury and mercury compounds in experiments carries a high risk of poisoning, mainly due to its vapors and the volatility of some of its compounds. The biggest risk however, is due to the low LD<sub>50</sub> of most of its compounds, their ability to be absorbed through the skin and long delay between poisoning and first symptoms. Any experiments must be performed either outside, in a fume hood or, if possible in a glovebox.
−
*Pharaoh's snake (thermal decomposition of [[mercury(II) thiocyanate]])
+
*[[Pharaoh's serpent]] (thermal decomposition of [[mercury(II) thiocyanate]])
 
*Castner–Kellner process
 
*Castner–Kellner process
 
*Make amalgams
 
*Make amalgams
−
*Mercury(II) nitrate synthesis
+
*[[Mercury(II) nitrate]] synthesis
−
*Mercury(II) chloride synthesis
+
*[[Mercury(II) chloride]] synthesis
−
*[[Mercury fulminate]] synthesis
+
*[[Mercury(II) fulminate]] synthesis
 +
*Demonstration of mercury's high density, by floating dense items on it
  
 
==Handling==
 
==Handling==
Line 40: Line 314:
  
 
===Disposal===
 
===Disposal===
−
Mercury spillings can be removed by adding a mixture of powdered elemental sulfur and zinc. The resulting solid must be taken to special disposal centers.  
+
Mercury spills can be removed by adding a mixture of powdered elemental [[sulfur]] and [[zinc]]. The resulting solid must be then taken to special disposal centers.  
  
 
==References==
 
==References==
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*[http://www.sciencemadness.org/talk/viewthread.php?tid=46124 Mercury Oxidation - Prevention]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=46124 Mercury Oxidation - Prevention]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=18162 Refining mercury from cinnabar]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=18162 Refining mercury from cinnabar]
 +
*[http://www.sciencemadness.org/talk/viewthread.php?tid=131436 Elemental Mercury from cinnabar]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=15853 How should I clean my mercury?]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=15853 How should I clean my mercury?]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=16917 mercury from broken thermometer]
 
*[http://www.sciencemadness.org/talk/viewthread.php?tid=16917 mercury from broken thermometer]
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[[Category:Metals]]
 
[[Category:Metals]]
 
[[Category:Transition metals]]
 
[[Category:Transition metals]]
 +
[[Category:Post-transition metals]]
 
[[Category:D-block]]
 
[[Category:D-block]]
 
[[Category:Heavy metal toxicants]]
 
[[Category:Heavy metal toxicants]]
 +
[[Category:Liquids]]
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[[Category:Minerals]]
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[[Category:Volatile metals]]
 +
[[Category:Neurotoxins]]

Latest revision as of 00:11, 11 December 2019

Mercury,  80Hg
Liquid Mercury by Bionerd from Wikipedia.jpg
Liquid mercury being poured in a glass, displaying high surface tension.
General properties
Name, symbol Mercury, Hg
Alternative names Hydrargyrum (Latin)
Quicksilver
Appearance Shiny silvery dense liquid
Mercury in the periodic table
Cd
↑
Hg
↓
Cp
Gold ← Mercury → Thallium
Atomic number 80
Standard atomic weight (Ar) 200.592(3)
Group, block , d-block
Period period 6
Electron configuration [Xe] 4f14 5d10 6s2
per shell
 2, 8, 18, 32, 18, 2
Physical properties
Silvery
Phase Liquid
Melting point 234.321 K ​(−38.829 °C, ​−37.8922 °F)
Boiling point 629.88 K ​(356.73 °C, ​674.11 °F)
Density near r.t. 13.534 g/cm3
when liquid, at  10.66 g/cm3
Triple point 234.3156 K, ​1.65×10−7 kPa
Critical point 1750 K, 172 MPa
Heat of fusion 2.29 kJ/mol
Heat of 59.11 kJ/mol
Molar heat capacity 27.983 J/(mol·K)
 pressure
Atomic properties
Oxidation states +4, +2, +1, −2 ​(+1 and +2 are most common)
Electronegativity Pauling scale: 2.00
energies 1st: 1007.1 kJ/mol
2nd: 1810 kJ/mol
3rd: 3300 kJ/mol
Atomic radius empirical: 151 pm
Covalent radius 132±5 pm
Van der Waals radius 155 pm
Miscellanea
Crystal structure ​
Speed of sound 1451.4 m/s (liquid, at 20 °C)
Thermal expansion 60.4 µm/(m·K) (at 25 °C)
Thermal conductivity 8.30 W/(m·K)
Electrical resistivity 961 nΩ·m (at 25 °C)
Magnetic ordering diamagnetic
CAS Registry Number 7439-97-6
History
Discovery Ancient Chinese and Indians (before 2000 BCE)
· references

Mercury (also known as quicksilver) is a chemical element with the symbol Hg (from its latin name hydrargyrum, meaning silver water) and atomic number 80. It is the only liquid metal at room temperature.

Properties

Chemical

Mercury is resistant to most acids, although oxidizing acids, such as concentrated sulfuric acid, nitric acid or aqua regia dissolve it to give its respective sulfate, nitrate, and chloride salts. Mercury has two potential oxidation states (I) and (II). Mercury(I) nitrate, or mercurous nitrate, can be prepared by dissolving mercury in cold dilute nitric acid, while mercury(II) nitrate, mercuric nitrate, can be prepared by dissolving the metal in hot concentrated nitric acid. Like silver, mercury reacts with atmospheric hydrogen sulfide, but unlike silver will also react with solid sulfur, forming mercury sulfide (cinnabar). Elemental sulfur is used to absorb mercury spills and vapors. Mercury will also form amalgams with many metals such as gold, aluminium or alkali metals, but will not dissolve iron, platinum, tantalum and tungsten. Lead-mercury amalgam has the interesting property of being permeable to liquid mercury, but not to other liquids, like water or solvents.[1]

Physical

Mercury is a dense, silvery-white liquid metal. It is a poor conductor of heat, but a fair conductor of electricity. Mercury melts at −38.83 °C and boils at 356.73 °C. Unlike most metals that melt at low temperatures, liquid mercury does not wet glass. This property allows him to be easily cleaned from insoluble impurities and being easier to remove if it's spilled on a surface.

Availability

Mercury can be found in medical mercury thermometers. The packaging of these thermometers comes with a warning, that the product contains mercury and is dangerous for the environment. Old blood pressure meters also contain mercury. Other old devices that contain mercury are: old tilt switches, mercury electrodes, mercury manometers, mercury batteries, etc. Old amalgam fillings contain mercury. Some light sources, such as fluorescent lamps contain a minute amount of mercury, albeit too small to be of any importance.

In EU the sale of mercury and its compounds is restricted.

Norway enacted a total ban on the use of mercury in the manufacturing and import/export of mercury products, in 2008.

Isolation

Mercury can be prepared by reducing its salt with a reducing metal, such aluminium, in an aqueous solution. The aqueous solution also has the advantage of destroying any Hg-Al amalgam. However, a better choice would be to use copper. If you use iron, you'll end up with "powdered" mercury, basically mercury mixed with iron impurities, and it's not very easy to purify it. While you can add a non-oxidizing acid or a base to remove the impurities and coalesce the mercury, a better method involves adding metallic copper, which will absorb the mercury droplets, which means that you're better off just using copper in the first place.

A more dangerous method involves roasting cinnabar in a current of air and condensing the resulting mercury vapor. This method is extremely dangerous, as it generate highly toxic mercury vapors.

"Dirty" mercury can be purified by squeezing it through a cloth or through a cotton in a syringe, and collecting the spills in a glass container. This works because mercury does not wet organic materials.

Projects

The use of mercury and mercury compounds in experiments carries a high risk of poisoning, mainly due to its vapors and the volatility of some of its compounds. The biggest risk however, is due to the low LD50 of most of its compounds, their ability to be absorbed through the skin and long delay between poisoning and first symptoms. Any experiments must be performed either outside, in a fume hood or, if possible in a glovebox.

Handling

Safety

Elemental mercury in its liquid form is not very reactive, but its vapors and compounds are extremely toxic. Mercury ions have a long half life in the body, and are potent cumulative toxins. If the metal is dropped onto a porous surface, such as wood, the metal can split into micron-sized beads which will evaporate and fill the room with extremely toxic mercury vapor. Many compounds can rapidly absorb through the skin and cause severe mercury poisoning. This leads to severe medical problems and can eventually lead to death, usually after a longer period of time.

Storage

Mercury should be stored in closed glass or thick plastic bottles, in a special hazardous substance cabinet, with a proper label. A bed of elemental sulfur can also be used, to absorb the leaking mercury vapors.

Mercury compounds should be stored in a similar way.

Disposal

Mercury spills can be removed by adding a mixture of powdered elemental sulfur and zinc. The resulting solid must be then taken to special disposal centers.

References

  1. ↑ https://www.youtube.com/watch?v=2JW8YGTdTjA

Relevant Sciencemadness threads

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