Mendelevi (Md)

chemical element with the atomic number of 101 and symbol Md

Atomic Number	101
Atomic Weight	258
Rhif màs	244

Group
Period	7
Block	f

Proton	101 p⁺
Niwtron	143 n⁰
Electron	101 e^-

Nodwedd Ffisegol

Atomic Radius
molar volume
covalent radius	173 pm 139 pm
Metallic Radius
ionic radius	109.5 pm
Crystal Radius	123.5 pm
Van der Waals radius	246 pm 327.4 pm
density	10.3 g/cm³

Nodwedd Gemegol

egni

proton affinity
electron affinity
ionization energy	6.58 eV/particle 10 eV/particle 24.3 eV/particle 40 eV/particle 54.1 eV/particle 76 eV/particle 96 eV/particle 115.1 eV/particle 143.9 eV/particle 162 eV/particle 187 eV/particle 215 eV/particle 240 eV/particle 260 eV/particle 282 eV/particle 307 eV/particle 334 eV/particle 360 eV/particle 386 eV/particle 412 eV/particle 438 eV/particle 462 eV/particle 486 eV/particle 659 eV/particle 690 eV/particle 723 eV/particle 760 eV/particle 794 eV/particle 828 eV/particle 885 eV/particle 920 eV/particle 958 eV/particle 994 eV/particle 1,160 eV/particle 1,200 eV/particle 1,250 eV/particle 1,290 eV/particle 1,430 eV/particle 1,480 eV/particle 1,620 eV/particle 1,660 eV/particle 1,840 eV/particle 1,930 eV/particle 2,020 eV/particle 2,110 eV/particle 2,200 eV/particle 2,290 eV/particle 2,380 eV/particle 2,000 eV/particle 2,580 eV/particle 2,680 eV/particle 2,760 eV/particle 2,860 eV/particle 2,950 eV/particle 3,050 eV/particle 3,513 eV/particle 3,592 eV/particle 3,675 eV/particle 3,762 eV/particle 3,845 eV/particle 3,926 eV/particle 4,109 eV/particle 4,194 eV/particle 4,286 eV/particle 4,371 eV/particle 4,720 eV/particle 4,800 eV/particle 4,890 eV/particle 4,970 eV/particle 5,580 eV/particle 5,680 eV/particle 5,930 eV/particle 6,030 eV/particle 9,430 eV/particle 9,620 eV/particle 9,810 eV/particle 10,020 eV/particle 10,220 eV/particle 10,410 eV/particle 10,930 eV/particle 11,130 eV/particle 11,360 eV/particle 11,560 eV/particle 12,140 eV/particle 12,310 eV/particle 12,500 eV/particle 12,680 eV/particle 14,560 eV/particle 14,800 eV/particle 15,200 eV/particle 15,400 eV/particle 31,000 eV/particle 31,500 eV/particle 32,000 eV/particle 32,500 eV/particle 39,500 eV/particle 40,100 eV/particle 41,000 eV/particle 41,548 eV/particle 164,764 eV/particle

enthalpy of vaporization
enthalpy of fusion
standard enthalpy of formation
Electron

plisgyn yr electron	2, 8, 18, 32, 31, 8, 2

valence electron	2 ⓘ

trefn yr electronnau	[Rn] 5f¹³ 7s²ⓘ 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 5f¹³ 7s²

Cyflwr ocsidiad	2, 3
Electronegatifedd	0.23542
Electrophilicity Index
cyflwr sylfaenol mater

cyflwr mater	Solid
gaseous state of matter
Boiling Point
Melting Point	1,100.15 K
critical pressure
critical temperature
triple point
appearance
lliw	Colorless #ffffff #b30da6 #b30da6
appearance
Mynegrif plygiant
nodwedd ffisegol gwrthrych
Thermal Conductivity
thermal expansion
molar heat capacity
Specific Heat Capacity
heat capacity ratio
electrical properties
type
dargludedd trydanol
Gwrthedd
superconductivity
magnetism
type
magnetic susceptibility (Mass)
magnetic susceptibility (Molar)
magnetic susceptibility (Volume)
magnetic ordering
Curie temperature
Néel temperature
strwythur
Crystal Structure	()
lattice constant
Lattice Angles
nodwedd mecanyddol deunyddiau
hardness
bulk modulus
shear modulus
Young's modulus
Poisson's ratio
speed of sound
classification
Category	Actinides, Actinides
CAS Group
IUPAC Group
Glawe Number	45
Mendeleev Number	38
Pettifor Number	36
Geochemical Class
Goldschmidt classification	synthetic

other

Gas Basicity
polarizability	109 ± 20 a₀
C6 Dispersion Coefficient
allotrope
Neutron cross section
Neutron Mass Absorption
quantum number	2F7/2
space group	()

Isotopes of Mendelevium

Stable Isotopes	0
Unstable Isotopes	19
Natural Isotopes	0

²⁴⁴Md

Rhif màs	244
neutron number	143
Relative Atomic Mass	244.081157 ± 0.000402 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	0.36 ± 0.14 s
spin	3
nuclear quadrupole moment
dyddiad darganfod	2020
parity	+

decay mode	intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
β⁺ SF (β⁺-delayed fission)	14%

²⁴⁵Md

Rhif màs	245
neutron number	144
Relative Atomic Mass	245.080864 ± 0.000279 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	0.38 ± 0.1 s
spin	7/2
nuclear quadrupole moment
dyddiad darganfod	1996
parity	-

decay mode	intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²⁴⁶Md

Rhif màs	246
neutron number	145
Relative Atomic Mass	246.081713 ± 0.000279 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	0.92 ± 0.18 s
spin	1
nuclear quadrupole moment
dyddiad darganfod	1996
parity	-

decay mode	intensity
α (α emission)	100%

²⁴⁷Md

Rhif màs	247
neutron number	146
Relative Atomic Mass	247.08152 ± 0.000223 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	1.19 ± 0.09 s
spin	7/2
nuclear quadrupole moment
dyddiad darganfod	1981
parity	-

decay mode	intensity
α (α emission)	100%
SF (spontaneous fission)	0.1%

²⁴⁸Md

Rhif màs	248
neutron number	147
Relative Atomic Mass	248.082607 ± 0.000198 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	7 ± 3 s
spin
nuclear quadrupole moment
dyddiad darganfod	1973
parity

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	80%
α (α emission)	20%
β⁺ SF (β⁺-delayed fission)	0.05%

²⁴⁹Md

Rhif màs	249
neutron number	148
Relative Atomic Mass	249.082857155 ± 0.000176516 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	25.6 ± 0.9 s
spin	7/2
nuclear quadrupole moment
dyddiad darganfod	1973
parity	-

decay mode	intensity
α (α emission)	75%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²⁵⁰Md

Rhif màs	250
neutron number	149
Relative Atomic Mass	250.084164934 ± 0.000097606 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	54 ± 4 s
spin	2
nuclear quadrupole moment
dyddiad darganfod	1973
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	93%
α (α emission)	7%
β⁺ SF (β⁺-delayed fission)	0.026%

²⁵¹Md

Rhif màs	251
neutron number	150
Relative Atomic Mass	251.084774287 ± 0.00002031 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	4.21 ± 0.23 m
spin	7/2
nuclear quadrupole moment
dyddiad darganfod	1973
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
α (α emission)	10%

²⁵²Md

Rhif màs	252
neutron number	151
Relative Atomic Mass	252.086385 ± 0.000098 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	2.3 ± 0.8 m
spin	1
nuclear quadrupole moment
dyddiad darganfod	1973
parity	+

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)

²⁵³Md

Rhif màs	253
neutron number	152
Relative Atomic Mass	253.087143 ± 0.000034 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	12 ± 8 m
spin	7/2
nuclear quadrupole moment
dyddiad darganfod	1992
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)	0.7%

²⁵⁴Md

Rhif màs	254
neutron number	153
Relative Atomic Mass	254.08959 ± 0.000107 Da
g-factor	0
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	10 ± 3 m
spin	0
nuclear quadrupole moment	0
dyddiad darganfod	1970
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)

²⁵⁵Md

Rhif màs	255
neutron number	154
Relative Atomic Mass	255.091081702 ± 0.000005976 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	27 ± 2 m
spin	7/2
nuclear quadrupole moment
dyddiad darganfod	1958
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	93%
α (α emission)	7%
SF (spontaneous fission)

²⁵⁶Md

Rhif màs	256
neutron number	155
Relative Atomic Mass	256.093888 ± 0.000133 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	77.7 ± 1.8 m
spin	1
nuclear quadrupole moment
dyddiad darganfod	1955
parity	-

decay mode	intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	90.8%
α (α emission)	9.2%
SF (spontaneous fission)	3%

²⁵⁷Md

Rhif màs	257
neutron number	156
Relative Atomic Mass	257.095537343 ± 0.000001683 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	5.52 ± 0.05 h
spin	7/2
nuclear quadrupole moment
dyddiad darganfod	1965
parity	-

decay mode	intensity
ϵ (electron capture)	85%
α (α emission)	15%
SF (spontaneous fission)

²⁵⁸Md

Rhif màs	258
neutron number	157
Relative Atomic Mass	258.098433634 ± 0.000003729 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	51.59 ± 0.29 d
spin	8
nuclear quadrupole moment
dyddiad darganfod	1970
parity	-

decay mode	intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	0.0015%
β⁻ (β⁻ decay)	0.0015%

²⁵⁹Md

Rhif màs	259
neutron number	158
Relative Atomic Mass	259.100445 ± 0.000108 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	1.6 ± 0.06 h
spin	7/2
nuclear quadrupole moment
dyddiad darganfod	1982
parity	-

decay mode	intensity
SF (spontaneous fission)	100%
α (α emission)

²⁶⁰Md

Rhif màs	260
neutron number	159
Relative Atomic Mass	260.10365 ± 0.000339 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes	27.8 ± 0.8 d
spin
nuclear quadrupole moment
dyddiad darganfod	1989
parity

decay mode	intensity
SF (spontaneous fission)	100%
α (α emission)	5%
ϵ (electron capture)	5%
β⁻ (β⁻ decay)	3.5%

²⁶¹Md

Rhif màs	261
neutron number	160
Relative Atomic Mass	261.105828 ± 0.000546 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes
spin	7/2
nuclear quadrupole moment
dyddiad darganfod
parity	-

decay mode	intensity
α (α emission)

²⁶²Md

Rhif màs	262
neutron number	161
Relative Atomic Mass	262.109144 ± 0.000481 Da
g-factor
natural abundance
Dadfeilio ymbelydrol	☢️ elfen ymbelydrol
Hanner oes
spin
nuclear quadrupole moment
dyddiad darganfod
parity

decay mode	intensity
SF (spontaneous fission)
α (α emission)

hanes

darganfyddwr neu ddyfeisiwr	G.T.Seaborg, S.G.Tompson, A.Ghiorso, K.Street Jr.
man darganfod	United States
dyddiad darganfod	1955
geirdarddiad	Named in honor of the scientist Dmitri Ivanovitch Mendeleyev, who devised the periodic table.
ynganiad	men-deh-LEE-vi-em (Saesneg)

source

Abundance
Abundance in Earth's crust
natural abundance (cefnfor)
natural abundance (corff dynol)	0 %
natural abundance (Awyrfaen)	0 %
natural abundance (Haul)	0 %
Abundance in Universe	0 %

Nuclear Screening Constants

Mendelevi on ChemicalAid

Australian Educational Vocabulary ID	scot/3543
ChEBI ID	33395
ChemSpider ID	22385
DSSTOX compound identifier	DTXCID90147877
DSSTox substance ID	DTXSID90225386
Den Store Danske ID	mendelevium
Elhuyar ZTH ID	028036
Encyclopedia of China (Third Edition) ID	185251
Encyclopedia of China ID (Second Edition)	220827
French Vikidia ID	Mendélévium
GND	4169413-2
Great Russian Encyclopedia Online ID	2204025
InChI	InChI=1S/Md
InChIKey	MQVSLOYRCXQRPM-UHFFFAOYSA-N
OmegaWiki Defined Meaning	335094
PubChem CID	23943
Rhif Cofrestru CAS	7440-11-1
Römpp online ID	RD-13-01207
Store norske leksikon ID	mendelevium
UNII	LW3E571O0Z
USGS Thesaurus ID	1502
dynodwr Encyclopædia Britannica Online	science/mendelevium
dynodwr Encyclopædia Universalis	mendelevium
dynodwr Freebase	/m/025s0rf
dynodwr Gran Enciclopèdia Catalana	0122687
dynodwr ILI	i113965
dynodwr KBpedia	Mendelevium
dynodwr MeSH	D008573
dynodwr Quora	Mendelevium
dynodwr Treccani	mendelevio

Mendelevi (Md)

Nodwedd Ffisegol

Nodwedd Gemegol

other

Isotopes of Mendelevium

244Md

245Md

246Md

247Md

248Md

249Md

250Md

251Md

252Md

253Md

254Md

255Md

256Md

257Md

258Md

259Md

260Md

261Md

262Md

hanes

source

Nuclear Screening Constants

²⁴⁴Md

²⁴⁵Md

²⁴⁶Md

²⁴⁷Md

²⁴⁸Md

²⁴⁹Md

²⁵⁰Md

²⁵¹Md

²⁵²Md

²⁵³Md

²⁵⁴Md

²⁵⁵Md

²⁵⁶Md

²⁵⁷Md

²⁵⁸Md

²⁵⁹Md

²⁶⁰Md

²⁶¹Md

²⁶²Md