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Ra Radium
Element Information, Facts, Properties, Trends, Uses, Comparison with other elements

88
Ra
Radium
Element 88 of Periodic table is Radium with atomic number 88, atomic weight 226. Radium, symbol Ra, has a Body Centered Cubic structure and Silver color. Radium is a Alkaline Earth Metal element. It is part of group 2 (beryllium family). Know everything about Radium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.
88 Ra - Radium | SchoolMyKids

Radium is a chemical element with symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is almost colorless, but it readily combines with nitrogen (rather than oxygen) on exposure to air, forming a black surface layer of radium nitride (Ra3N2).

It belongs to group 2 of the periodic table having trivial name alkaline earth metals*.

Radium Facts

Read key information and facts about element Radium

NameRadium
Atomic Number88
Atomic SymbolRa
Atomic Weight226
PhaseSolid
ColorSilver
Appearancesilvery white metallic
ClassificationAlkaline Earth Metal
Group in Periodic Table2
Group Nameberyllium family
Period in Periodic Tableperiod 7
Block in Periodic Tables -block
Electronic Configuration[Rn] 7s2
Electronic Shell Structure (Electrons per shell)2, 8, 18, 32, 18, 8, 2
Melting Point973 K
Boiling Point2010 K
CAS NumberCAS7440-14-4
Neighborhood Elements
123456789101112131415161718
1
1
H
Hydrogen
1.008

Atomic #

Electronic Shell #

Symbol
Name
Atomic Weight
HGas
HgLiquid
CSolid
Metals
Metalloids
NonMetals
Alkali metals
Alkali earth metals
Lanthanoids
Transition metals
Post-transition metals
Other nonmetals
Halogens
Nobel gas
Actinoids
2
He
Helium
4.003
2
3
Li
Lithium
6.941
4
Be
Beryllium
9.012
5
B
Boron
10.811
6
C
Carbon
12.011
7
N
Nitrogen
14.007
8
O
Oxygen
15.999
9
F
Fluorine
18.998
10
Ne
Neon
20.180
3
11
Na
Sodium
22.990
12
Mg
Magnesium
24.305
13
Al
Aluminium
26.982
14
Si
Silicon
28.085
15
P
Phosphorus
30.974
16
S
Sulfur
32.065
17
Cl
Chlorine
35.453
18
Ar
Argon
39.948
4
19
K
Potassium
39.098
20
Ca
Calcium
40.078
21
Sc
Scandium
44.956
22
Ti
Titanium
47.867
23
V
Vanadium
50.941
24
Cr
Chromium
51.996
25
Mn
Manganese
54.938
26
Fe
Iron
55.845
27
Co
Cobalt
58.933
28
Ni
Nickel
58.693
29
Cu
Copper
63.546
30
Zn
Zinc
65.409
31
Ga
Gallium
69.723
32
Ge
Germanium
72.640
33
As
Arsenic
74.922
34
Se
Selenium
78.960
35
Br
Bromine
79.904
36
Kr
Krypton
83.798
5
37
Rb
Rubidium
85.468
38
Sr
Strontium
87.620
39
Y
Yttrium
88.906
40
Zr
Zirconium
91.224
41
Nb
Niobium
92.906
42
Mo
Molybdenum
95.940
43
Tc
Technetium
98
44
Ru
Ruthenium
101.070
45
Rh
Rhodium
102.906
46
Pd
Palladium
106.420
47
Ag
Silver
107.868
48
Cd
Cadmium
112.411
49
In
Indium
114.818
50
Sn
Tin
118.710
51
Sb
Antimony
121.760
52
Te
Tellurium
127.600
53
I
Iodine
126.904
54
Xe
Xenon
131.293
6
55
Cs
Cesium
132.905
56
Ba
Barium
137.327
57 - 71
La - Lu
Lanthanides
72
Hf
Hafnium
178.490
73
Ta
Tantalum
180.948
74
W
Tungsten
183.840
75
Re
Rhenium
186.207
76
Os
Osmium
190.230
77
Ir
Iridium
192.217
78
Pt
Platinum
195.078
79
Au
Gold
196.967
80
Hg
Mercury
200.590
81
Tl
Thallium
204.383
82
Pb
Lead
207.200
83
Bi
Bismuth
208.980
84
Po
Polonium
209
85
At
Astatine
210
86
Rn
Radon
222
7
87
Fr
Francium
223
88
Ra
Radium
226
89 - 103
Ac - Lr
Actinides
104
Rf
Rutherfordium
261
105
Db
Dubnium
262
106
Sg
Seaborgium
266
107
Bh
Bohrium
264
108
Hs
Hassium
277
109
Mt
Meitnerium
268
110
Ds
Darmstadtium
281
111
Rg
Roentgenium
272
112
Cn
Copernicium
285
113
Nh
Nihonium
284
114
Fl
Flerovium
289
115
Mc
Moscovium
288
116
Lv
Livermorium
292
117
Ts
Tennessine
294
118
Og
Oganesson
294
Lanthanides
57
La
Lanthanum
138.905
58
Ce
Cerium
140.116
59
Pr
Praseodymium
140.908
60
Nd
Neodymium
144.240
61
Pm
Promethium
145
62
Sm
Samarium
150.360
63
Eu
Europium
151.964
64
Gd
Gadolinium
157.250
65
Tb
Terbium
158.925
66
Dy
Dysprosium
162.500
67
Ho
Holmium
164.930
68
Er
Erbium
167.259
69
Tm
Thulium
168.934
70
Yb
Ytterbium
173.040
71
Lu
Lutetium
174.967
Actinides
89
Ac
Actinium
227
90
Th
Thorium
232.038
91
Pa
Protactinium
231.036
92
U
Uranium
238.029
93
Np
Neptunium
237
94
Pu
Plutonium
244
95
Am
Americium
243
96
Cm
Curium
247
97
Bk
Berkelium
247
98
Cf
Californium
251
99
Es
Einsteinium
252
100
Fm
Fermium
257
101
Md
Mendelevium
258
102
No
Nobelium
259
103
Lr
Lawrencium
262

How to Locate Radium on Periodic Table

Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 88 to find Radium on periodic table.

Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Radium on periodic table look for cross section of group 2 and period 7 in the modern periodic table.

Radium History

The element Radium was discovered by P. and M. Curie in year 1898 in France. Radium was first isolated by M. Curie in 1902. Radium derived its name from the Latin radius, 'ray'.

The Curies reported on December 26, 1898, a new element different from polonium, which Marie later isolated fromuraninite.

Radium Presence: Abundance in Nature and Around Us

The table below shows the abundance of Radium in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.

 ppb by weight (1ppb =10^-7 %)ppb by atoms (1ppb =10^-7 %)
Abundance in Universe--
Abundance in Sun--
Abundance in Meteorites--
Abundance in Earth's Crust0.000100.00001
Abundance in Oceans0.000000010.0000000003
Abundance in Humans0.0000010.00000003

Crystal Structure of Radium

The solid state structure of Radium is Body Centered Cubic.

The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure.

Unit Cell Parameters

The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c)

abc
514.8 pm514.8 pm514.8 pm

and the angles between them Lattice Angles (alpha, beta and gamma).

alphabetagamma
π/2 π/2 π/2

The positions of the atoms inside the unit cell are described by the set of atomic positions ( xi, yi, zi) measured from a reference lattice point.

The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.

Space Group NameIm_ 3m 88 Ra Radium - Crystal Structure | SchoolMyKids
Oxidation StatesSpace Group Number229
Crystal StructureBody Centered Cubic

Radium Atomic and Orbital Properties

Radium atoms have 88 electrons and the electronic shell structure is [2, 8, 18, 32, 18, 8, 2] with Atomic Term Symbol (Quantum Numbers) 1S0.

Atomic Number88
Number of Electrons (with no charge)88
Number of Protons88
Mass Number226
Number of Neutrons138
Shell structure (Electrons per energy level)2, 8, 18, 32, 18, 8, 2
Electron Configuration[Rn] 7s2
Valence Electrons7s2
Valence (Valency)2
Main Oxidation States2
Oxidation States2
Atomic Term Symbol (Quantum Numbers)1S0

Bohr Atomic Model of Radium - Electrons per energy level

88 Ra Radium - Electron Shell Structure | SchoolMyKids
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Ground State Electronic Configuration of Radium - neutral Radium atom

Abbreviated electronic configuration of Radium

The ground state abbreviated electronic configuration of Neutral Radium atom is [Rn] 7s2. The portion of Radium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Rn]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used. This is important as it is the Valence electrons 7s2, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Radium

Complete ground state electronic configuration for the Radium atom, Unabbreviated electronic configuration

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 7s2

Electrons are filled in atomic orbitals as per the order determined by the Aufbau principle, Pauli Exclusion Principle and Hund’s Rule.

  • As per the Aufbau principle the electrons will occupy the orbitals having lower energies before occupying higher energy orbitals. According to this principle, electrons are filled in the following order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p…
  • The Pauli exclusion principle states that a maximum of two electrons, each having opposite spins, can fit in an orbital.
  • Hund's rule states that every orbital in a given subshell is singly occupied by electrons before a second electron is filled in an orbital.
  • Electron configuration of Radium
    Atomic Structure of Radium

    Radium atomic radius is - , while it's covalent radius is - .

    Atomic Radius Calculated

    - (0 Å)

    Atomic Radius Empirical

    215 pm (2.15 Å)

    Atomic Volume41.09 cm3/mol
    Covalent Radius-
    Van der Waals Radius283 pm
    Neutron Cross Section20
    Neutron Mass Absorption -

    Atomic Spectrum of Radium

    Atomic Spectrum of Radium | SchoolMyKids

    Radium Chemical Properties: Radium Ionization Energies and electron affinity

    The electron affinity of Radium is - .

    Valence2
    Electronegativity0.9
    ElectronAffinity-

    Ionization Energy of Radium

    Refer to table below for Ionization energies of Radium

    Ionization energy numberEnthalpy - kJ/mol
    1st509.3
    2nd979

    Radium Physical Properties

    Refer to below table for Radium Physical Properties

    Density5 g/cm3
    Molar Volume41.09 cm3/mol

    Elastic Properties

    Young Modulus-
    Shear Modulus-
    Bulk Modulus -
    Poisson Ratio-

    Hardness of Radium - Tests to Measure of Hardness of Element

    Mohs Hardness-
    Vickers Hardness-
    Brinell Hardness-

    Radium Electrical Properties

    Radium is Conductor of electricity. Refer to table below for the Electrical properties ofRadium

    Electrical Conductivity1000000 S/m
    Resistivity0.000001 m Ω
    Superconducting Point-

    Radium Heat and Conduction Properties

    Thermal Conductivity19 W/(m K)
    Thermal Expansion-

    Radium Magnetic Properties

    Magnetic Type-
    Curie Point-
    Mass Magnetic Susceptibility-
    Molar Magnetic Susceptibility-
    Volume Magnetic Susceptibility-

    Optical Properties of Radium

    Refractive Index-

    Acoustic Properties of Radium

    Speed of Sound-

    Radium Thermal Properties - Enthalpies and thermodynamics

    Refer to table below for Thermal properties of Radium

    Melting Point973 K (699.85°C, 1291.73 °F)
    Boiling Point2010 K (1736.85°C, 3158.33 °F)
    Critical Temperature-
    Superconducting Point-

    Enthalpies of Radium

    Heat of Fusion8 kJ/mol
    Heat of Vaporization125 kJ/mol
    Heat of Combustion-

    Radium Isotopes - Nuclear Properties of Radium

    Radium has 33 isotopes, with between 202 and 234 nucleons. Radium has 0 stable naturally occuring isotopes.

    Isotopes of Radium - Naturally occurring stable Isotopes: -.

    IsotopeZNIsotope Mass% AbundanceT halfDecay Mode
    202Ra88114202Synthetic
    203Ra88115203Synthetic
    204Ra88116204Synthetic
    205Ra88117205Synthetic
    206Ra88118206Synthetic
    207Ra88119207Synthetic
    208Ra88120208Synthetic
    209Ra88121209Synthetic
    210Ra88122210Synthetic
    211Ra88123211Synthetic
    212Ra88124212Synthetic
    213Ra88125213Synthetic
    214Ra88126214Synthetic
    215Ra88127215Synthetic
    216Ra88128216Synthetic
    217Ra88129217Synthetic
    218Ra88130218Synthetic
    219Ra88131219Synthetic
    220Ra88132220Synthetic
    221Ra88133221Synthetic
    222Ra88134222Synthetic
    223Ra88135223Synthetic
    224Ra88136224Synthetic
    225Ra88137225Synthetic
    226Ra88138226Synthetic1.59×10^3 yearsAlphaEmission
    227Ra88139227Synthetic
    228Ra88140228Synthetic
    229Ra88141229Synthetic
    230Ra88142230Synthetic
    231Ra88143231Synthetic
    232Ra88144232Synthetic
    233Ra88145233Synthetic
    234Ra88146234Synthetic

    Regulatory and Health - Health and Safety Parameters and Guidelines

    Database Search

    List of unique identifiers to search the element in various chemical registry databases

    DatabaseIdentifier number
    CAS Number - Chemical Abstracts Service (CAS)CAS7440-14-4
    RTECS Number-
    CID Number CID6328144
    Gmelin NumberGmelin40437
    NSC Number-