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Radium
Radium
Identification
Symbol
Ra
Block
Group
Group 2a
Period
7
Atomic Information
Atomic Number
88
Atomic Radius
283 pm
Mass
226 Ar
Category
Metal
Standard state(298 K)
Solid (20oC)
Electronic Configuration
[Rn] 7s2
Electronegativity (Pauling)
0.9
9.65 kJ mol−1
First ionisation energy
509.29 kJ mol−1
Physical Properties
Color
Silver white
Melting Point
973 K
Boiling Point
1413 K
Density of solid
5 g/cm3
Unknown
Heat Properties
Enthalpy of fusion
Unknown
Enthalpy of atomisation
Unknown
Enthalpy of vaporisation
Unknown


Radium() is a radiactive chemical element, and the heaviest of the Alkaline-earth metals of the periodic table. It is a silvery white metal and does not occur freely in nature.

Discovery[]

Radium was discovered by Marie Curie, a Polish chemist, and Pierre Curie, a French chemist, in 1898. They obtained raidum from pitchblende, a material that contains uranium, after noticing that unrefined pitchblende was more radioactive than the uranium that was separated from it. They speculated that pitchblende must contain another radioactive element. They refined severals tons of pitchblende in order to obtain tiny amounts of radium and polonium, another radioactive element discovered by Madam Curie.

Curie[]

Curie is a unit used to desribe the activity of a radioactive substance based on radium-226 isotope. It is equal to the number of atoms in one gram sample of radium-226 that will decay in one second, or .

Uses[]

Radium was used to make self-luminous paints for watches, aircraft instrument dials and other instrumentation, but has now been replaced by cobalt-60, which is a less dangerous radioactive material.

A mixture of radium and beryllium will emit neutrons and is used as a neutron source.

Radium is used to produce radon, a radioactive gas used to treat some types of cancer. A single gram of radium-226 will produce ml of radon a day.

Periodic Table

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
* 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
** 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
119
Uue
120
Ubn
*** 158
Ups
159
Upo
160
Upe
161
Uhn


* 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
** 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
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