Mendeleev's Periodic Table > Ba - Barium

Ba - Barium

An alkaline earth element, barium is also a toxic heavy metal. Minerals containing barium were identified by Karl Scheele in 1774 from which the pure metal was electrolysed by Humphrey Davy in 1808.

Atomic number - 56 Density g/mL 3 .5
Atomic weight u 137 .33 Melting point K 1002
Bonding radius A 1 .98 Boiling point K 2171
Atomic radius A 2 .78 Heat of vaporization kJ/mol 142
Ionization Potential V 5 .212 Heat of fusion kJ/mol 7 .75
Electronegativity - 0 .89 Specific heat J/gK 0 .204
The oxide is a strong base. Crystal are body centered cubic.
Electron config. : [Xe] 6s2

Isotopes of Ba (Barium):

MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 114
0.43 sec
a/EC,8.900
Xe-110/Cs-114
113.95093 		115
0.4 sec
EC,5.800 MeV
Cs-115
114.94771 		116
1.35 sec
EC,6.700 MeV
Cs-116
115.94170 		117
1.75 sec
EC/ECa/ECp,9.500
Cs-117/I-113/Xe-116
116.93880
MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 118
5.2 sec
EC,11.080 MeV
Cs-118
117.93344 		119
5.4 sec
EC/ECp,8.100
Cs-119/Xe-118
118.93107 		120
32 sec
EC,5.000 MeV
Cs-120
119.92603 		121
29.5 sec
EC/ECp,6.800
Cs-121/Xe-120
120.92452
MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 122
1.95 min
EC,3.800 MeV
Cs-122
121.92023 		123
2.7 min
EC,5.500 MeV
Cs-123
122.91884 		124
11.9 min
EC,2.646 MeV
Cs-124
123.91508 		125
3.5 min
EC,4.600 MeV
Cs-125
124.91465
MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 126
100 min
EC,1.673 MeV
Cs-126
125.91124 		127
12.7 min
EC,3.450 MeV
Cs-127
126.91112 		128
2.43 da
EC,3.930 MeV
Cs-128
127.90830 		129
2.23 hr
EC,2.432 MeV
Cs-129
128.90867
MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 130 0.106%

Stable

129.90631 		131
11.50 da
EC,1.370 MeV
Cs-131
130.90693 		132 0.101%

Stable

131.90505 		133
10.51 yr
EC,5.500 MeV
Cs-133
132.90600
MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 133a
38.9 hr
EC,5.500 MeV
Cs-133
132.90631 		134 2.417%

Stable

133.90450 		135 6.592%

Stable

134.90568 		136 7.854%

Stable

135.90457
MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 137 11.23%

Stable

136.90582 		138 71.70%

Stable

137.90524 		139
83.06 min
B-,2.317 MeV
La-139
138.90883 		140
12.752 da
B-,1.047 MeV
La-140
139.91059
MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 141
18.27 min
B-,3.216 MeV
La-141
140.91441 		142
10.6 min
B-,2.212 MeV
La-142
141.91645 		143
14.33 sec
B-,4.243 MeV
La-143
142.92061 		144
11.5 sec
B-/B-n,3.120
La-144/La-143
143.92294
MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 145
4.31 sec
B-,4.930 MeV
La-145
144.92694 		146
2.22 sec
B-,4.120 MeV
La-146
145.93017 		147
0.893 sec
B-/B-n,5.750
La-147/La-146
146.93398 		148
0.607 sec
B-/B-n,5.120
La-148/La-147
147.93768
MASS abundancy
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass		 149
0.344 sec
B-/B-n,7.300
La-149/La-148
148.94202 		150
0.3 sec
B-,6.600 MeV
La-150
149.94557