Main page (Russian)
Search in database (English)
Properties of substance:
niobium
Group of substances:
inorganic
Physical appearance:
cubic metal
Empirical formula (Hill's system for organic substances):
Nb
Structural formula as text:
Nb
Molar/atomic mass: 92.91
Melting point (°C):
2470
Boiling point (°C):
4760
Solubility (g/100 g of solvent):
lithium molten
: 0.0008 (700°C) [
Ref.
]
mercury
: insoluble [
Ref.
]
potassium fused
: 0.0001 (700°C) [
Ref.
]
sodium fused
: 0.0035 (700°C) [
Ref.
]
water
: insoluble [
Ref.
]
Numerical data:
Year of discovery: 1801
Superconducting temperature (K): 9.3
Density:
8.57 (20°C, g/cm
3
)
Reactions:
[
Ref.1
]
4Nb + 5O
2
→ 2Nb
2
O
5
Half-life:
100
41
Nb = 1.5 s (β
-
(100%))
100m
41
Nb = 2.99 s (β
-
(100%))
100n
41
Nb = 460 ns (internal transition (100%))
100p
41
Nb = 12.43 μs (internal transition (100%))
101
41
Nb = 7.1 s (β
-
(100%))
102
41
Nb = 4.3 s (β
-
(100%))
102m
41
Nb = 1.3 s (β
-
(100%))
103
41
Nb = 1.5 s (β
-
(100%))
104
41
Nb = 4.9 s (β
-
(100%), β
-
n (0.06%))
104m
41
Nb = 940 ms (β
-
(100%), β
-
n (0.05%))
105
41
Nb = 2.95 s (β
-
(100%), β
-
n (1.7%))
106
41
Nb = 1050 ms (β
-
(100%), β
-
n (4.5%))
106m
41
Nb = 800 ns (internal transition (100%))
106n
41
Nb = 849 ns (internal transition (100%))
107
41
Nb = 289 ms (β
-
(100%), β
-
n (7.4%))
108
41
Nb = 198 ms (β
-
(100%), β
-
n (6.3%))
108m
41
Nb = 109 ns (internal transition (100%))
109
41
Nb = 106.9 ms (β
-
(100%), β
-
n (31%))
109m
41
Nb = 115 ns (internal transition (100%))
110
41
Nb = 82 ms (β
-
(100%), β
-
n (40%), β
-
2n)
111
41
Nb = 54 ms (β
-
(100%), β
-
n. β
-
2n)
112
41
Nb = 38 ms (β
-
(100%), β
-
n. β
-
2n)
113
41
Nb = 32 ms (β
-
(100%), β
-
n. β
-
2n)
114
41
Nb = 17 ms (β
-
(100%), β
-
n. β
-
2n)
115
41
Nb = 23 ms (β
-
(100%), β
-
n. β
-
2n)
82
41
Nb = 50 ms (β
+
(100%))
82m
41
Nb = 92 ns (internal transition (100%))
83
41
Nb = 3.9 s (β
+
(100%))
84
41
Nb = 9.8 s (β
+
(100%))
84m
41
Nb = 176 ns (internal transition (100%))
84n
41
Nb = 92 ns (internal transition (100%))
85
41
Nb = 20.5 s (β
+
(100%))
85m
41
Nb = 3.3 s ()
86
41
Nb = 88 s (β
+
(100%))
86m
41
Nb = 56.3 s (β
+
(100%))
87
41
Nb = 3.7 min (β
+
(100%))
87m
41
Nb = 2.6 min (β
+
(100%))
88
41
Nb = 14.50 min (β
+
(100%))
88m
41
Nb = 7.7 min (β
+
(100%))
89
41
Nb = 2.03 hasа (β
+
(100%))
89m
41
Nb = 1.10 hasа (β
+
(100%))
90
41
Nb = 14.60 hasа (β
+
(100%))
90m
41
Nb = 63 μs (internal transition (100%))
90n
41
Nb = 18.81 s (internal transition (100%))
90p
41
Nb = < 1 μs (internal transition (100%))
90q
41
Nb = 6.19 ms (internal transition (100%))
90r
41
Nb = 472 ns (internal transition (100%))
91
41
Nb = 680 y (electron capture (about 100%), позитронный распад (0.0138%))
91m
41
Nb = 60.86 d (internal transition (96.6%), electron capture (3.4%), позитронный распад (0.0028%))
91n
41
Nb = 3.76 μs (internal transition (100%))
92
41
Nb = 34 700 000 y (β
+
(100%))
92m
41
Nb = 10.15 d (β
+
(100%))
92n
41
Nb = 5.9 μs (internal transition (100%))
92p
41
Nb = 167 ns (internal transition (100%))
93
41
Nb = stable ( (isotopic abundance 100%))
93m
41
Nb = 16.12 y (internal transition (100%))
93n
41
Nb = 1.5 μs ()
94
41
Nb = 20 400 y (β
-
(100%))
94m
41
Nb = 6.263 min (internal transition (99.50%), β
-
(0.50%))
95
41
Nb = 34.991 d (β
-
(100%))
95m
41
Nb = 3.61 d (internal transition (94.4%), β
-
(5.6%))
96
41
Nb = 23.35 h (β
-
(100%))
97
41
Nb = 72.1 min (β
-
(100%))
97m
41
Nb = 58.7 s (internal transition (100%))
98
41
Nb = 2.86 s (β
-
(100%))
98m
41
Nb = 51.3 min (β
-
(about 100%))
99
41
Nb = 15.0 s (β
-
(100%))
99m
41
Nb = 2.5 min ()
Vapour pressure (Torr):
0.1 (2980°C)
1 (3300°C)
10 (3780°C)
100 (4240°C)
Electrode potential:
Nb
3+
+ 3e
-
→ Nb, E = -1.1 V (water, 25°C)
Standard molar enthalpy (heat) of formation Δ
f
H
0
(298.15 K, kJ/mol):
0 (s)
Standard molar Gibbs energy of formation Δ
f
G
0
(298.15 K, kJ/mol):
0 (s)
Standard molar entropy S
0
(298.15 K, J/(mol·K)):
36.6 (s)
Molar heat capacity at constant pressure C
p
(298.15 K, J/(mol·K)):
24.6 (s)
Molar enthalpy (heat) of fusion Δ
fus
H (kJ/mol):
28
Enthalpy (heat) of vaporization Δ
vap
H (kJ/mol):
662
Standard molar enthalpy (heat) of formation Δ
f
H
0
(298.15 K, kJ/mol):
723 (g)
Standard molar entropy S
0
(298.15 K, J/(mol·K)):
186.2 (g)
Molar heat capacity at constant pressure C
p
(298.15 K, J/(mol·K)):
30.2 (g)
References:
Гибало И.М. Аналитическая химия ниобия и тантала. - М.: Наука, 1967. - pp. 14-15 [Russian]
Гурвич Я.А. Справочник молодого аппаратчика-химика. - М.: Химия, 1991. - pp. 51 [Russian]
Ниобий и тантал. - М.: Металлургия, 1990 [Russian]
Рабинович В.А., Хавин З.Я. Краткий химический справочник. - Л.: Химия, 1977. - pp. 88 [Russian]
Редкие и рассеянные элементы. Химия и технология. - Кн. 2. - М.: Мисис, 1998. - pp. 258-262 [Russian]
Химическая энциклопедия. - Т. 3. - М.: Советская энциклопедия, 1992. - pp. 249-251 [Russian]
What information do you need?
© Collected Ruslan Anatolievich Kiper, burewestnik@mail.ru
Search in database (English)