niobium vs tantalum

niobium (chemical element) | tantalum (chemical element)

Periodic table location

Images

| niobium | tantalum atomic symbol | Nb | Ta atomic number | 41 | 73 short electronic configuration | [Kr]5s^14d^4 | [Xe]6s^24f^145d^3 Aufbau diagram | 4d 5s | 5d 4f 6s block | d | d group | 5 | 5 period | 5 | 6 atomic mass | 92.90637 u | 180.94788 u half-life | (stable) | (stable)

| niobium | tantalum phase at STP | solid | solid melting point | 2477 °C | 3017 °C boiling point | 4744 °C | 5458 °C molar heat of fusion | 26.8 kJ/mol | 36 kJ/mol molar heat of vaporization | 690 kJ/mol | 735 kJ/mol specific heat at STP | 265 J/(kg K) | 140 J/(kg K) (properties at standard conditions)

| niobium | tantalum density | 8.57 g/cm^3 | 16.65 g/cm^3 liquid density | | 15 g/cm^3 molar volume | 10.84 cm^3/mol | 10.868 cm^3/mol Mohs hardness | 6 (≈ microcline) | 6.5 (between microcline and quartz) Vickers hardness | 1320 MPa | 873 MPa Brinell hardness | 736 MPa | 800 MPa bulk modulus | 170 GPa | 200 GPa shear modulus | 38 GPa | 69 GPa Young's modulus | 105 GPa | 186 GPa Poisson ratio | 0.4 | 0.34 sound speed | 3480 m/s | 3400 m/s thermal expansion | 7.3×10^-6 K^(-1) | 6.3×10^-6 K^(-1) thermal conductivity | 54 W/(m K) | 57 W/(m K) (properties at standard conditions)

| niobium | tantalum electrical type | conductor | conductor resistivity | 1.5×10^-7 Ω m (ohm meters) | 1.3×10^-7 Ω m (ohm meters) electrical conductivity | 6.7×10^6 S/m (siemens per meter) | 7.7×10^6 S/m (siemens per meter) magnetic type | paramagnetic | paramagnetic volume magnetic susceptibility | 2.37×10^-4 | 1.782×10^-4 mass magnetic susceptibility | 2.76×10^-8 m^3/kg (cubic meters per kilogram) | 1.07×10^-8 m^3/kg (cubic meters per kilogram) molar magnetic susceptibility | 2.56×10^-9 m^3/mol (cubic meters per mole) | 1.936×10^-9 m^3/mol (cubic meters per mole) work function | (3.95 to 4.87) eV | (4 to 4.8) eV threshold frequency | (9.551×10^14 to 1.178×10^15) Hz (hertz) | (9.672×10^14 to 1.161×10^15) Hz (hertz) superconducting point | 9.25 K (kelvins) | 4.47 K (kelvins) color | (gray) | (gray)

| niobium | tantalum valence | 5 | 5 electronegativity | 1.6 | 1.5 electron affinity | 86.1 kJ/mol (kilojoules per mole) | 31 kJ/mol (kilojoules per mole) first ionization energy | 652.1 kJ/mol (kilojoules per mole) | 761 kJ/mol (kilojoules per mole) ionization energies | 652.1 kJ/mol | 1380 kJ/mol | 2416 kJ/mol | 3700 kJ/mol | 4877 kJ/mol | 9847 kJ/mol | 12100 kJ/mol | 761 kJ/mol | 1500 kJ/mol

Reactivity

| niobium | tantalum term symbol | ^6D_(1/2) | ^4F_(3/2) atomic radius | 145 pm | 145 pm covalent radius | 164 pm | 170 pm (electronic ground state properties)

| niobium | tantalum universe abundance | 2×10^-7 mass% | 8×10^-9 mass% solar abundance | 4×10^-7 mass% | meteorite abundance | 1.9×10^-5 mass% | 2×10^-6 mass% crust abundance | 0.0017 mass% | 1.7×10^-4 mass% ocean abundance | 1×10^-10 mass% | 2×10^-10 mass% universe molar abundance | 0 mol% | 6×10^-11 mol% solar molar abundance | 5×10^-9 mol% | meteorite molar abundance | 3×10^-6 mol% | 2×10^-7 mol% ocean molar abundance | 6.7×10^-12 mol% | 6.8×10^-12 mol% crust molar abundance | 3.7×10^-4 mol% | 1.9×10^-5 mol%

| niobium | tantalum half-life | (stable) | (stable) stable isotopes | Nb-93 (100%) | Ta-181 (99.988%) nuclear spin | Nb-81: 3/2^- | Nb-82: 0^+ | Nb-83: 5/2^+ | Nb-84: 3^+ | Nb-85: 9/2^+ | Nb-86: 6^+ | Nb-87: 1/2^- | Nb-88: 8^+ | Nb-89: 9/2^+ | Nb-90: 8^+ | Nb-91: 9/2^+ | Nb-92: 7^+ | Nb-93: 9/2^+ | Nb-94: 6^+ | Nb-95: 9/2^+ | Nb-96: 6^+ | Nb-97: 9/2^+ | Nb-98: 1^+ | Nb-99: 9/2^+ | Nb-100: 1^+ | Nb-101: 5/2^+ | Nb-102: 1^+ | Nb-103: 5/2^+ | Nb-104: 1^+ | Nb-105: 5/2^+ | Nb-106: 2^+ | Nb-107: 5/2^+ | Nb-108: 2^+ | Nb-109: 5/2^+ | Nb-110: 2^+ | Nb-111: 5/2^+ | Nb-112: 2^+ | Nb-113: 5/2^+ | Ta-155: 11/2^- | Ta-156: 2^- | Ta-157: 1/2^+ | Ta-158: 2^- | Ta-159: 1/2^- | Ta-160: 2^- | Ta-161: 1/2^+ | Ta-162: 3^+ | Ta-163: 1/2^+ | Ta-164: 3^+ | Ta-165: 5/2^- | Ta-166: 2^+ | Ta-167: 3/2^+ | Ta-169: 5/2^+ | Ta-170: 3^+ | Ta-171: 5/2^- | Ta-172: 3^+ | Ta-173: 5/2^- | Ta-174: 3^+ | Ta-175: 7/2^+ | Ta-176: 1^- | Ta-177: 7/2^+ | Ta-178: 7^- | Ta-179: 7/2^+ | Ta-180: 1^+ | Ta-181: 7/2^+ | Ta-182: 3^- | Ta-183: 7/2^+ | Ta-184: 5^- | Ta-185: 7/2^+ | Ta-187: 7/2^+ | Ta-189: 7/2^+ unstable isotopes | Nb-92 (35 Myr) | Nb-94 (20300 yr) | Nb-91 (682 yr) | Nb-95 (34.991 days) | Nb-96 (23.35 h) | Nb-90 (14.6 h) | Nb-89 (121.8 min) | Nb-97 (72.17 min) | Nb-88 (14.55 min) | Nb-87 (225 s) | Nb-86 (88 s) | Nb-85 (20.9 s) | Nb-99 (15 s) | Nb-84 (9.5 s) | Nb-101 (7.1 s) | Nb-104 (4.9 s) | Nb-83 (4.1 s) | Nb-105 (2.95 s) | Nb-98 (2.86 s) | Nb-103 (1.5 s) | Nb-100 (1.5 s) | Nb-102 (1.3 s) | Nb-106 (930 ms) | Nb-81 (800 ms) | Nb-107 (330 ms) | Nb-108 (193 ms) | Nb-109 (190 ms) | Nb-110 (170 ms) | Nb-111 (80 ms) | Nb-82 (50 ms) | Nb-113 (30 ms) | Nb-112 (150 ns) | Ta-179 (1.82 yr) | Ta-182 (114.43 days) | Ta-183 (120 h) | Ta-177 (56.56 h) | Ta-175 (10.5 h) | Ta-184 (8.6 h) | Ta-180 (8.1528 h) | Ta-176 (8.08 h) | Ta-173 (188 min) | Ta-178 (142 min) | Ta-174 (68 min) | Ta-185 (49.33 min) | Ta-172 (36.83 min) | Ta-171 (23 min) | Ta-186 (10.5 min) | Ta-170 (6.77 min) | Ta-169 (4.83 min) | Ta-187 (120 s) | Ta-168 (120 s) | Ta-167 (79.8 s) | Ta-166 (34.4 s) | Ta-165 (31 s) | Ta-188 (20 s) | Ta-164 (14.2 s) | Ta-163 (10.6 s) | Ta-162 (3.57 s) | Ta-189 (3 s) | Ta-161 (3 s) | Ta-160 (1.55 s) | Ta-159 (830 ms) | Ta-190 (300 ms) | Ta-156 (144 ms) | Ta-158 (55 ms) | Ta-157 (10.1 ms) | Ta-155 (13 µs) neutron cross-section | 1.15 b | 20.5 b neutron mass absorption | 4×10^-4 m^2/kg | 0.0041 m^2/kg

| niobium | tantalum CAS number | 7440-03-1 | 7440-25-7 PubChem CID number | 23936 | 23956