ANTIMONY
NITROGEN GROUP
| Atomic number: | 51 |
| Group numbers: | 15 |
| Period: | 5 |
| Electronic configuration: | [Kr] 4d10 5s2 5p3 |
| Formal oxidation number: | -3 +3 +5 |
| Electronegativities: | 2.05 |
| Atomic radius / pm: | 145 |
| Relative atomic mass: | 121.760(1) |
Antimony has been known since ancient times. The origin of the name comes from the Latin word stibium meaning mineral stibnite. It is a hard, brittle, silvery-white semimetal that is stable in dry air. It is toxic by ingestion or inhalation. Antimony is found in stibnite (Sb2S3) and in valentinite (Sb2O3). It is alloyed with other metals to increase their hardness. It is used in the manufacture of a few special types of semiconductor devices, also in plastics and chemicals. A few kinds of over-the-counter cold and flu remedies use antimony compounds. The price of 99.9 % pure antimony ingot is 153.50 € for 450 g.
| Density / g dm-3: | 6691 | (293 K) |
| 6483 | (m.p.) | |
| Molar volume / cm3mol-1: | 18.20 | (293 K) |
| 18.78 | (m.p.) | |
| Electrical resistivity / µΩcm: | 39 | (20 °C) |
| Thermal conductivity / W m-1K-1: | 24.3 |
| Melting point / °C: | 630.63 |
| Boiling point / °C: | 1587 |
| Heat of fusion / kJ mol-1: | 20.9 |
| Heat of vaporization / kJ mol-1: | 165.8 |
| Heat of atomization / kJ mol-1: | 262.04 |
| First ionization energy / kJ mol-1: | 830.59 |
| Second ionization energy / kJ mol-1: | 1594.96 |
| Third ionization energy / kJ mol-1: | 2441.10 |
| in the atmosphere / ppm: | - |
| in the Earth's crust / ppm: | 0.2 |
| in the oceans / ppm: | 0.0005 |
| Crystal structure: | rhombohedral |
| Unit-cell dimensions / pm: | a=430.84, c=1124.7 |
| Space group: | R3m |
| Isotope | Relative atomic mass | Mass percent (%) |
|---|---|---|
| 121Sb | 120.903818(2) | 57.36(8) |
| 123Sb | 122.904216(2) | 42.64(8) |
| Balanced half-reaction | Eo / V | |
|---|---|---|
| SbV + 2e- → SbIII | +0.818 | (6 mol dm-3 HCl) |
| SbV + 2e- → SbIII | +0.746 | (3.5 mol dm-3 HCl) |
| SbO+ + 2H+ + 3e- → Sb(s) + H2O | +0.212 | |
| SbO3- + 2H+ + 2e- → SbO2- + H2O | +0.353 | |
| SbO3- + 3H+ + 2e- → HSbO2 + H2O | +0.678 | |
| SbO3- + 4H+ + 2e- → SbO+ + 2H2O | +0.704 | |
| SbO2- + 2H+ + 2e- → SbO- + H2O | +0.720 | |
| 2SbO3- + 6H+ + 4e- → Sb2O3(s) + 3H2O | +0.772 | |
| SbO2- + 4H+ + 3e- → Sb(s) + 2H2O | +0.446 | |
| HSbO2 + 3H+ + 3e- → Sb(s) + 2H2O | +0.230 | |
| Sb2O3(s) + 6H+ + 6e- → 2Sb(s) + 3H2O | +0.152 | |
| Sb2O5(s) + 6H+ + 4e- → 2SbO+ + 3 H2O | +0.581 | |
| Sb2O5(s) + 4H+ + 4e- → Sb2O3(s) + 2H2O | +0.692 | |
| Sb(s) + 3H+ + 3e- → SbH3(g) | - 0.510 |
| 50 Tin | ← | 51 Antimony | → | 52 Tellurium |
Citing this page:
Generalic, Eni. "Antimony." EniG. Periodic Table of the Elements. KTF-Split, 18 Jan. 2024. Web. {Date of access}. <https://www.periodni.com/sb.html>.
