Bismuth

Bi. Atomic number 83. Nonmetallic element in group 15 of the periodic table with the electron configuration [Xe]4f ¹⁴ 5d ¹⁰ 6s ² 6p ^3. Atomic weight 208.98040(1). Non-radioactive element with the highest atomic number. Mononuclear element with only one stable nuclide, the isotope with mass number 209. Radioactive isotopes with mass numbers from 184 to 218. It was considered to be a mixture of lead and tin for over a thousand years, but it was discovered to be a pure metal in the 16th century. It is called Paracelsus Wismuth, but the origin of the name is said to be from the German "weiße Masse" (white mass) because the oxide is white. The German name of the element is Bismut, and the English and French names are bismuth. There are various theories about the origin of the name, including one that it comes from the Arabic word "meltable". In 1773, it was discovered to be a new element by C. Geoffroy of France. In his book "Semitsu Kaisyo" published in 1837, Udagawa Yoan states that it is bismuth bismuth.
Its main ores are bismuthinite (Bi ₂ S _{3 )} , bismuth oxide (Bi ₂ O _{3 )} , and bismatite (BiO) ₂ CO _3. Its abundance in the earth's crust is 0.06 ppm. China accounts for 75% of the 320 million tons of recoverable reserves, followed by Peru, Bolivia, and Mexico, each with about 3%. It is one of the chalcophile elements. It is mainly obtained as a by-product from the electrolytic slime of lead smelting. The elemental form is silvery white with a reddish tinge. It has a trigonal crystal system. The metal is brittle. Its density is 9.747 g cm ^-3 (20 °C), and its liquid form is 10.05 g cm ^-3 (melting point). Its melting point is 271.3 °C, and its boiling point is 1610 °C. In the gas phase, it forms ₂ Bi molecules. First ionization energy is 7.289 eV. The ionic radius is 0.117 nm for Bi ³⁺ (hexacoordinated) and 0.090 nm for Bi ⁵⁺ (hexacoordinated). The standard electrode potential of ^{Bi 3+} /Bi is +0.32 V, and the ionization tendency is small. It has the strongest diamagnetic property of all elements and the lowest thermal conductivity of all metals after mercury. Bismuth, like gallium, is one of the few metals whose volume increases (3.5%) when solidified from a liquid. It does not dissolve in non-oxidizing acids, but dissolves in nitric acid and aqua regia to produce bismuth(III) salts. In air, it burns at high temperatures to produce Bi ₂ O _3. It reacts with halogens to produce BiCl ₃ (white), BiBr ₃ (golden yellow), BiI ₃ (green-black), and BiF _5. Compounds with BiCl 3 usually have an oxidation number of 3, but compounds with an oxidation number of 5 are strong oxidizers (e.g., M ^Ⅰ BiO ₃ ).
A melting metal used in lead-free solder, thermal fuses for sprinklers, etc. Its main uses include as a metallurgical additive, additive to improve the machinability of steel, ferrite for magnets and memory, and for low melting point alloys. It is also used as an antibacterial agent, medicine (antacids, etc.), and petrochemical catalyst. Newer uses include optical recording media (CD-R, CD-RW) and protective film material for magneto-optical recording (MD, MO). It is also known as a component of high temperature superconductors (bismuth-based). [CAS 7440-69-9][See alternative terms] Bismuth compounds

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

Bi．原子番号83の元素．電子配置[Xe]4f ¹⁴5d¹⁰6s²6p³の周期表15族非金属元素．原子量208.98040(1)．もっとも高い原子番号の非放射性元素．安定核種が質量数209の同位体のみの単核種元素．質量数184～218の放射性同位体がある．千年以上前から鉛，スズの混合物の一つとみなされて使われていたが，16世紀には純金属であることがわかっていた．Paracelsus Wismuthとよんでいるが，語源は酸化物が白いところから，ドイツ語の“白い塊”，weiße Masseにちなむとされる．ドイツ語の元素名はBismut，英語・フランス語名はbismuthである．アラビア語の“融けやすい”が語源という説のほか，諸説がある．1773年，フランスのC. Geoffroyにより新元素であることが示された．宇田川榕菴は天保8年(1837年)に出版した「舎密開宗」で，亜比斯繆母(ピスシュテュム)蒼鉛としている．
輝蒼鉛鉱Bi₂S₃，蒼鉛華Bi₂O₃，ビスマタイト(BiO)₂CO₃などが主要鉱石である．地殻中の存在度0.06 ppm．可採埋蔵量320百万t の75％ が中国，以下ペルー，ボリビア，メキシコが各約3％．親銅元素の一つ．おもに鉛精錬の電解スライムから副産物として得られる．単体は赤味を帯びた銀白色．三方晶系．金属はもろい．密度9.747 g cm^－3(20 ℃)，液体10.05 g cm^－3(融点)．融点271.3 ℃，沸点1610 ℃．気相では Bi₂ 分子となる．第一イオン化エネルギー7.289 eV．イオン半径は，Bi^3＋(六配位)0.117 nm，Bi^5＋(六配位)0.090 nm．Bi^3＋/Biの標準電極電位は＋0.32 V で，イオン化傾向は小さい．すべての元素のなかでもっとも反磁性が強く熱伝導率は水銀についで金属中最少である．またビスマスはガリウム同様液体から固化すると，体積が増加(3.5％)する数少ない金属の一つである．酸化力のない酸には溶けないが，硝酸，王水などに溶解し，ビスマス(Ⅲ)塩を生じる．空気中では，高温では燃焼しBi₂O₃となる．ハロゲンと反応し，BiCl₃(白色)，BiBr₃(黄金色)，BiI₃(緑黒色)，BiF₅を生じる．化合物は，酸化数3が通常であるが，酸化数5の化合物は強酸化剤である(例：M^ⅠBiO₃)．
無鉛はんだ，スプリンクラー用温度ヒューズなどに用いられる易融金属．おもな用途は，冶金添加剤，鉄鋼の機械加工性改良用添加剤，磁石・メモリー用フェライト，低融点合金用など．抗菌剤，医薬品(制酸剤など)，石油化学用触媒などにも用いられる．新しい用途には，光記録(CD-R，CD-RW)媒体，光磁気記録(MD，MO)用保護膜用材料がある．高温超伝導体(ビスマス系)の成分としても知られている．[CAS 7440-69-9][別用語参照]ビスマス化合物

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