What is the difference between bismuth and bismuth oxide?

Bismuth metal characteristics

Element type: Metal

Crystal structure: The cell is triclinic.

At room temperature, bismuth does not react with oxygen or water, but is stable in air. When heated above the melting point, it can burn and emit a light blue flame to form bismuth trioxide. Bismuth can also be combined with sulfur and halogen at red heat. Bismuth is insoluble in water. It is insoluble in non-oxidizing acids, such as hydrochloric acid. Even concentrated sulfuric and hydrochloric acids react only slightly on co-heating, but are soluble in aqua rega and concentrated nitric acid. The + 5-valent compound NaBiO5 (sodium bismuth) is a strong oxidant used in analytical chemistry to detect Mn.

Source of pure bismuth

Bismuth occurs in nature as a free metal and mineral. Minerals are bismuth ore, bismuth wah, etc. Bismuth is obtained by calcination of minerals into bismuth trioxide, and then by co-thermal reduction with carbon. High purity bismuth can be obtained by fire refining and electrolytic refining.

Application of Bismuth

Bismuth is mainly used in the manufacture of fusible alloys, whose melting point ranges from 47 ℃ to 262℃. Bismuth is most commonly used as an alloy composed of lead, tin, antimony, indium and other metals, which is used in fire-fighting devices, automatic sprinkler and boiler safety plugs. In case of fire, the pistons of some water pipes will "automatically" melt and spray water. In fire and electrical industry, used as automatic fire extinguishing system and electrical fuse, solder. Bismuth alloys are used for printing type and high precision casting because they do not shrink during solidification. Bismuth oxycarbonate and bismuth oxynitrate are used to treat skin lesions and gastroenteric diseases.

Bismuth oxide basics

Sub-type: Bi2O3

Sub-volume: 465.96

Melting point: 825 ℃

Solubility: INSOLUBLE

Bismuth oxide powder properties

Yellow heavy powder or monoclinic crystal. No smell. It's stable in the air. Soluble in hydrochloric acid and nitric acid; It is almost insoluble in water and turns maroon when heated and yellow when cold. Relative density 8.5. The melting point is 820℃, and the boiling point is 1890℃.

Bismuth oxide granules application

Used as an analytical reagent. Prepared with bismuth salt. Manufacture of fire-proof paper. The bisMUth oxide can be widely used in inorganic synthesis, electronic ceramics, chemical reagents and other fields, mainly for the manufacture of ceramic dielectric vessels, and also for the manufacture of piezoelectric ceramics, varistors and other electronic ceramic components.

The toxicity of bismuth

1) Most compounds, especially the salt base salts, are difficult to absorb in the digestive tract. Insoluble in water, only slightly soluble in tissue fluid. It cannot be absorbed through intact skin and mucosa. After absorption, bismuth is distributed throughout the body, most of which is the kidney, followed by the liver. Most of the bismuth stored in the body is excreted in urine within weeks or months.

2) Bismuth metabolizes similarly to lead in the body. In acidosis, the tissue releases the accumulated bismuth. Bismuth and lead may interact. In vivo, bismuth compounds can form bismuth sulfide, which is insoluble in water and dilute acid, precipitate in tissues or embolize in capillaries, resulting in local ulceration and even necrosis. Under the action of intestinal bacteria, bismuth nitrate can be reduced to bismuth nitrite, which causes methemoglobinemia after absorption. In severe chronic intoxication, because bismuth is mostly present in the kidney, severe nephritis may occur, especially in renal tubular epithelial cells, and the liver may also be involved. "Bismuth line" may appear in patients with repeated oral or other chronic poisoning.

No occupational poisoning caused by inhalation of bismuth and its compounds was observed. Chronic intoxication is mainly caused by drugs containing soluble bismuth salts.

3) People with skin injury should avoid direct contact with soluble bismuth salt. Sodium dimercaptopropanesulfonic acid can be used as an antidote.