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Bronze disease. Bronze disease is an irreversible and nearly inexorable corrosion process that occurs when chlorides come into contact with bronze or other copper-bearing alloys. [1] It can occur as both a dark green coating, or as a much lighter whitish fuzzy or furry green coating. [1] It is not a bacterial infection, but the result of a ...
Thermite (/ ˈθɜːrmaɪt /) [ 1 ] is a pyrotechnic composition of metal powder and metal oxide. When ignited by heat or chemical reaction, thermite undergoes an exothermic reduction-oxidation (redox) reaction. Most varieties are not explosive, but can create brief bursts of heat and high temperature in a small area.
Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals, such as phosphorus, or metalloids, such as arsenic or silicon. These additions produce a range of alloys that may be harder than copper ...
Phases of ice. hide. Log-lin pressure-temperature phase diagram of water. The Roman numerals correspond to some ice phases listed below. The phases of ice are all possible states of matter for water as a solid. Variations in pressure and temperature give rise to different phases, which have varying properties and molecular geometries.
Surface rust is commonly flaky and friable, and provides no passivational protection to the underlying iron, unlike the formation of patina on copper surfaces. Rusting is the common term for corrosion of elemental iron and its alloys such as steel. Many other metals undergo similar corrosion, but the resulting oxides are not commonly called ...
Tarnish is a product of a chemical reaction between a metal and a nonmetal compound, especially oxygen and sulfur dioxide. It is usually a metal oxide, the product of oxidation; sometimes it is a metal sulfide. The metal oxide sometimes reacts with water to make the hydroxide, or with carbon dioxide to make the carbonate. It is a chemical change.
Passivation involves creation of an outer layer of shield material that is applied as a microcoating, created by chemical reaction with the base material, or allowed to build by spontaneous oxidation in the air. As a technique, passivation is the use of a light coat of a protective material, such as metal oxide, to create a shield against ...
Roman silver ingot, Britain, 1st–4th centuries AD. Lead ingots from Roman Britain. Metals and metal working had been known to the people of modern Italy since the Bronze Age. By 53 BC, Rome had expanded to control an immense expanse of the Mediterranean. This included Italy and its islands, Spain, Macedonia, Africa, Asia Minor, Syria and ...