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Tin pest. Tin medal affected by tin pest. Tin pest is an autocatalytic, allotropic transformation of the element tin, which causes deterioration of tin objects at low temperatures. Tin pest has also been called tin disease, [1] tin blight, tin plague, [2] or tin leprosy. [3] It is an autocatalytic process, accelerating once it begins.
Tin. Tin is a chemical element; it has symbol Sn (from Latin stannum) and atomic number 50. A silvery-colored metal, tin is soft enough to be cut with little force, [10] and a bar of tin can be bent by hand with little effort. When bent, the so-called "tin cry" can be heard as a result of twinning in tin crystals. [11]
Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure.. Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other' and τρόπος (tropos) 'manner, form') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.
These allotropes are known as the amorphous and the crystalline allotropes. The amorphous allotrope is a brown powder. The crystalline allotrope is gray and has a metallic luster. [16] Tin has two allotropes: α-tin, also known as gray tin, and β-tin. Tin is typically found in the β-tin form, a silvery metal.
Tin (IV) oxide, also known as stannic oxide, is the inorganic compound with the formula SnO2. The mineral form of SnO 2 is called cassiterite, and this is the main ore of tin. [9] With many other names, this oxide of tin is an important material in tin chemistry. It is a colourless, diamagnetic, amphoteric solid.
Infobox references. Tin (II) oxide (stannous oxide) is a compound with the formula SnO. It is composed of tin and oxygen where tin has the oxidation state of +2. There are two forms, a stable blue-black form and a metastable red form.
These tetrahedrons together form a 3-dimensional network of six-membered carbon rings in the chair conformation, allowing for zero bond angle strain. The bonding occurs through sp 3 hybridized orbitals to give a C-C bond length of 154 pm. This network of unstrained covalent bonds makes diamond extremely strong.
A urine test strip or dipstick is a basic diagnostic tool used to determine pathological changes in a patient's urine in standard urinalysis. [1] A standard urine test strip may comprise up to 10 different chemical pads or reagents which react (change color) when immersed in, and then removed from, a urine sample.