M3C  = See also:

• MANGANESE (symbol Mn; atomic weight, 54.93 (0=16)], a metallic chemical element. Its dioxide (pyrolusite)

manganese, See also:

• IRON [symbol Fe, atomic weight 55.85 (0=16)]

iron ; M2C = See also:

• MOLYBDENUM [symbol, Mo; atomic weight, 96 (0=16)]

molybdenum ; M3C2= See also:

• CHROMIUM (symbol Cr. atomic weight 52.1)

chromium ; MC = See also:

• ZIRCONIUM

zirconium ; M4C3 = See also:

• BERYLLIUM

beryllium, See also:

• ALUMINIUM (symbol Al; atomic weight 27.0)

aluminium ; M2C3 = See also:

• URANIUM [symbol U, atomic weight 238.5 (0=16)]

uranium; MC2 = See also:

• BARIUM (symbol Ba, atomic weight 137'37 [0=16])

barium, See also:

• CALCIUM [symbol Ca, atomic weight 40.0 (o= x6)]

calcium, See also:

• STRONTIUM [Symbol Sr, atomic weight 87.62 (0=16)]

strontium, See also:

• LITHIUM [symbol Li, atomic weight 7•oo (0=16)]

lithium, See also:

• THORIUM (symbol Th, atomic weight ,232.42 [0=16])

thorium, &c.; M C4 = chromium . The See also:

• PRINCIPAL

principal methods for the preparation of carbides may be classified as follows:—(1) See also:

• DIRECT

direct See also:

• UNION
• UNION (known locally as Union Hill and officially as Town of Union)

union at a high temperature, e.g. lithium, iron, chromium, See also:

• TUNGSTEN [symbol W, atomic weight 184.o (0=16)]

tungsten, &c.; (2) by the reduction of oxides with See also:

• CARBON (symbol C, atomic weight 12)

carbon at high temperatures, e.g. calcium, barium, strontium, manganese, chromium, &c.; (3) by the reduction of See also:

• CARBONATES

carbonates with See also:

• MAGNESIUM [symbol Mg, atomic weight 24.32 (0 = 16)]

magnesium in the presence of carbon, e.g. calcium, lithium; (4) by the See also:

• ACTION

action of metals on See also:

• ACETYLENE

acetylene or metallic derivatives of acetylene, e.g., See also:

• SODIUM [symbol Na, from Lat. natrium; atomic weight 23.00 (0=16)]

sodium, See also:

• POTASSIUM [symbol K (from kalium), atomic weight 39.114 0=16)]

potassium . The metallic carbides are crystalline solids, the greater number being decomposed by See also:

• WATER

water into a metallic See also:

• HYDRATE

hydrate and a hydro-carbon; sometimes See also:

• HYDROGEN [symbol H, atomic weight x-oo8 (0=16)]

hydrogen is also evolved . Calcium See also:

• CARBIDE

carbide owes its See also:

• INDUSTRIAL

industrial importance to its decomposition into acetylene; lithium carbide behaves similarly . Methane is yielded by aluminium and beryllium carbides, and, mixed with hydrogen, by manganese carbide . The important carbides are mentioned in the See also:

• SEPARATE

separate articles on the various metals . The commercial aspect of calcium carbide is treated in the See also:

• ARTICLE (from Lat. articulus, a joint)

article ACETYLENE .