Alkaline rock, any of various rocks in which the chemical content of the alkalies (potassium oxide and sodium oxide) is great enough for alkaline minerals to form.
Glass, glazes, and enamel (but not faience) contain high amounts of alkali, such as sodium oxide (soda glass) or potassium oxide (potash glass).
By adding about 25 percent of the sodium oxide to silica, the melting point is reduced from 1,723 to 850 °C (3,133 to 1,562 °F).
In order to effect this reduction, much of the sodium oxide added as a flux is replaced by boric oxide (B2O3) and some of the lime by alumina.
It is composed of about 70 percent silica (silicon dioxide), 15 percent soda (sodium oxide), and 9 percent lime (calcium oxide), with much smaller amounts of various other compounds.
Water glass, also called sodium silicate or soluble glass, a compound containing sodium oxide (Na2O) and silica (silicon dioxide, SiO2) that forms a glassy solid with the very useful property of being soluble in water.
To reduce the melting point of silica, it is necessary to add a flux; this is the purpose of the sodium carbonate (soda ash), which makes available the fluxing agent sodium oxide.
Sodium carbonate was decomposed into sodium oxide in 1017 K.
Sodium oxide is the least dense compound in soda-lime glass.
The composition of these nanotips has been investigated and shown to be primarily sodium oxide.
After that, sodium oxide was cooled down and adsorbed on the surface of coke.
