silicon oxygen compounds
111Protactinium — thorium ← protactinium → uranium Pr ↑ Pa ↓ …
112chromium processing — Introduction preparation of the ore for use in various products. Chromium (Cr) is a brilliant, hard, refractory metal that melts at 1,857° C (3,375° F) and boils at 2,672° C (4,842° F). In the pure state, it is resistant to ordinary… …
113Argon — This article pertains to the chemical element. For other uses, see Argon (disambiguation). Argon (pronEng|ˈɑrgɒn) is a chemical element designated by the symbol Ar. Argon has atomic number 18 and is the third element in group 18 of the periodic… …
114aluminum — aluminic /al yeuh min ik/, adj. /euh looh meuh neuhm/, n. 1. Chem. a silver white metallic element, light in weight, ductile, malleable, and not readily corroded or tarnished, occurring combined in nature in igneous rock, shale, clay, and most… …
115lead processing — Introduction preparation of the ore for use in various products. Lead (Pb) is one of the oldest metals known, being one of seven metals used in the ancient world (the others are gold, silver, copper, iron, tin, and mercury). Its low… …
116Extraterrestrial life — For fiction, see Extraterrestrials in fiction. For other uses, see Alien (disambiguation). A 1967 Soviet Union 16 kopeks postage stamp, depicting a satellite from an imagined extraterrestrial civilization …
117Sodium — This article is about the chemical element. For the PlayStation Home game, see Sodium (PlayStation Home). neon ← sodium → magnesium Li ↑ Na ↓ K …
118Selenium — (pronEng|səˈliniəm) is a chemical element with the atomic number 34, represented by the chemical symbol Se, an atomic mass of 78.96. It is a nonmetal, chemically related to sulfur and tellurium, and rarely occurs in its elemental state in nature …
119Space colonization — Artist Les Bossinas 1989 concept of Mars mission Space colonization (also called space settlement, space humanization, or space habitation) is the concept of permanent human habitation outside of Earth. Although hypothetical at the present time,… …
120star — starless, adj. /stahr/, n., adj., v., starred, starring. n. 1. any of the heavenly bodies, except the moon, appearing as fixed luminous points in the sky at night. 2. Astron. any of the large, self luminous, heavenly bodies, as the sun, Polaris,… …
