W was the 19th letter and was pronounced "wah"; there was an equivalent letter in the old Baybayin script of the Philippines. In the International Phonetic Alphabet, is used for the voiced labial-velar approximant. W is the symbol for the chemical element tungsten, after its German (and alternative English) name, "Wolfram". It is also the SI symbol for the watt, the standard unit of power. Double-u, whose name reflects stages in the letter's evolution when it was considered two of the same letter, a double U, is the only modern English letter whose name has more than one syllable. It is
Gallium highly reactive (rubidium and caesium) nor highly toxic (mercury) and can therefore be used in metal-in-glass high-temperature thermometers. It is also notable for having one of the largest liquid ranges for a metal, and for having (unlike mercury) a low vapor pressure at high temperatures. Gallium's boiling point, 2673 K, is more than eight times higher than its melting point on the absolute scale, the greatest ratio between melting point and boiling point of any element. Unlike mercury, liquid gallium metal wets glass and skin, along with most other materials (with the exceptions of quartz, graphite, and Teflon), making it