1 For a 2-hour party, Cork Catering in Illinois charges $7.50 per guest for beer or wine only and $14.50 per guest for a premium bar serving most types of mixed drinks. 2  For detailed open bar pricing, see How Much Does an Open Bar Cost. For a 2-hour party, Cork Catering in Illinois charges $7.50 per guest for beer or wine only and $14.50 per guest for a premium bar serving most types of mixed drinks. 2  For detailed open bar pricing, see How Much Does an Open Bar Cost.
Selenium exists in a number of allotropic forms. Allotropes are forms of an element with different physical and chemical properties. One allotrope of selenium is an amorphous red powder. A lump of clay is an example of an amorphous material. A second allotrope of selenium has a bluish, metallic appearance.
Selenium is a chemical element with symbol Se and atomic number 34. It is a nonmetal with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. It rarely occurs in its elemental state or as pure ore compounds in the Earth's crust. Selenium was discovered in 1817 by JÃ¶ns Jacob Berzelius, who noted the similarity of the new element to the previously discovered tellurium. Selenium is found in ...