Quiz 5 Alternative Assignment Quiz 5 will be replaced by a class project to assemble so facts about some of the elements. Each of you have chosen an element. You are to look up some facts about the element, and send me a PowerPoint file with data about the element: 1)Source of the element. For metals usually an ore. For non-metals various sources 2)The formula of the most common chlorides, oxides, and hydridse (if any). Pick one of these compounds and describe the type of compound: ionic, network covalent, or molecular. Include structural information if one of the simple ionic or molecular structures we have studied. 3)Two uses of the element or compounds of the element: industrial, commercial, or biological 4)Two interesting facts about the element or compound of the element not used in #3. This could be an interesting physical property, a story of how the element was discovered, the etymology of it name, or something else you find interesting. 5)Your information should be placed on two to three PowerPoint slides. 6)You must include one properly formatted and balanced chemical reaction in your slides. 7)We are not meeting in May because the Tuesday = Friday on May 2 nd. The assignment id due April 30. You have until midnight. Sunday and Monday, I will assemble them and post the combined file to the class webpage. You will review the file because I will pick material from element Z =1-18 for one question and material from the higher elements for another question on the final. 8)Sources: You should be able to find all the information you need in your text. I also recommend Webelements. The tabs “essentials”, “uses”, “compounds”, and “biology” should be useful. If you use other sources make sure they are reliable. Wikipedia should be confirmed by another source. Webelements 9)The format I want is on the next two slides. The assignment will be graded for accuracy, completeness, and format. Good Luck and enjoy yourself.

Tungsten (W) Z = 74, Period = 6, Group = 6. Source : Tungsten is found in as the tungstate ion WO 4 2- in the minerals scheelite CaWO 4 and wolframite (Fe or Mn)WO 4 Binary Compounds: – Chlorides: WCl 2, WCl 4, WCl 6, W 2 Cl 10, [W 6 Cl 12 ]Cl 6 – Oxides: WO 2, WO 3 – Hydrides: none Highlighted compound – WCl 6 is a molecular octahedral compound that melts at 275°C. It is prepared by direct chlorination of W. – W(s) + 3Cl 2 (g) WCl 6 (s)

Tungsten (cont.) Uses – Tungsten bronzes are non-stoichiometric compounds of formula Na x WO 3 (x = 0.3 to 0.9) which have metallic appearances and varied colors from blue to golden. They are used in paints. – tungsten and its alloys are used extensively for filaments for electric lamps, electron and television tubes, and for metal evaporation work Interesting Facts – Tungsten has the highest melting point (3422 °C) and 2 nd highest boiling point (5555 °C) of all the metals. (Re is 5869 °C) – Certain bacteria that live at 100 °C substitute W for Mo in enzymes probably because of the greater stability of the W- ligand bond strength.