Silicon

Silicon
An Internet Hotlist on Silicon

created by dylantomalin10

Introduction | Basic Information | Health | Uses | Silicon Tetrachloride

Introduction

image from http://www.galleries.com/minerals/elements/silicon/silicon.jpg>

Symbol: Si,
Atomic Number: 14.
Atomic Mass: 28.0855 amu.
Classification: Metalloid.
Physical Characteristics: Crystal Structure- Cubic, Color- Gray.
Melting Point: 1410 degrees C.
Boiling Point: 3265 degrees C.
Isotopes: 5.
Toxicity: Silicon Tetrachloride is incompatible with water, acids, bases, alcohols, alkali metals, organics and powdered metals. It may cause burns and is harmful if swallowed or inhaled.
Uses: Surgical Implants, semiconductors, glass making, bricks and concrete, dietary silicon can help reduce bone mineral density.
Production: Found in the earth's crust.
History: Jöns Jacob Berzelius of Sweden in 1824 by heating up chips of potassium in a silica container and then washing away the residual by-products.\
My rating system is in bra size. The bigger the bra size, the better the website is.

The Internet Resources

Basic Information

American Elements - This site has a lot of detailed basic information about Silicon. It makes up 25.7% of the earth's crust by weight. It is the second most abundant element after Oxygen. Silicon is a Block D, Group 14, Period 3 element. Silicon was first discovered by Jons Berzelius in 1823. 36B.
Environmental Chemisty- Silicon - This site has at least 20 links to other Silicon related information. It contains an Overview of Silicon, the Atomic Structure of Silicon, Chemical Properties of Silicon etc. Also Nuclides and Isotopes. This site also has the names of Silicon in other languages; (Croatian: Silicij, French: Siliciu, Swedish: Kisel). This site has any information you would ever want to know about the element. 36DD.
Jefferson Lab - This site has a lot of the basic facts. It includes facts such as the Atomic Weight (28.0855), the Melting Point (2577°F), the Boiling Point (5909°F), the Phase at Room Temperature (Solid), the Element Classification (Semi-metal). This site also includes some of the history of the element. Silicon was discovered by a Swedish chemist, Jöns Jacob Berzelius, in 1824 by heating up chips of potassium in a silica container and then washing away the residual by-products. I would rate this website a 36C.
Mineral Information Institution - Silicon is an element that is essential to plant and animal life. It was discovered to 1824. Silicon was discovered by Jons Jakob Berzelius of Sweden. It is a shiny blue-gray metallic substance. It looks like a metal. In the form of Silica it is the second-most common element in the Earth's crust. Pure silicon is never found in nature. There are hundreds of silicon-bearing minerals. 36B
Periodic Table of the Elements - This site has basic information including the Atomic Number (14), Atomic Symbol (Si) and Atomic Weight (28.086). There is a section on the Sources of Silicon. Silicon is in the sun and the stars. Silicon makes up 25.7% of the earth's crust. This site also details some of the many uses of Silicon. In the form of sand and clay it is used to make concrete and brick. There is also a small section on the costs of Silicon. Regular grade silicon (99%) costs about $0.50/g. Silicon 99.9% pure costs about $50/lb. Hyperpure silicon can cost as much as $100/oz. I would rate this site a 36B.
Periodic Table: Silicon - This website is all about basic information. It tells the number of Protons (14), number of Electrons (14), number of Neutrons (14, its Classification (Metalloid), its Crystal Structure (Cubic), its Color (Grey) and much more. There is also a picture of the Atomic Structure. There are 3 Energy Levels. It also gives a short description of its history. Date of Discovery (1823), Name of Origin (From the Latin word silex. This website is short, so I would only rate it a 36A.
Silicon - This site does a great job demonstrating some of the many uses of Silicon. It is used to make concrete and brink. Hydrogenated amorphous silicon has shown chances in making economical cells for converting solar energy into electricity. Silicon also plays a big role in plant and animal life. Silicon is found in the ashes of plans and the human skeleton. 38C.
Visual Elements Silicon - This site has a main page, with a link leading to its other page. The home page has a brief summary of basic information including who discovered the element and when (J.J. Berzelius in 1824). The html link has a picture of Silicon and goes into more details about the discovery (discovered in Sweden). Its Appearance (bown powerder), Uses (concrete and cement), Biological Role (essential to plant and animal life). This site has tons of useful information. I would rate it a 34D.
Web Elements Silicon - This website has all the basic information about Silicon. It has the essentials such as the periodic table symbol and atomic number. The period table symbol of Silicon is Si. The atomic number is 14. There is also a short summary of the isolation of Silicon. There is also a comic called 'Analytical Chemists as Book Reviewers'. I would rate this website a 38B.

Health

Just Breast Implants - This site has the FDA approval of Silicon implants. There is everything you need to know about Silicon breast implants. Silicon implants have three layers of shell surrounding the silicon gel. This thicker shell reduces the amount of gel bleed, but also makes the implants firmer. Silicon breast implants come pre-filled, which means that the incision has to be longer. 36B

Uses

Beverage - This site is about the benefits of Silicon found in beer. Researchers found that the silicon content in beer varied from 9 to 39 mg per liter. The amount of Silicon in beer varies in the way that malted barley is processed. Beer contains the highest source of silicon per serving because its makers use the husks of the grain where the silicon is. Dietary silicon can help reduce bone mineral density. 34C.
How Semiconductors Work - Semiconductors have a big impact on our society. Anything that is computerized or uses radio waves depends on semiconductors. Most semiconductor chips and transistors are created with silicon. Metals are good conductors of electricity because they usually have 'free electrons' that can move between atoms easily, and electricity involves the flow of electrons. The outer electrons in a silicon crystal are involved in perfect covalent binds so they can not move around. Pure silicon crystal in an insulator so very little elctricity can flow through it. This site has everything you need to know about Semiconductors and explains it in a way that easy to understand. 36C.
Meteorites Reveal Earth's Core - This site has an article about an Silicon and it's relation to the core of planets. An international team led by Alex Halliday (Oxford University) team looked for Silicon's 3 stable isotopes with masses of 28. 29, and 30. They found out that meteorites from Mars and a large asteroid (Vesta) have higher proportions of light silicon with mass 28. This team concluded that the mass difference was caused during core formation. This article also states that the silicon composition of the Earth is the same as the moon's. 38B.

Silicon Tetrachloride

Safety Data for Silicon Tetrachloride - Silicon Tetrachloride is a light yellow fuming liquid. It is moisture sensitive meaning that it reacts violently with water. Silicon Tetrachloride is incompatible with many things including water, acids, bases, alcohols, alkali metals, organics and powdered metals. It may cause burns and is harmful if swallowed or inhaled. It can also cause skin and eye irritation. Personal protection around Silicon Tetrachloride would mean wearing safety glasses, gloves, and having good ventilation.
Silicon Tetrachloride - This site does not contain a lot of information but it does have the basics. Silicon Tetrachloride (SiCl4) is colorless, toxic and nonflammable. Applications of Silicon Tetrachloride (plasma etching of metals). Materials Compatibility (Stainless Steel, Carbon Steel, Monel). Molecular Weight (169.90). The smell of Silicon Tetrachloride is pungent and suffocating. 36B.

Content by dylantomalin10, dtomalin@sbschool.org
http://www.kn.att.com/wired/fil/pages/listsilicondy.html
Last revised Mon Dec 17 7:38:03 US/Pacific 2007