States of Matter. BUILDING BIG: Home Page. Explore large structures and what it takes to build them with BUILDING BIG™, a five-part PBS television series and Web site from WGBH Boston. Here are the main features of the site: Bridges, Domes, Skyscrapers, Dams, and Tunnels. The Labs Try your hand at our interactive engineering labs. The Challenges Take on the challenges of building big. Wonders of the World Databank Explore our databank of big structures. Local Wonders Investigate big structures near you. Who Builds Big? About the Series Learn more about the shows, and see a chat with David Macaulay. Educators' Guide How to use the Web site, with hands-on activities. Shop Building Big DVDs and books from David Macaulay available at ShopPBS.org. Site Tour Learn more about the features in this site. Site Map The whole site at a glance. Web Credits Feedback Help. S-Cool | Chemistry. REACTIONS. What is a chemical reaction? Examples of chemical changes, physical changes, and some gray areas.
Chemical equations of chemical reactions.Balancing equations. Balancing ionic equations with polyatomic ions. Balancing combustion (burning) equations. Balancing by overview. A chemical reaction is material changing from a beginning mass to a resulting substance. A chemical equation is a way to describe what goes on in a chemical reaction, the actual change in a material.
Back to the top of Reactions. Chemical reactions, also called chemical changes, are not limited to happening in a chemistry lab. A silver spoon tarnishes. Ag2S An iron bar rusts. 2 Fe2O3 Methane burns. An antacid (calcium hydroxide) neutralizes stomach acid (hydrochloric acid). CaCl2 + 2 H2O Glucose (simple sugar) ferments to ethyl alcohol and carbon dioxide. 2 C2H5OH (ethyl alcohol) + 2 CO2 Alcohol plus oxygen becomes vinegar and a molecule of water. Here are some examples of changes that are NOT chemical reactions. Easy. Or. GCSE Bitesize - Atoms, metals, rocks and fuel.