Unit 2 Chemical Reactions and Radioactivity

Chapter 4 Resources

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Methane Hydrate - this source of methane is found trapped in ice at the bottom of ocean trenches:

• Fire and Ice - Dr. Ross Chapman's school, the University of Victoria, profiles the researchers work in this field. You can find the original announcement of the 2002 discovery at this link.
• Methane Hydrates - information about this intriguing potential fuel source, and world locations of the resource.
• Energy Source of the Future? - Popular Science outlines this promising discovery.

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Mining Methane - - The Mallik 2002 drilling program explored buried deposits of methane, trapped under high pressure and low temperature in tiny ice cages. While we know there's a lot of this material - perhaps as much as the entire world's reserves of traditional fossil fuels - there is also not a lot known about it. In this 9 minute audio Quirks and Quarks broadcast, Scott Dallimore, the lead principal investigator with the Mallik 2002 Gas Hydrate Well Program, and a research scientist with the Geological Survey of Canada, says their experiments show that these deposits may indeed be suitable for commercial extraction. (Tip: Download audio files to your hard drive by right-clicking and choosing "Save Link As...")

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Calcium Metal in Water - this includes a short description of the procedure and a 0:58 video clip of the reaction. (RealPlayer required)

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Atomic Theory and the Nucleus - the atom, once thought to be indivisible, is actually made up of sub-atomic particles:

• Scale Model of a Hydrogen Atom - It can be difficult to believe, but even the smallest atoms - here, hydrogen - are composed primarily of empty space.
• Atoms Around Us - the Chem4Kids site runs through atomic structure, ions, isotopes, compounds and more, and asks interactive questions along the way. This is a great preview/review for this chapter.
• The Particle Adventure - a review of atomic theory, with interesting trivia and questions.
• Matter! - a nice interactive tutorial with good visuals of the atom.

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The Periodic Table - the organization and data of the periodic table:

• ChemicalElements.com - almost everything you might want to know about the elements of the periodic table are just a click away.
• WebElements periodic table - the original online periodic table, with in-depth information on all of your favourite elements.
• Origins of the Periodic Table - this guide reviews many of the topics in the atomic theory and periodic table.

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The Bohr Model of the Atom - Bohr models of atoms show the nucleus, its contents and the electron shells:

• Atomic Structure - a quick review of the atom, and then a discussion of the Bohr model.
• Whizzy Periodic Table - showing the electron energy shells for the lighter elements.
• Bohr's Atom - a more advanced look at the atom from a quantum perspective, shown as a Bohr model.
• How Do I Make a Model of an Atom? - a step-by-step guide to each portion of the Bohr atom.

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The Lewis Model of the Atom - using a simplified atomic structure for easy, accurate diagrams of chemical bonding:

• Lewis Diagrams of the Atom - a simplified version of Bohr models that only show valence electrons and chemical symbols.
• Lewis Structures - this guide takes you through writing a Lewis structure, as well as ionic and covalent compounds as Lewis diagrams.

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Ozone - this important molecule is our first line of defense against harmful ultraviolet radiation from the sun:

• The Ozone Resource Page - NASA provides in-depth information about ozone and the ozone layer.
• Good Up High, Bad Nearby - a thorough explanation of ozone
• Lewis Diagram of Ozone - more in-depth than we cover in this course, but it is interesting to see all the work that goes in to a complete Lewis diagram.

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SciSat/ACE Satellite - - While big NASA and ESA missions get most of the attention, the Canadian space program is making big gains with modest projects. Introduced in this 8 minute audio Quirks and Quarks broadcast, the SciSat/ACE satellite is a great example. It's a $42-million-dollar ozone observatory that's studying the Arctic atmosphere to understand the chemical processes contributing to the hole in the ozone layer.

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Nanotechnology - extremely tiny items, often just a few atoms in size, are made for a variety of purposes.

• Nanotechnology Now - a collection of nano-news.
• How Nanotechnology Works - a nice look at the background of the science, including a short 2:00 video.
• Center for Responsible Nanotechnology - this site shows recent nanotechnology developments, as well as discussing where this technology may lead us.

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Atomic Theory and Bonding - try this puzzle to test your knowledge about bonding. (Also available for download )

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Section 4.1 Quiz - need more practice? Try this online quiz.

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Ionic compound crystal formation - the positive and negative interactions in an ionic compound produce regular, crystalline solids.

• Ionic Structure - illustrating and explaining the formation of ionic compounds as crystals.
• Formation of Ionic Crystal - this simulation shows the positive and negative particles settling into (hopefully) a regular crystalline pattern. If a crystal doesn't form, just tweak the charges and wait for the result.

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Ionic Compound Names and Chemical Formulas - the transfer of electrons between a cation (positive ion) and anion (negative ion).

• Naming Ionic Compounds - how to name the transfer of electrons between cations (metallic ions, ammonium polyatomic ion) and anions (non-metallic ions, negative polyatomic ions).
• Formulas to Names - use this quiz page to test how well you can name ionic compounds based on their chemical formulas.
• Names to Formulas - use this quiz page to test how well you can write chemical formulas of ionic compounds based on their name.
• Names and Formulas - this java-based quiz is simple, but provides lots of practice naming ionic compounds.
• Ionic Nomenclature - more practice with the names and formulas of ionic compounds.

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Covalent Compound Names and Chemical Formulas - the sharing of electrons between non-metals in a variety of proportions.

• All About Covalent Compounds - naming, formulas and even properties of covalent compounds.
• Naming Covalent Compounds - the basics of covalent names and formulas.
• Comparing Ionic and Covalent Bonding - a good summary of both bond types.

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Practical Uses of Various Compounds - sometimes we forget; these formulas and names are attached to some interesting chemicals.

• FeCl₃ - iron (III) chloride, aka ferric chloride, is used to improve water quality, etch memory boards for electronics, and is involved in the process of making PVC plastics.
• CuSO₄ - copper (II) sulfate, is used as a pesticide, in biochemistry labs for identifying sugars or proteins, and even in places like hair dyes, baby formula and fireworks.
• ZnO - zinc oxide, is used in cough lozenges, in breakfast cereals as a source of zinc, as a whitening compound in paints and sunscreens, in the manufacture of many rubber products, and in electronic devices like LED lights.

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Flame Test - ionic compounds burn in very distinct colours, all at once.

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Electronegativity - electrons are shifted around in molecules, causing parts to become polar (slightly more negative or positive).

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Names and Formulas - this puzzle reviews naming of compounds. (Also available for download )

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Section 4.2 Quiz - need more practice? Try this online quiz.

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Early Earth Air - - Titan, one of Saturn's moons, has an atmosphere of methane and nitrogen. Sunlight breaks this atmosphere down into complex hydrocarbons -- basically smog particles -- which rain down on the surface. If all this reminds you of Earth, then you live in Los Angeles, or your memories are of a time about 3 billion years ago. In this 8 minute audio Quirks and Quarks broadcast, a research team from the University of Colorado shows that the early Earth's atmosphere could well have been much like Titan's, and the pollution-like chemicals created from the methane could have been a tasty treat for early microbial life.

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Chemical Equations - this puzzle reviews chemical equations - give it a try. (Also available for download )

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Copper and Nitric Acid - these two react very vigorously.

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Chemical Equations - each of these methods helps to explain and examine the atoms involved in chemical change.

• Chemistry Word Equations - a simple set of examples illustrating how to get from a word equation to a balanced chemical equation.
• Writing Word Equations - once the word equation is written, the remaining steps to obtain a balanced reaction are covered as well.

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Ignite Hydrogen in a Balloon - but what if the balloon was really big?

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Mass Changes in Chemical Reactions - although there are chemical changes, and therefore different materials produced, the overall mass in the system stays the same.

• The Law of Conservation of Mass - matter cannot be created or destroyed, but can be rearranged.

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Law of Conservation of Mass Experiment - NaOH, CuSO₄, NH₄OH and Na₂CO₃ react. Is the mass of the products after the reaction the same as the reactants before you begin?

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Balancing Chemical Equations - since mass is equal before and after a chemical change, it makes sense that the numbers of atoms should also be the same before and after.

• Balancing Chemical Equations - tutorials, explanations and practice problems.
• Practice with Balancing Chemical Equations - use this site to practice your skills at balancing.

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Early Models of Chemical Compounds - amazing ideas sprang from the minds of the early chemists.

• History of the Molecule - early evidence of compounds caused some interesting theories to be proposed.
• Dalton's Atomic Theory - a biography of this important chemist.
• Chemical Compounds: History - a short history of the past 200 years in compound knowledge

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Antoine and Marie-Anne Lavoisier - these early brilliant chemists were among the first to grasp the concept of conservation of mass.

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Section 4.3 Quiz - need more practice? Try this online quiz.

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Chapter 5 Resources

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Pigments - the chemistry of the colours in our world:

• Pigments in Paintings - a history of how pigments have been used in paintings.
• Pigments: Their Historical, Chemical and Artistic Importance - a listing of popular pigments.

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The Tailless Whip Scorpion - which you may recognize from the Harry Potter movies as the victim of a cruciatus curse.

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Acids and Bases are Everywhere - information on acids, bases and the pH scale, the level of acidity is measured using this scale of 0 -14.

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Number Scales - there are many different scales used to measure and compare qualities in science:

• Geology and Earth Sciences - the geologic time scale (1 000 000 years per tick), and the Richter scale (a magnitude 6 earthquake has a magnitude 100 times greater than a magnitude 4 quake). A normal-sized globe, often found in a classroom, has a scale where 1 cm = 600 km. Tornado's are measured on the Fujita scale, where an F0 tornado breaks branches off trees, and an F4 lifts cars off the ground.
• Physical Sciences: Decibels - the decibel (dB) scale measure the intensity of sound (each increase of 10 dB = 10X louder). A rock concert or jet engine (120 dB) is 1 millions times louder than a normal conversation (60 dB).
• Physical Sciences: Light Years - In space, distances are so vast that light years are used. The distance between Earth and the sun is 1 micro-light year, while proxima centauri, the second-closest star to Earth, is 4 light years away.

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pH Indicators - a variety of devices, and chemicals, can be used to determine pH:

• Litmus Paper - one the simplest and best known methods of determining if a solution is acidic or basic.
• Chemical Indicators - a wide range of chemicals, measuring a wide range of pH values.
• pH Meter - a pH meter measures the precise amount of electricity that a solution can conduct, and displays the corresponding pH on a scale or digital screen

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Oceans and CO₂ - - Carbon dioxide emissions from industrial smokestacks and tailpipes doesn't just stay in the atmosphere. The CO2 is also absorbed into the world’s oceans, essentially acidifying the water. And that acid mix isn’t a healthy one for marine organisms. In this 8 minute audio Quirks and Quarks broadcast, Dr. Victoria Fabry of California State University at San Marcos spells out the danger our oceans face.

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Carbon Sunk In The Ocean - - Dr. Peter Brewer, Senior Scientist at the Monterey Bay Aquarium Research Institute, has been doing experiments on what happens to concentrated carbon dioxide when you put it deep underwater. In this 8 minute audio Quirks and Quarks broadcast, he describes experiments which might help to prove the practicality of dumping fossil fuel generated CO₂ in the deep ocean.

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Naming Acids - the name of the compound it comes from is key to naming an acid.

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Earth's Evil Twin - - 4.5 billion years ago, the Earth and Venus formed as virtual twins. Unfortunately, while Earth went on to life and glory, Venus went wrong. So it's now a world of crushing pressure, a runaway greenhouse effect, and sulfuric acid clouds. This 12 minute audio Quirks and Quarks broadcast describes the results from the European Space Agency's Venus Express mission that were recently released and they go some way toward explaining how Venus ended up as it did.

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pH Activities - there are many interesting, fun activities you can do with acids and bases, but always use proper safety precautions:

• Experiments with Acids and Bases - great review of acids and bases, plus some activities illustrating their unique properties.
• Kitchen Chemistry - have fun, and amaze your parents.
• Alien Juice Bar - if you're going to make juice for aliens, you had better understand pH!

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Bases - many bases have a chemical formula that ends with OH (but not all do)

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Acids, Bases and the Production of Ions - acids and bases are what they are because of the ions they produce when dissolved in solution:

• Acids, Bases and pH - the measurement of pH, and the strength of the acid or base, are dependent on ions.
• The pH Scale and Hydrogen Ion Concentration - short, simple explanation of the relationship between pH and hydrogen ion concentration.
• Acids, Bases and Ions - how ions relate to acids and bases.

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Insect Stings - Want to take the "sting" out of that insect bite? Use chemistry to help make your decision:

• Insect Stings - learn more about what you wish you knew less about.
• Formic Acid - named for the Latin word for ant, formica, this acid is also found in stinging nettles.

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Properties of Acids and Bases - take this 20-question quiz to test your knowledge of the properties of acids and bases.

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Lactic Acid - it turns out that lactic acid is actually used for added energy boosts for muscles, but it does increase the pH in the muscles as it is used.

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Acid Oceans - although it sounds good at first - oceans absorbing some of the excess carbon dioxide in the atmosphere - there is also more acid produced, dropping the pH of the ocean and changing many ocean ecosystems:

• Oceans Becoming More Acidic - the BBC reports on the changing ocean pH, and the effect on certain marine animals.
• Research Shows Oceans Becoming More Acidic - this UNESCO site also links to a major 2004 symposium on this topic.
• Impacts of Ocean Acidification - a 2006 study confirms earlier suspicions of decreasing pacific ocean pH.

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Calcium in the Cambrian - - 530 million years ago, in an event known as the Cambrian explosion, life went from simple and small to large and complex, and the animals that are ancestors to most creatures on earth suddenly appeared. In this 9 minute audio Quirks and Quarks broadcast, Dr. Tim Lowenstein, a professor of Geology at Binghamton University in New York State, found that the explosion of life corresponded to an increase in calcium in the sea. Animals used this extra calcium to build hard shells and structures that allowed them to get larger, and become more resistant to predators.

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Acids and Bases - test your acid and base knowledge with this puzzle. (Also available for download )

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Section 5.1 Quiz - need more practice? Try this online quiz.

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Salt - salt is a very complex compound, with a rich history:

• Salt Institute - discover more about salt in today's world, including the relationship between salt and the prevention of goiter.

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Three Salts - in our context, salts refer to the compounds formed during the reaction of an acid and a base:

• Acids, Bases and Salts - some review, and also includes a mention of oxides.
• Three Salts Experiment - Hydrochloric Acid and Zinc, Hydrochloric Acid and Sodium Carbonate, and Hydrochloric Acid and Magnesium Hydroxide.

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Acid-Base Neutralization - many household products, and everyday chemical reaction, rely on acid-base neutralization:

• Neutralization Reaction: Acids + Bases - including practical examples and labs.
• Acid/Base (Neutralization) Reactions - a review of the chemistry.
• Road Salts - government studies are attempting to balance safety and environmental concerns.

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Acid Rain - the oxides that produce acid rain, the effects of acid rain, and method to decrease oxide effects.

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Aluminum Amperage - - Cars and laptops of the future may run on -- aluminum. In this 8 minute audio Quirks and Quarks broadcast, we learn that aluminum normally reacts with water to form a kind of rust-like oxide. On most aluminum metal, this oxide forms an impermeable surface coating, protecting the rest of the aluminum from reacting. But Dr. Tom Troczynski, a professor of Ceramics and Dr. Ashok Chaklader, professor emeritus in the department of Materials Engineering at the University of British Columbia, have found that if you can remove this coating and expose the aluminum to water and salt, in just the right way, you release hydrogen. That hydrogen can be used to power a fuel cell for portable electronics or even for a car.

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Antimony: The New Lead - - Attempts to lower lead levels in the atmosphere have been very successful in the last few decades. But now, there's another metal out there, that has some scientists worried. It's antimony, a naturally occurring mineral, that's used in many different kinds of plastics. In this 8 minute audio Quirks and Quarks broadcast, Dr. Bill Shotyk, from the University of Heidelberg, has been measuring antimony levels in the Arctic. He's found that, while lead levels have been dropping, antimony levels are on the rise. He's also finding antimony oxide in water that has leached out of plastic bottles.

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Acids and Metals - the reaction of metals and acids was one of the original methods of classifying acidic solutions:

• Acids: Reaction with Metals - the salt produced depends on the metal reacting with the acid.
• Metals in Hydrochloric Acid - do this demo lab to discover how different metals react (or don't react) with HCl.

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Reaction of Metals with Acid - a complete virtual lab, taking you step-by-step through this topic.

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Acids and Carbonates - the reaction of metals and acids was one of the original methods of classifying acidic solutions:

• Using HCl to Identify Limestone - a drop of hydrochloric acid is an important tool for geologists identifying carbonates.
• Testing for the Presence of CO₂ - details of a limewater test, along with the theory of why this occurs.

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Acids and Carbonates - the reaction that threatens natural sources of carbonate via the production of acid precipitation:

• The Rubber Chicken and the Bouncing Egg - egg shells, a natural source of carbonates, change slightly when exposed to acetic acid.
• The Effect of Acid Rain on Marble Statues - conduct an experiment that simulates the reaction that alters statues and architecture.

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Protecting and Preserving Outdoor Art - acid precipitation threatens limestone statues and any architecture containing carbonates:

• Acid Rain - the effects of acid rain on ancient structures.
• Acid Rain Goes to Washington - a very thorough look at how acid rain is effecting US architecture.

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Concrete Pyramids - - In this 10 minute audio Quirks and Quarks broadcast, Dr. Michel Barsoum, a professor of Materials Science and Engineering at Drexel University in Philadelphia, thinks the pyramids, or at least part of them, were made of concrete. Not modern concrete, but a simpler kind of cement that nevertheless seems to have survived the eons, and is practically indistinguishable from limestone.

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Cueva de los Cristales - giant crystals in a northern Mexican cave:

• The Crystal Caves - another excellent resource for the caves.

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Cueva de los Cristales - stunning video of these massive crystals (4:56).

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Section 5.2 Quiz - need more practice? Try this online quiz.

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Smelting - refining mineral deposits can have many environmental concerns:

• Smelting Lead - this site provides a very complete review of the lead smelting process.
• Simply Zinc - background on zinc and where it comes from.
• Lead and Zinc Mining - these two metals are often found together when mining.

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Organic Chemistry - the study of compounds that contain carbon:

• An Introduction to Organic Chemistry - this site has a nice introduction to organic chemistry
• Biochemistry4kids - a nice, simplified introduction to the meeting of biology and chemistry.
• Organic Chemistry - knowing the basics of what is an enormously complex and important field in chemistry.

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Carbon Producing Mammal - - A remarkable new animal was discovered in Viet Nam recently by Dr. Alexander McKenzie, a biologist at the Woody Hole Terragraphic Institute. The small mammal seems to be able to consume most kinds of organic matter, and somehow combines it with carbon dioxide from the air, to produce fecal pellets of limestone. Find out more in this 7 minute audio Quirks and Quarks broadcast.

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Organic Compounds - organic compounds form predictable structures:

• Molecular Models - by using the jmol plugin, it is possible to study many organic molecules in 3D.
• Structure and Nomenclature of Hydrocarbons - slight changes in structure define unique organic compounds.

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Hydrocarbons - organic compounds that contain only carbon and hydrogen atoms:

• The Hydrocarbons Page - information, images and 3D models of hydrocarbons.
• Organic Chemistry: An Introduction - hydrocarbons are covered nicely in this introduction to organic chemistry.

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Solar Gas - - Researchers at Sandia National Laboratories in Albuquerque, New Mexico, have developed a way to make gasoline out of solar energy, doing in moments what nature does over eons. In this 10 minute audio Quirks and Quarks broadcast, these researchers say that by focusing solar heat, they can crack carbon dioxide to create hydrocarbons, thus potentially providing a carbon-neutral way to produce hydrocarbon fuels. In effect, they are reversing combustion and turning carbon dioxide back into fuel.

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Introducing Alcohols - an introductory, but in-depth, look at alcohols.

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High Proof Hydrogen - - Hydrogen might be the fuel of the future, except that we don't have a source for it and we don't know how to carry it around. In this 9 minute audio Quirks and Quarks broadcast, Dr. Lanny Schmidt, a professor of Chemical Engineering and Materials Science at the University of Minnesota, and his colleagues have found a way to solve part of the problem. They've constructed a small device known as a reformer that can convert ordinary ethanol - alcohol - into hydrogen to be used in a fuel cell. Since ethanol can be a green fuel, and is easily transported, this could be part of the future hydrogen economy.

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The Organic Chemistry of Plastics - organic solvents that contain only carbon, hydrogen and oxygen atoms:

• How Plastics Work - everything from the history of plastics to how they are made and what they are composed of.
• Macrogalleria - a large website with pretty much everything you could possible want to know about polymers.

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Groups of Organic Compounds - some ideas for organic compounds:

• List of Organic Compounds - Wikipedia will get you started after you have chosen which compound(s) to research.
• Molecular Viewing Gallery - get a 3D view of almost any organic molecule you can think of.

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Research and Development Chemist: Hair Care - the chemistry of this industry is both complicated and lucrative:

• Better Hair Through Chemistry - understanding the chemistry of hair.
• How Hair Colouring Works - hydrogen peroxide, ammonia, sulphur and dyes. All thing chemistry of colouring your hair.

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Organic Compounds - this puzzle reviews naming of compounds. (Also available for download )

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Section 5.3 Quiz - need more practice? Try this online quiz.

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Chapter 6 Resources

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The Six Types of Chemical Reaction - a quick review of each of the six types of reaction.

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Chemical Reactions of Different Types - there are many kinds of reactions, see many examples here!

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Moon Oxygen - - The moon may have no air, but it does have plenty of oxygen. The lunar soil, or regolith, is largely made of oxides like silicon dioxide, calcium oxide and iron oxide. In this 8 minute audio Quirks and Quarks broadcast, Dr. Eric Cardiff, from the NASA Goddard Space Flight Center in Greenbelt, Maryland, is developing a technique to use solar energy to extract the oxygen for use as breathable air and as rocket fuel. (Tip: Download audio files to your hard drive by right-clicking and choosing "Save Link As...")

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Kangaroo Burps - - Kangaroos and cows have a lot more in common than you might think. Namely, they're both grazers and both depend on microbes in their digestive tract to help them breakdown their high-fibre diet. The difference is that cows produce high amounts of the greenhouse gas, methane, in the process. Kangaroos, on the other hand, produce almost none. In this 8 minute audio Quirks and Quarks broadcast, Dr. Athol Klieve, a researcher with the Department of Primary Industries & Fisheries in Queensland, Australia, is studying the gut bacteria of certain species of kangaroo, in the hope that they can be transfered into the digestive system of cattle; and, in doing so, significantly cut back the amount of greenhouse gas they produce.

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Test your knowledge of chemical reactions - these links will use a variety of interactive methods to test your chemical reaction knowledge:

• Chemical Equations quiz - fill in the missing reactants and products.
• Practice Balancing Equations - can you name the reaction type as well?

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Na₃N Synthesized from its Elements - it took many years to discover how to synthesize this elusive compound.

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Stainless Steel - a mixture of iron and carbon, steel is made impervious to rust (iron oxide) by using chromium oxide:

• Stainless Steel - aka "corrosion-resistant steel".
• What is Stainless Steel? - a very complete site about stainless steel.
• Stainless Steel Overview - examine the whole family tree of stainless steel.

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Types of Chemical Reactions - this puzzle reviews chemical reaction types. (Also available for download )

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Section 6.1 Quiz - need more practice? Try this online quiz.

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Rates of Reaction - how quickly the products are formed, and the reactants are used up, can be altered in a number of ways:

• Rates of Reaction - the rate of reaction can be changed, but make sure you know the result of the change.
• Rates of Reaction - a very nice breakdown of the ways reaction rate can be changed.
• Rates of Reaction - another review of reaction rate.

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Diamonds - the unique composition and process that produce on the hardest, most valuable materials on Earth:

• A Diamond's Deep History - a nice interactive explanation of diamonds, from PBS.
• How Diamonds Work - well, maybe "work" isn't the right word, but this site gives a nice overview of diamonds.

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Rate of Chemical Reactions - test your knowledge of factors affecting chemical reaction rates. (Also available for download )

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Temperature and Reaction Rate - glowsticks and water at different temperatures, including an interactive movie.

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Elephant Toothpaste and Reaction Rate - this popular demo can really illustrate how concentration effects reaction rate.

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Catalysts and Reaction Rate - sometimes, the presence of a chemical catalyst speeds up a reaction :

• Catalysts and Inhibitors - use these to control the rate of reaction without dangerous pressures, concentrations or temperature changes.
• Catalytic Converters - in vehicles, this device uses catalysts to clean the exhaust gases.

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Chemical Reactions and Food Preservation - a great example of when slow reaction rates are desired:

• How Food Preservation Works - there are a variety of methods, but almost all involve trying to slow the chemical processes that cause decomposition.
• National Center for Food Preservation - VERY complete source of information for preserving food at home.
• FoodSafetySite - there are many sources of information here for the food service industry.
• Using Argon for Packaging - the less oxygen there is in the food, the less spoilage will occur.

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Reaction Rate in Air bags - have you ever wondered how a safety airbag in your car works?:

• Crash Test Videos - () - want to see airbags in action? Download videos here and see for yourself.
• Gas Laws Save Lives - by carefully engineering tough bags to quickly inflate with the products of chemical reactions, many lives have been saved.
• How Does an Airbag Work? - inflated by a solid rocket booster, but designed to save your life.
• Facts About Sodium Azide - extensive poison information.
• Air Bags - comprehensive information and many good short animations.
• How Air Bags Work: The Future of Air Bags - excellent info on what the future holds for air bags.

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Reaction Rate in Airbags - simulate an inflating airbag deployment:

• Stoichiometry that Saves Lives - combine a lab, a video and an investigation all into one activity.
• Air Bags and Collisions - from Newton's Apple, a video showing car safety. Includes a teacher guide.

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Section 6.2 Quiz - need more practice? Try this online quiz.

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