“The Chemistry of Chocolate” uses chocolate-making to illustrate and explain chemical reactions related to heat, melting point, and formation of crystal structures. Also in this collection: news stories from the NBC News Archives on the history of chocolate, and its health benefits; Scientific American articles, graphs and maps on worldwide production of cocoa beans and consumption of cocoa, largely in the form of chocolate.
“It's a Wash: The Chemistry of Soap” explains how soap and detergents — surfactants — affect the surface tension of H2O to break up greasy dirt. We also profile 21st Century Chemist Facundo Fernandez at Georgia Tech, who uses chemistry to detect dangerous or ineffective fake pharmaceutical drugs and medicines. Also in this collection: news stories from the archives of NBC News and Scientific American on counterfeit drugs, and on hand-washing and the spread of germs and disease; plus, a history of soap timeline and Victorian-era soap recipes.
“Water: H2O Molecules Made Clear” explains how the structure and behavior of H2O in liquid form gives water its properties, and make it a chemical essential for life. (The Greek word for “life” is traced in a separate Word Root.) Also in this collection: a Victorian-era depiction of the water molecule; news stories on water and molecules from the NBC News Archives, and illustrations and tables on The Water Cycle, water quality and water use.
“The Chemistry of Cheese” (part of a 6-part Cheeseburger Chemistry series) uses cheese-making to explain protein denaturing, coagulation, and the difference between chemical and physical change. Also in this collection: news stories on Swiss cheese and Blue (or Bleu) cheese from the NBC News Archives, and graphs and charts on cheese production in the U.S.
“Mirror Molecule: Carvone” uses carvone, a chiral molecule, to explain how the “handedness” of a molecule can change its properties — in this case giving us the differing flavors of spearmint, caraway and dill. Also in this collection: an 1853 drawing by Louis Pasteur of a chiral crystal; The Periodic Table of Elements — as it was imagined in previous centuries and as it stands today; and an NBC News profile of Oliver Sacks, author of “Uncle Tungsten: Memories of a Chemical Boyhood.”
“The Chemical Bond Between Cloves and Nutmeg” focuses on the variety, strengths — and placement — of chemical bonds in the structures of two nearly identical molecules, eugenol and isoeugenol. In a “bonding” story of another kind, we profile Purdue materials chemist Jon Wilker, who's making synthetic adhesives based on the glues mussels produce underwater. (For another story on use of polymers in materials, see “The Science of Skis.”) Also in this collection: early 19th century illustrations of atom “combinations,” and an 1888 recipe for household glue.
“The Chemistry of Burgers” (part of a 6-part Cheeseburger Chemistry series) outlines myoglobin protein structures and their chemical changes when exposed to heat — part of what turns a patty of red, raw ground beef into a tasty brown burger. Also in this collection: burger-related news stories from the archives of NBC News and Scientific American — plus a Burger-related NBC Learn video.
“The Chemistry of Bread” (part of a 6-part Cheeseburger Chemistry series) uses bread-making to illustrate and explain how yeasts work to convert starches and sugars in flour to CO2 gas (fermentation); effects of heat on gas; and gluten protein structures. Also in this collection: news stories on bread-making and grain crops from the archives of NBC News and Scientific American, plus graphs, maps and charts on global wheat production and consumption.
“The Chemistry of Tomatoes” (one in a 6-part Cheeseburger Chemistry series) outlines the role ethylene plays in ripening tomatoes (and other fruits); the role of lycopene in color change; anddiffusion of gas. Also in this collection: news stories on tomato mutation, genetic modification and ripening from the archives of NBC News and Scientific American, plus tables and maps on global tomato production, processing and consumption. And the first in our Chance Discoveries series: the story behind Post-it Notes.
“The Chemistry of Green” outlines the role of chlorophyll in photosynthesis, and the role ofpigments in making plants green (or making them appear green). Also in this collection: news stories from the archives of NBC News and Scientific American on chlorophyll, sunlight andbiofuels, green things (trees, grass, algae) and, for fun, a 1990 story about crayon colors; plus a diagram of the electromagnetic spectrum, and maps of plant zones.
“The Chemistry of Pickles” (one in a 6-part Cheeseburger Chemistry series) describes the role offermentation, lactic acid, and pH in the process of pickling food to preserve it. (The Latin root of the word “preserve” is traced in a separate Word Root.) Also in this collection: news stories from the archives of NBC News and Scientific American on “bad” bacterial growth on food; the acidification and desalination of ocean water; plus a profile of a proud pickle-maker. Finally: a Pickle History Timeline, and a 1900 recipe for Green Sour Pickles.
“The Chemistry of Condiments” (one in a 6-part Cheeseburger Chemistry series) uses ketchup, mustard and mayo to explain two different types of mixtures: suspensions and colloidal dispersions (emulsions). Two related Chemistry Now videos explain H2O and emulsions in more depth. Also in this collection: news stories from the archives of NBC News and Scientific American on mixtures; a 1910 recipe for “Mayonnaise Dressing” and, for fun, a history of salad dressings. Plus, a Chance Discovery story on how saccharin, cyclamate and aspartame were discovered
It's a staple of Spring Cleaning: all-purpose ammonia cleaner. “The Dirt on Ammonia as a Cleaning Agent” explains how ammonia works with water to dissolve fatty acids, like stearic acid, in greasy dirt. Also in this collection: news stories from the archives of NBC News and Scientific American on ammonia in nitrogen fertilizer, in Earth's atmosphere and beyond it; and hazardous chemicals (especially when mixed) in household cleaners.
An 18-year-old London chemistry student tries to make synthetic quinine for malaria treatment, and instead creates the first synthetic dye. We tell the story of this 1856 Chance Discovery that transformed the textile industry worldwide. We also profile a 21st century chemist, Purdue's Mary Wirth, whose nanomaterials research makes cancer “markers” easier to detect in blood tests. Also in this collection: news stories from the archives of NBC News and Scientific American on food and fabric dyes, and cancer screening; and charts showing just how small “nanoscale” is.
Roses are red; violets are...well, violet — but why? “The Chemistry of Flower Color” explains howpigment molecules — carotenoids and anthocyanins — give flowers the colors we see. Also in this collection: news stories from the archives of NBC News and Scientific American on desert wild flowers, pollination, the cut-flower industry, and why flowers have scents; color plates of several floral families; and a flowery offering from Robert Louis Stevenson.
The 1930s invention of nylon revolutionized the global textile and materials industry. “Fabricating Fabric” outlines the molecular structure and impact of the first all-synthetic fiber. And we profile 21st century chemist Malika Jeffries-EL from Iowa State, who devises energy-efficient organic semiconductors and LEDs. Also in this collection: copies of the original nylon patents; and related news stories and articles from the archives of NBC News, Scientific American, and the Chemical Heritage Foundation.
It's both horrifying and fascinating, the way venomous sea snails paralyze, then kill, their prey. We profile 21st Century Chemist Mande Holford of the City University of New York, who is working tosynthesize these biotoxins and develop powerful new painkillers. Also in this collection: news stories from the archives of NBC News and Scientific American on snail, spider and cobra venom, and on pain sensation and control — and a “universal” pain-rating scale.
Smell that? Our sense of smell is a complex set of chemical reactions. We profile 21st Century Chemist Nate Lewis, who's working to develop an artificial “nose” that can help detect odors, including hazardous gases and chemicals. A story on the carvone molecule adds information on how the nose distinguishes odors. Also in this collection: news stories from the archives of NBC News and Scientific American on air testing, sense of smell (human and canine) — and a Periodic Table of “Smellements.”
On the anniversary of the final capping of the gushing oil well in the Gulf of Mexico in 2010, we explain the chemistry of dispersants and immiscibles, in “How to Wash an Ocean.” We also mark the International Year of Chemistry with a video outlining chemistry's “10 Big Questions,” as selected by our content partner, Scientific American. Also in this issue: news stories from the archives of NBC News and Scientific American on the Gulf oil spill and cleanup; a slide show on the oil spill's impact on birds and wetlands, and a chart comparing several notable oil spills.
21st Century Chemist Kent Kirshenbaum of New York University engineers and folds synthetic peptoids in hopes of creating “hunter-killer” molecules that can target and destroy deadlybacteria like staph (MRSA). A separate Chance Discoveries video tells the story of the first shatter-resistant safety glass. Also in this collection: news stories from the archives of NBC News and Scientific American on drug-resistant “superbugs” and on glass (windshields and cathedral windows).
We mark the award of the 2011 Nobel Prize in Chemistry with a look at two other notable Nobel-worthy advances: discovery of buckminsterfullerene, a 'surprise' carbon allotrope (along with diamond and graphite); and one of the most promising recent Chance Discoveries: graphene. Also in this collection: news stories from the archives of NBC News and Scientific American on graphene, buckyballs, and past Nobelists in Chemistry.
Why do tree leaves turn gold, orange and scarlet in the fall? “Chemistry of Changing Leaves” explains the role of pigment molecules, including chlorophyll, carotenoids, and anthocyanin. We also profile North Carolina State “green” chemist Elon Ison, who is designing catalysts to make safer, cleaner alternative fuels. Also in this collection: news stories from the archives of NBC News and Scientific American on leaf change and “green” fuels, plus a NOAA diagram on why seasons change, and charts and photographs for virtual leaf-peepers.
So much of what we wear, sit on, use and touch every day is made, at least in part, of polymer plastics. “Chance Discoveries: Polyethylene” tells the story of how the world's most used plastic was first formed and developed into the “miracle” material of post-WWII America (as explained in a 1945 filmstrip, “The Kingdom of Plastics.”) Also in this collection: news stories from the archives of NBC News and Scientific American on plastics-related health and environmental concerns.
Are you arachnophobic? Acrophobic? Ophidiophobic (afraid of snakes)? “Chemistry of Fear and Fright” explains how two hormones, adrenaline and cortisol, work to trigger a cascade of “fight or flight” fear responses when you're confronted by a spider, great height or snake. Also in this collection: news stories from the archives of NBC News and Scientific American on common fears and phobias; a Word Root on the origin of “phobia”; and a photo slide show of common fear response triggers.
As light as nylon yet harder than steel — “Chance Discoveries: Kevlar” tells the story of lab experiments with aromatic polyamides that produced the synthetic material now common in bicycle helmets, tires, and “bulletproof” police and combat gear (although not in fashion, despite the early designs of one apparel company). Also in this collection: stories from the archives of NBC News, Scientific American, and The Washington Post on early and current uses of Kevlar, and advances in anti-ballistic materials.
Most recipes for Thanksgiving pumpkin pies call for clove and nutmeg — two distinct spices that come from two nearly identical molecules: eugenol and isoeugenol. “The Chemical Bond Between Cloves and Nutmeg” explains how the strength and placement of just one chemical bond makes eugenol responsible for the taste and aroma of cloves, and isoeugenol responsible for the taste and aroma of nutmeg. Also in this Thanksgiving collection: some pumpkin history and background from the NBC Learn collections; facts and figures on pumpkins and spices; and a 1910 Army pumpkin pie recipe that calls for products with the molecular properties of both eugenol and isoeugenol.
“The Chemistry of CO2: Carbon Dioxide,” uses CO2's molecular structure to explain and illustrate the Octet Rule (Rule of 8); and examines CO2's role in carbonation, the carbon cycle, and the Earth's atmosphere, surface temperature, and ocean acidity. Also in this collection: stories from the NBC Learn-NSF “Changing Planet” series; stories on CO2 emissions, capture and storage from the archives of NBC News and Scientific American; and charts and graphs on CO2 output trends.
A Swiss chemist tries to stain-proof tablecloths by coating them with a viscous cellulose-based liquid, but it peels off in clear sheets when it dries. That new material, when refined, revolutionizes the way food is packaged and sold. Also in this collection: news stories from the archives of NBC News and Scientific American on food packaging, and vintage cellophane ads. We also profile Georgia Tech molecule designer Stefan France, who hopes his work will stop or slow effects in the brain of diseases such as Alzheimer's.
Northern areas in winter are showcases for crystals. “The Chemistry of Ice” explains what happens when liquid H2O freezes into a solid crystal. “The Chemistry of Salt” examines the molecular structure of sodium chloride, or NaCl, and explains how this salt crystal can melt ice crystals on sidewalks and roads. Also in this collection: stories from the archives of NBC News and Scientific American — plus maps, a graph and a slideshow — on crystals, salt, snow, ice, and ice cream.
How do atoms bond to form molecules? We use common table salt to show what happens between the electrons and nuclei in atoms of sodium and atoms of chlorine to bond them together into crystals of sodium chloride (NaCl). Also in this collection: related Chemistry Now videos; news stories from the archives of NBC News and Scientific American on electrons and orbitals; and, from the collections of the Chemical Heritage Foundation, an 1808 diagram of “Atoms and Their Combinations.”
This original six-part Chemistry Now video series uses components of a cheeseburger to illustrate and explain common chemistry concepts and reactions. The Bun? Gas and sugar reactions. Cooking burgers? Heat, protein and Maillard reactions. Cheese? Phase change, from liquid to solid, and coagulation. Tomatoes? The role of ethylene in ripening and lycopene in color change, and gas diffusion. Pickles? Fermentation, acid and pH. And condiments? Mixtures: suspensions (ketchup and mustard) and emulsions (mayo and mayo-based special sauces).
In this Chemistry Now original video series, we find examples of chemistry in the holidays and seasons of the annual calendar: Valentine's Day (“The Chemistry of Chocolate”), St. Patrick's Day (“The Chemistry of Green: Chlorophyll”), Halloween (“The Chemistry of Fear and Fright”) and Thanksgiving (“The Chemistry of Pumpkin Pie Spices”); from spring cleaning (“Chemistry of Household Cleaners”) to summer (“The Chemistry of Flower Color”), autumn (“The Chemistry of Changing Leaves”) to northern winters (“The Chemistry of Ice”).
In this original Chemistry Now video and animation series, a dozen molecules and compounds are “profiled” to explain what makes H2O watery and soap soapy; why salt dissolves in water and how soap dissolves grease; why spearmint, dill, cloves and nutmeg have different tastes and aromas; and why grass is green, roses are red and violets are, well, violet. Also covered: molecular bonds (single, double, covalent, hydrogen, ionic); the Octet Rule, deprotonation, acids and bases, surfactants and surface tension, crystal lattice structures, polymers, polyamides and allotropes.
Many (if not most) experiments in the chemistry lab do not get significant results — or the expected results. In this Chemistry Now original video series, we highlight the curiosity, daring, and creativity of the best bench chemists by telling the stories of the people and experiments behind eight notable discoveries made by chance in the chemistry lab: synthetic dye, cellophane, polyethylene, safety glass, artificial sweeteners (saccharine, cyclamate and aspartame), Kevlar, and graphene.
This Chemistry Now original video series takes viewers into the research labs of nine 21st Century Chemists funded by the National Science Foundation, showcasing their work on today's “headline” challenges — cleaner alternative fuels; effective treatments for malaria, cancer and Alzheimer's — and their promising advances on a range of intriguing ideas: underwater adhesives based on mussel glue, new painkillers based on snail venom, artificial noses and organic semiconductors. We also outline the chemistry's “10 Big Questions” as selected by our content partner, Scientific American.