00:00:30 Chemistry is a way of viewing the beauty and the elegance of the materials that surround

00:00:46 us.

00:00:47 It's that wonder, it's that understanding of the wonder that gives me such great joy

00:00:52 and pleasure to be a chemist.

00:00:56 Atoms and molecules.

00:00:59 Molecules and atoms.

00:01:01 The basic building blocks of the universe.

00:01:04 The world of the chemist.

00:01:07 Chemists understand how different elements combine, delivering answers to questions that

00:01:12 face all of us.

00:01:14 Energy.

00:01:15 Solar.

00:01:16 Nuclear.

00:01:17 Oil.

00:01:18 Coal.

00:01:19 How do we use our finite resources?

00:01:24 Population, feeding the hungry.

00:01:32 Can we grow more on less land?

00:01:35 Can what we grow be more nutritious?

00:01:43 Disease, communicable, contagious, infectious.

00:01:54 Can germs, microbes, viruses, and cancers be arrested or eradicated?

00:02:07 Can we concoct, fuse, and alloy new materials to conserve and extend the use of those we

00:02:13 have?

00:02:16 Earth.

00:02:19 Air.

00:02:22 Fire.

00:02:25 Water.

00:02:28 These were the unlimited resources of the Greek world.

00:02:40 The alchemists tried to create more, but their chemistry was laced with magic and mysticism.

00:02:49 It was chemists like Joseph Priestley who began to formulate a world made up of more

00:02:54 than a hundred different elements.

00:02:57 Priestley and the French chemist Antoine Lavoisier discovered that air itself is a mixture, and

00:03:03 that one of its important ingredients is the same gas that provided the powerful propulsive

00:03:10 punch that carried man to the moon.

00:03:14 While he was getting there, oxygen flowed and made umbilical cord and allowed him to

00:03:20 work and think and observe the earth from a new point of view.

00:03:27 Other chemists discovered other elements and learned how to use them.

00:03:31 Charles Martin Hall, a chemist from Oberlin College in Ohio, showed the world how to extract

00:03:38 shiny metallic aluminum from the red ore in which it had been locked away since the

00:03:43 earth was formed.

00:03:46 Now large land movers wrest the bauxite ore from its ancient home.

00:04:03 Movers carry it to chemical plants where it is further refined to a white oxide.

00:04:09 A mineral, cryolite, is melted.

00:04:12 The oxide is added.

00:04:14 Then just as Hall discovered, an electric current is introduced.

00:04:18 A chemical reaction takes place.

00:04:21 A stream of silvery metallic aluminum is released.

00:04:27 Aluminum, it's light and it's strong.

00:04:50 From the earth of the ancients there came iron ore.

00:04:53 From that ore comes steel, which etches a new silhouette against the modern horizon.

00:05:14 Iron is more than a hard and brittle structural material.

00:05:18 It is a major component of our blood.

00:05:21 Iron is a chemical key to nutrition and health.

00:05:33 Dr. Paul Saltman, a biochemist from the University of California at San Diego.

00:05:40 In my own personal work on iron metabolism, my roots go back 4,000 years now.

00:05:48 2000 BC, Melampus, the great Persian physician, was on the voyage with Jason and the Argonauts

00:05:55 in search of the Golden Fleece.

00:05:58 Prior to their embarking on this great quest of adventure, Melampus prescribed that you

00:06:06 take cast iron filings and you put them into sweet wine and you drink this as an elixir

00:06:11 which was supposed to bring into your body all of those properties of iron.

00:06:16 Strength, you know, sturdiness, vigor, it was supposed to ward off the slings and arrows

00:06:21 of the enemy.

00:06:22 It was supposed to make you masculine and sensual and indeed enhance your sexual prowess.

00:06:28 So that's 4,000 years ago and I'm still working in that same business.

00:06:33 I look at living creatures.

00:06:34 I ask myself, how is the sunlight captured and turned into energy in the form of plants?

00:06:39 I ask myself, how can we understand the nature of our diet so that we can prevent diseases

00:06:47 from occurring by treating properly those very simple problems of trace metal deficiency,

00:06:54 of amino acid deficiency, of knowing how to synthesize vitamins, of, for example, how

00:06:58 can we grow more food?

00:07:05 Our primary interest in this lab has been to apply our knowledge of the chemistry of

00:07:10 iron to discovering better ways to be able to introduce iron into the human body and

00:07:17 in developing those techniques what we've tried to do is to use these test animals,

00:07:23 these little mice, to help us.

00:07:26 We have a radioactive solution of iron which is complex to fructose in this case and we

00:07:32 feed this to our little mouse.

00:07:34 There you can see him eating.

00:07:35 Come on, sweetie.

00:07:36 Take a little whiff on me.

00:07:37 There you go.

00:07:38 That's a good baby.

00:07:39 And we then place him into a chamber which in turn we place into this radioactive counter

00:07:51 which is called a solid state scintillation counter and then we leave him in there for

00:07:59 about five minutes and measure how much iron we have introduced into his body by this little

00:08:10 finite amount of radioactive iron isotope complex, the sugar we have.

00:08:14 After a few minutes of that five minutes of counting, we'll take him out and put him back

00:08:18 in his cage and every day we will count how much radioactive iron remains in the rat's

00:08:24 body.

00:08:25 The more that remains, the more effective is the compound which we've used to bind and

00:08:30 complex that iron molecule and by developing new complexes of iron which we can place into

00:08:37 food without changing their flavor, we can develop fortification techniques that will

00:08:44 make the simplest foods now rich in those essential elements that are vitally needed

00:08:49 for the body's function.

00:08:51 Food and people.

00:08:55 The balance is getting rapidly out of kilter as the population doubles in a generation

00:09:01 and agricultural acreage gives way to sprawling suburbs and crowded cities.

00:09:07 What land is available must be made to produce more food, an ever-present challenge for agricultural

00:09:14 chemists.

00:09:16 They have already helped hold the line against hunger by building elements such as phosphorus

00:09:22 and nitrogen into chemical fertilizers that assure bumper crops on land that may not have

00:09:28 enough of those vital nutrients.

00:09:32 But the competition for this food is great.

00:09:36 Producing food for us has produced more food for insects, weeds, and plant diseases.

00:09:45 Insecticides, herbicides, and fungicides selectively check pests without harming plants

00:09:51 and animals in the same environment, without adding dangerous chemicals to the food chain.

00:10:00 The chemical attack has also nearly obliterated malaria and other insect-borne diseases that

00:10:05 once claimed millions of lives.

00:10:11 But in the main, life is not as short for man and womankind as it once was.

00:10:17 Life-threatening diseases such as pneumonia, diabetes, arthritis, and even some forms of

00:10:23 cancer have yielded to a chemical attack.

00:10:27 Penicillin, cortisone, aspirin, the sulfur drugs, and all of our antibiotics.

00:10:36 Some of these are related to natural materials.

00:10:39 Some have been created synthetically by the pharmaceutical chemist.

00:10:44 But often as a new drug is produced, a new and resistant strain of disease is encountered.

00:10:51 For this reason, new antibiotics are constantly being sought out and grown.

00:10:58 The road to a new antibiotic employs the joint efforts of the pharmaceutical chemist and

00:11:04 tiny microorganisms, or molds.

00:11:08 The mold is isolated and grown on an agar plate.

00:11:15 The product it produces is tested against strains of resistant bacteria.

00:11:20 If it kills the bacteria, more mold is grown.

00:11:26 The antibiotic is separated further, purified, and chemically identified.

00:11:34 After thorough testing, production begins.

00:11:37 Large quantities of mold are grown in the chemical plant, where it is fed everything

00:11:42 it needs to grow and multiply.

00:11:46 The antibiotic is harvested, crystallized, and made available to the physicians of the

00:11:52 world in practical and useful forms.

00:11:55 This is how penicillin, tetracycline, and all the other antibiotics that have been developed

00:12:01 since World War II were born.

00:12:04 For the human race, life has been better, and longer, ever since.

00:12:11 The

00:12:27 changing world, with its ever-growing population and new technological sophistication, has

00:12:34 always placed, and continues to place, new demands on the chemist.

00:12:46 In the petroleum refinery, he learned to manipulate compounds of carbon and hydrogen to make the

00:12:52 fuel that powers our automobiles and airplanes.

00:12:56 The oil that keeps our homes warm and industry alive.

00:13:01 The starting of materials for the hundreds of different plastics and polymers that touch

00:13:06 every aspect of modern life.

00:13:10 Chemicals from petroleum became man-made fibers, nylon, polyvinyl chloride, polystyrene, giant

00:13:19 molecules conceived by chemists to do things that natural products could never do.

00:13:34 World War II.

00:13:35 The Axis powers cut off the Malay Peninsula and its rubber plantations.

00:13:41 Chemists found in petroleum the perfect starting materials for synthetic rubber that would

00:13:46 keep the war wagons rolling.

00:13:58 But someday, perhaps before the end of this century, the oil wells will run dry.

00:14:05 If we continue to burn petroleum as fuel for our cars, homes, and factories, we will have

00:14:11 less of it for the material things we need.

00:14:15 We must look elsewhere for our energy supply.

00:14:19 We must look, as we are already doing, to nuclear energy and the immense power locked

00:14:24 within the core of heavy elements, such as uranium.

00:14:29 We must look to still other energy resources that will carry us beyond the time when our

00:14:35 oil, our natural gas, our coal, and even the uranium that fuels our nuclear plants

00:14:42 run out.

00:14:49 We will certainly look more seriously to the sun, our star, the great nuclear furnace that

00:14:57 has been burning for billions of years.

00:15:03 The sun's energy is locked in trees and plants.

00:15:07 It's released when we burn wood, coal, or oil.

00:15:13 Chemists have helped harness the power of the sun with the solar cell.

00:15:18 Solar cells have been used successfully outside our atmosphere to power satellites and space

00:15:25 vehicles.

00:15:27 The solar cell, direct conversion of the sun's energy to usable power on earth.

00:15:35 Closer to home, chemists and other scientists at the University of Delaware are working

00:15:40 on a sun-powered house.

00:15:42 The panels on the roof collect the sun's heat to warm and cool the house.

00:15:48 However, heat collected on sunny days must be stored for periods when the sun is not

00:15:55 shining.

00:15:56 Dr. Paul Camdeau is solving this problem through the use of certain chemical salts, including

00:16:03 sodium sulfate, which are stored in a heat exchanger in the basement.

00:16:07 We have two kinds of salt hydrates, and this of course is heated by the air arriving from

00:16:14 the collectors.

00:16:16 There is enough capacity in the 120 degree heat storage material to store up approximately

00:16:24 two days worth of heat for the house.

00:16:29 Underneath the heating panels are solar cells for generating electricity.

00:16:34 The starting point for this cell is this sheet of copper, which is pennyweight copper, very

00:16:39 thin, very cheap copper.

00:16:41 Dr. John Meekin of the University of Delaware.

00:16:44 As you can see on the surface, it's a silvery color, which is a thin, electro-deposited

00:16:48 layer of zinc.

00:16:50 We then go into an evaporator and put down about a mil or 25 microns of cadmium sulfide

00:16:56 by a vapor deposition process, and that is the heart of the cell.

00:17:02 Once installed on the roof, the cadmium sulfide solar cell will convert units of the sun's

00:17:08 energy called photons into a flow of electricity.

00:17:13 Eventually, the Delaware Solar Experiment will provide a home with 80 percent of its

00:17:18 electrical needs provided by the sun.

00:17:23 One of the most hopeful dreams of those who would stave off the energy crisis before it

00:17:28 gets much larger is envisioned by scientists and engineers who plan to harness the same

00:17:34 nuclear fusion processes that have kept the sun burning relentlessly for billions of years.

00:17:42 That dream moved a little closer to reality in 1934.

00:17:47 When chemist Harold Urey discovered deuterium, a heavy form of hydrogen which exists in almost

00:17:54 endless abundance in the waters that cover three-quarters of the Earth's surface.

00:18:00 Urey later received the Nobel Prize in Chemistry for this achievement.

00:18:05 With deuterium, man may now be able to do what the sun does, that is, force nuclei of

00:18:12 those deuterium atoms together at extremely high temperatures so that they fuse or stick

00:18:18 together and release tremendous amounts of energy.

00:18:23 There are many different schemes for achieving nuclear fusion on the Earth, but one of the

00:18:28 most appealing involves the use of a laser beam, a narrow but powerful beam of concentrated

00:18:35 light that can cut through steel as if it were butter.

00:18:41 Scientists at the Lawrence Livermore Laboratory of the University of California hope to achieve

00:18:46 fusion power by focusing laser beams on a tiny pellet of deuterium and a heavier form

00:18:53 of hydrogen known as tritium.

00:18:58 The laser pulses heat and compress the deuterium target to conditions more extreme than those

00:19:04 in the center of the sun.

00:19:07 Some of the heavy hydrogen nuclei fuse, releasing energy in the form of heat, which can then

00:19:14 be converted to electricity in a power plant.

00:19:20 The laser and chemists also have an important role in the expanding world of communications,

00:19:27 linking more and more people together by telephone, radio, television, and computers.

00:19:33 In this case, the message is conveyed on a beam of laser light, fed through pliable

00:19:38 glass fibers instead of bulky copper cables that now do the same kind of job.

00:19:44 Dr. Robert Lodese, Bell Telephone Laboratories, Murray Hill, New Jersey.

00:19:51 Well, what we're doing is what we at least think is some of the most exciting chemical

00:19:58 work connected with communications going on today.

00:20:03 Specifically, what we're doing is we're making optical fiber, hair-thin glass fiber like

00:20:08 this, to be used as a communication channel by having light guided down it.

00:20:19 The technique from the chemist's viewpoint that we're practicing is a chemical reaction

00:20:25 between gaseous compounds of silicon and germanium and other things inside of this

00:20:31 tube.

00:20:32 We deposit glass on the inside of this tube and carefully control its composition and

00:20:38 vary it in a predetermined way, and then we collapse that tube and then we draw fiber

00:20:44 from that collapsed tube.

00:20:56 We're making fiber in this stage of the process.

00:21:04 We're using the solid rod with the composition that we carefully put into it in the previous

00:21:10 step.

00:21:11 And what Frank has done is put that rod into a high temperature furnace and heat it up

00:21:15 to the softening point of glass, then pull the fiber out of it, attach the end of the

00:21:21 fiber to that rotating drum.

00:21:23 Now by controlling the speed of rotation of the drum and the temperature of the furnace,

00:21:28 we can control very accurately the diameter of the fiber which we make.

00:21:33 Once the molten glass rod is formed into a single fiber, it can be converted into a communications

00:21:40 cable, each fiber cable carrying thousands of times more telephone messages or television

00:21:46 pictures than a copper cable of the same size can.

00:21:51 Even more intriguing is that copper is a metal which will eventually run out, while

00:21:56 the glass fibers are made of silica.

00:21:58 Silica, of course, is made of sand, an almost inexhaustible resource.

00:22:04 However, developing optically pure glass fiber posed many special problems for Bell Laboratories

00:22:11 chemists.

00:22:12 It turns out that you must reduce the impurity level of critical impurities like iron to

00:22:17 a few parts per billion, and the chemist has made that kind of contribution.

00:22:23 This glass that we've made is perhaps the purest material that man has ever made.

00:22:29 One way of looking at that is, what is the transparency of the glass?

00:22:34 If the ocean water had the same transparency as our glass, you'd be able to stand on the

00:22:41 deck of a ship with appropriate illumination on a sunlit day and see to the bottom of the

00:22:45 sea.

00:22:46 For the laser that makes that light beam that is carried by the optical fiber, special

00:22:51 types of crystal must be grown.

00:22:54 One such crystal is slowly drawn from a molten mass, heated to a temperature of nearly 2,000

00:23:01 degrees Celsius.

00:23:04 To understand how crystals grow, Bell chemists use a computer to simulate the varying conditions,

00:23:11 including temperature and growth rate, that will build up a superstructure of atoms that

00:23:16 will form the best crystal for use in the laser.

00:23:20 This is a single crystal that was prepared by this technique, and it has a structure

00:23:25 over the whole dimension, like this, with every aluminum atom in just the right place,

00:23:33 every yttrium atom in just the right place, and just a smidgen of neodymium, which is

00:23:38 what gives it this purple color, and what's actually the material that lays it.

00:23:47 Earth itself is the chemist's laboratory.

00:23:50 There is little opportunity to compare, contrast, weigh, or measure against anything other than

00:23:57 the things found on this Earth.

00:24:02 The first steps to expand our knowledge beyond this planet were taken when men landed on

00:24:07 the moon.

00:24:09 Scooped up on the moon, its rocks and dust tell the chemist where our satellite came

00:24:14 from, and how is it like our own planet, and how is it different?

00:24:20 The moon rocks brought back through space are a chemical puzzle to be taken apart on

00:24:25 Earth.

00:24:26 A puzzle that, when pieced together again, will tell us more about our solar system,

00:24:32 and how we and it fit in with the rest of the universe.

00:24:38 Seen under the microscope in polarized light, the rocks give clues to what elements they

00:24:45 contain.

00:24:46 A glitter here means iron, a fleeting color there means lead.

00:24:52 And under the scanning electron microscope, each grain of moon dust looks like a world

00:24:58 in itself, battered by millions of micrometeorites.

00:25:04 Undoubtedly the moon is dead, cold, and lifeless.

00:25:11 But what about Mars, and the other worlds strewn across light years of space?

00:25:18 Chemists are now probing for life on these and other planets, trying to understand matter,

00:25:24 energy, and life, to explain natural events that occur here on Earth.

00:25:31 Chemists have found ways to fortify foods with needed nutrients, increase crop yields

00:25:37 with fertilizers and pesticides, fight disease with medical agents, and develop metals and

00:25:43 fibers that do jobs impossible with natural materials.

00:25:48 They have found new sources of energy, new methods of storing heat, and new communications

00:25:57 techniques.

00:25:58 Deep in space, spectroscopes have now found the chemicals necessary to life.

00:26:06 Probes, telescopes, and voyaging vehicles are providing answers to some of our scientific

00:26:13 questions, and also providing some new questions.

00:26:19 Does the universe end out there?

00:26:24 Is there no limit?

00:26:27 We do not know.

00:26:29 What we do know is, there is no limit to the curiosity of chemists.