... about Chemistry.

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0:00:02 > 0:00:05For many of us, there are few subjects more confounding than chemistry.

0:00:05 > 0:00:08But, in truth, it's actually a lot like cooking.

0:00:08 > 0:00:10You take some ingredients,

0:00:10 > 0:00:13you mix them together in a bowl, or maybe a beaker,

0:00:13 > 0:00:17and you end up with all sorts of surprising concoctions.

0:00:17 > 0:00:19Although, in chemistry, it's probably a good idea

0:00:19 > 0:00:22if you don't lick the spoon afterwards.

0:00:22 > 0:00:27I'm here to distil the truth, with mind-bending questions, such as -

0:00:27 > 0:00:30why do things go bang?

0:00:30 > 0:00:33Can I turn lead into gold?

0:00:33 > 0:00:36And why would anyone want my pee?

0:00:36 > 0:00:42Just a few of the things you need to know about your chemical life.

0:00:44 > 0:00:46Let's start with something nice and simple.

0:00:46 > 0:00:48Hopefully.

0:00:52 > 0:00:55The world is like one big laboratory,

0:00:55 > 0:00:57full of chemical reactions.

0:00:57 > 0:01:01But you don't need a PHD to prove it.

0:01:01 > 0:01:03You just need some household ingredients.

0:01:03 > 0:01:06TV ADVERTISEMENT: It's pure and good. And it's so thrifty!

0:01:06 > 0:01:10Baking soda is used in muffins to help them rise.

0:01:12 > 0:01:16But God forbid that you mistake your vanilla extract for vinegar,

0:01:16 > 0:01:19because it'll blow your muffin top off.

0:01:21 > 0:01:22Oh!

0:01:22 > 0:01:23Why is that?

0:01:24 > 0:01:29Well, the chemical recipe for this muffin gone wrong looks like this.

0:01:30 > 0:01:32Which looks massively complicated,

0:01:32 > 0:01:36but really, it means that baking soda is a base substance,

0:01:36 > 0:01:41made up of sodium, carbon, oxygen and hydrogen atoms,

0:01:41 > 0:01:43forming a molecular structure

0:01:43 > 0:01:44that looks like this.

0:01:46 > 0:01:50Vinegar, meanwhile, is a carboxylic acid made up of these atoms

0:01:50 > 0:01:52and its molecular structure

0:01:52 > 0:01:53looks like this.

0:01:55 > 0:01:58The thing you need to know about acids and bases

0:01:58 > 0:02:00is that they're opposites.

0:02:00 > 0:02:02And when they're forced to mix,

0:02:02 > 0:02:07the atoms rearrange themselves to form new substances.

0:02:07 > 0:02:11And it's this act of two substances coming together to form another one

0:02:11 > 0:02:14that's at the heart of all chemical reactions.

0:02:14 > 0:02:18The simplest chemical reaction that everybody has seen all the time

0:02:18 > 0:02:22without even knowing, probably, that it's a chemical reaction, is burning.

0:02:22 > 0:02:25You are combining things together, air and paper,

0:02:25 > 0:02:27and you're producing new chemicals.

0:02:27 > 0:02:30You're producing carbon dioxide and water.

0:02:30 > 0:02:34Part of the fun of chemistry is the ability of chemicals

0:02:34 > 0:02:38to transform products which are often quite unlike their parents.

0:02:38 > 0:02:40In the case of our vinegary muffin,

0:02:40 > 0:02:43it's the production of carbon dioxide

0:02:43 > 0:02:45which accounts for all the frothy mess.

0:02:45 > 0:02:49The lesson you should take from this is - always read the label.

0:02:50 > 0:02:53You will no doubt have noticed a lot of letters

0:02:53 > 0:02:57and numbers making up those chemical equations.

0:02:57 > 0:02:58And those letters, like...

0:03:01 > 0:03:03..they represent the elements -

0:03:03 > 0:03:06the basic building blocks of chemistry.

0:03:06 > 0:03:08And they are very interesting things, elements,

0:03:08 > 0:03:11because, just like us, each has its own persona.

0:03:11 > 0:03:13And, just like us,

0:03:13 > 0:03:16they don't necessarily get along with each other.

0:03:16 > 0:03:17Which makes me wonder...

0:03:22 > 0:03:24Oxygen, lead,

0:03:24 > 0:03:27neon, mercury.

0:03:27 > 0:03:30In total, there are 118 elements.

0:03:30 > 0:03:31And, like us,

0:03:31 > 0:03:34they all behave differently.

0:03:34 > 0:03:36To keep them in check, we've created

0:03:36 > 0:03:38a kind of chemical prison -

0:03:38 > 0:03:40the periodic table.

0:03:40 > 0:03:43And it works like this.

0:03:43 > 0:03:46Vertically, elements are organised into three main groups -

0:03:46 > 0:03:51metals, nonmetals and metalloids.

0:03:51 > 0:03:54Horizontally, the elements are arranged into rows

0:03:54 > 0:03:56according to their atomic number.

0:03:58 > 0:04:00The lightweight hydrogen has been put right at the top,

0:04:00 > 0:04:03because its mass is just one,

0:04:03 > 0:04:06which means it only has one proton.

0:04:06 > 0:04:08The atomic number of an atom is defined

0:04:08 > 0:04:11as the number of protons, as well as the number of electrons

0:04:11 > 0:04:15that are spinning around, or orbiting around that nucleus.

0:04:15 > 0:04:18And it's the number of electrons on the outside of each element

0:04:18 > 0:04:20which governs its chemical reactivity.

0:04:20 > 0:04:23There are 98 naturally-occurring elements in the periodic table,

0:04:23 > 0:04:25plus there are some additional ones,

0:04:25 > 0:04:27which we have to synthesize artificially.

0:04:27 > 0:04:32And the lower you go, the heavier an element becomes.

0:04:32 > 0:04:34Down in the basement,

0:04:34 > 0:04:38the radioactive ununoctium has a mass of 118 -

0:04:38 > 0:04:40a superheavyweight.

0:04:41 > 0:04:44And which cell an element has been assigned to

0:04:44 > 0:04:46can tell us how it will react to another.

0:04:47 > 0:04:51Carbon, for example, has little trouble mixing with others.

0:04:51 > 0:04:52Amigos!

0:04:52 > 0:04:56Whereas Francium is notoriously violent, especially when wet.

0:04:58 > 0:05:01But it's the combinations that you really need to keep an eye on.

0:05:01 > 0:05:05When sodium meets chlorine, you get sodium chloride -

0:05:05 > 0:05:07common table salt.

0:05:07 > 0:05:10But add three oxygen atoms, and give it a jolt,

0:05:10 > 0:05:12and you get sodium chlorate -

0:05:12 > 0:05:14weed killer.

0:05:14 > 0:05:17And if that comes into contact

0:05:17 > 0:05:19with sugar, you get an explosion.

0:05:19 > 0:05:21And we could go on forever,

0:05:21 > 0:05:24because the potential combinations are endless.

0:05:24 > 0:05:27As you would expect, most of the ones we know about

0:05:27 > 0:05:31were found by accident, or through trial and error.

0:05:32 > 0:05:35But we should probably end things at this point.

0:05:35 > 0:05:37We might give the inmates ideas.

0:05:39 > 0:05:42While some chemical combinations seem terribly dramatic,

0:05:42 > 0:05:47there are plenty of others that seem really quite uneventful.

0:05:47 > 0:05:50But even so, we couldn't live without them.

0:05:50 > 0:05:55In fact, you'd be surprised at the level of our chemical dependency.

0:05:59 > 0:06:01The truth is - if it weren't for chemistry,

0:06:01 > 0:06:03we wouldn't even make it out of bed.

0:06:05 > 0:06:11For starters, we take roughly 14,000 breaths of air every day.

0:06:11 > 0:06:14And it alone is made up of hundreds of chemicals,

0:06:14 > 0:06:20including nitrogen, oxygen, argon, carbon dioxide and water.

0:06:22 > 0:06:26Our bodies are made up of 60% H20,

0:06:26 > 0:06:28and without regular refills, we'd be done for.

0:06:29 > 0:06:32Next comes breakfast.

0:06:32 > 0:06:34Without the iron in our cereal,

0:06:34 > 0:06:36we'd become anaemic

0:06:36 > 0:06:38and riddled with worms.

0:06:38 > 0:06:40Not enough iodized salt

0:06:40 > 0:06:44and our thyroid glands would swell into goitres.

0:06:44 > 0:06:46And without glucose,

0:06:46 > 0:06:47we'd stumble around

0:06:47 > 0:06:49like braindead zombies.

0:06:49 > 0:06:52All in all, not a pretty sight.

0:06:52 > 0:06:57But our chemical dependency has gone well beyond food and drink.

0:06:57 > 0:07:02We use hundreds of substances in things like soaps and toothpaste,

0:07:02 > 0:07:05without which we'd be smelly, hairy and toothless.

0:07:05 > 0:07:09You may have noticed that we're still naked at this point.

0:07:09 > 0:07:11So, to keeps things decent, we cover ourselves

0:07:11 > 0:07:15with chains of repeating molecules, called polymers,

0:07:15 > 0:07:18like wool, nylon and polyester.

0:07:18 > 0:07:20A polymer is a long-chain molecule

0:07:20 > 0:07:22that's made up usually of a repeating series

0:07:22 > 0:07:24of so-called molymers.

0:07:24 > 0:07:27Like imagining putting a bead or a series of beads on a chain.

0:07:27 > 0:07:28You had two different colours.

0:07:28 > 0:07:31Then, you could alternate them red-green, red-green, like that.

0:07:31 > 0:07:34Polymers also occur in natural compounds.

0:07:34 > 0:07:35In plants and animals,

0:07:35 > 0:07:37but also, we're familiar with them

0:07:37 > 0:07:40as synthetic substances that chemists make.

0:07:40 > 0:07:41So, while some of us try to

0:07:41 > 0:07:43make up for our deficiencies

0:07:43 > 0:07:46with wigs made from breathable nylon,

0:07:46 > 0:07:50others set about enhancing their features with cosmetics.

0:07:50 > 0:07:53Once upon a time, cosmetics were truly poisonous

0:07:53 > 0:07:56and contained things like white lead,

0:07:56 > 0:07:58which turned your skin black

0:07:58 > 0:08:00and made your eyes bulge,

0:08:00 > 0:08:02and induced a slow death.

0:08:02 > 0:08:05Even today's versions contain

0:08:05 > 0:08:07trace elements of heavy metals.

0:08:07 > 0:08:10Which is why I only very rarely wear makeup.

0:08:10 > 0:08:13900 chemicals before nine in the morning,

0:08:13 > 0:08:16and your chemical day has only just begun.

0:08:20 > 0:08:22Before you leave, though,

0:08:22 > 0:08:24it's advisable to pay a quick visit to the bathroom.

0:08:24 > 0:08:27And strangely, I'm going to be coming with you,

0:08:27 > 0:08:32because I'd like to spend a little bit of time examining your urine.

0:08:32 > 0:08:34Now, oddly enough, I'm not alone in this one.

0:08:34 > 0:08:37Plenty of people would like to join me.

0:08:37 > 0:08:38Let me explain.

0:08:42 > 0:08:44You probably think of pee as waste.

0:08:44 > 0:08:48But it has some very valuable components.

0:08:49 > 0:08:52The most sought after is urea.

0:08:52 > 0:08:58A nitrogen-rich compound that is colourless and odourless.

0:08:58 > 0:09:01But when the urea breaks down, it forms ammonia

0:09:01 > 0:09:05which, while smelly, is nature's bleach.

0:09:05 > 0:09:08This explains why the Romans collected urine -

0:09:08 > 0:09:11to whiten their togas

0:09:11 > 0:09:13and even their teeth.

0:09:13 > 0:09:18Human and animal urine is still harvested all over the world.

0:09:18 > 0:09:24One town in Mexico collects 4,500 litres during carnival week alone,

0:09:24 > 0:09:26selling it for a tidy profit.

0:09:26 > 0:09:28Ole!

0:09:28 > 0:09:32Health professionals collect your pee for entirely different reasons.

0:09:32 > 0:09:34Urine analysis is a great way

0:09:34 > 0:09:37of measuring the body's overall chemical balance.

0:09:37 > 0:09:40It can tell you if you're pregnant, for example,

0:09:40 > 0:09:42or if you have an infection.

0:09:42 > 0:09:44Health professionals love urine.

0:09:44 > 0:09:46You know the expression "You are what you eat"?

0:09:46 > 0:09:47Well, that's mostly true.

0:09:47 > 0:09:50Do you know how they used to find out whether somebody had diabetes?

0:09:50 > 0:09:53Easy - you take a urine sample, you dip your finger in it,

0:09:53 > 0:09:54and you taste it.

0:09:54 > 0:09:57And if it's sweet, your patient has got diabetes,

0:09:57 > 0:10:00cos they're not metabolising sugars properly.

0:10:00 > 0:10:04It's also a good way to detect alcohol and drugs in the system.

0:10:04 > 0:10:07Although the police generally don't do this by the roadside.

0:10:07 > 0:10:10It's a bit messy.

0:10:10 > 0:10:13Pee, however, has a more dangerous side.

0:10:15 > 0:10:1917th-century alchemist Hennig Brand distilled his own,

0:10:19 > 0:10:24hoping to extract gold, but discovered phosphorus instead,

0:10:24 > 0:10:26which is what makes matches burn so bright.

0:10:29 > 0:10:33Today, urine and urea are used in everything, from fertilizers

0:10:33 > 0:10:36to fire extinguishers.

0:10:36 > 0:10:38In fact, it's so useful,

0:10:38 > 0:10:41we've had to chemically synthesise it to keep up with demand.

0:10:41 > 0:10:45You'll find it in beauty products, dish soap,

0:10:45 > 0:10:50even on pretzels to give them brown glaze.

0:10:50 > 0:10:51And urine is still used

0:10:51 > 0:10:54in the traditional manufacture of tweed clothing,

0:10:54 > 0:10:56which might explain why people will avoid you

0:10:56 > 0:11:00if you wear your tweed jacket in the rain.

0:11:00 > 0:11:02So, next time you go for a wee, remember -

0:11:02 > 0:11:05you could be flushing away a fortune.

0:11:09 > 0:11:13That gives a whole new meaning to taking the...you know what I mean.

0:11:13 > 0:11:15But hang on a minute,

0:11:15 > 0:11:18what was that about pee being potentially explosive?

0:11:18 > 0:11:21Well, it's all to do with combustion, apparently.

0:11:21 > 0:11:24That's the scientific term for blowing things up.

0:11:24 > 0:11:26And combustion can take many forms -

0:11:26 > 0:11:30some good, some bad, some downright ugly.

0:11:30 > 0:11:33So I suppose my next question should be...

0:11:39 > 0:11:44Ever since man-made fire, we've been experimenting with combustion

0:11:44 > 0:11:47with varying degrees of success.

0:11:47 > 0:11:49Bangs are usually the result of

0:11:49 > 0:11:51a fuel reacting with oxygen,

0:11:51 > 0:11:55and a heat source, like a spark.

0:11:55 > 0:12:02This creates heat, light, pressure and sound.

0:12:02 > 0:12:04Of course, none of these results

0:12:04 > 0:12:06are strictly chemical.

0:12:06 > 0:12:10This is where chemistry partners up with its old friend - physics.

0:12:10 > 0:12:15Because really, a bang is a release of energy in a short burst.

0:12:15 > 0:12:18In an explosion, you have a molecule.

0:12:18 > 0:12:19If you give it enough energy,

0:12:19 > 0:12:22it would prefer to exist in some other form.

0:12:22 > 0:12:26That other form involves breaking high-energy bonds.

0:12:26 > 0:12:28Those bonds essentially fragment apart

0:12:28 > 0:12:31in a very violent and rapid fashion,

0:12:31 > 0:12:34releasing large amounts of energy and large amounts of gas.

0:12:34 > 0:12:37The type of bang depends on the chemicals you use,

0:12:37 > 0:12:39and how you set them off.

0:12:41 > 0:12:45Fireworks contain elements that give them their distinctive colours.

0:12:45 > 0:12:47Sodium makes yellow,

0:12:47 > 0:12:48copper - green,

0:12:48 > 0:12:50and potassium - violet.

0:12:50 > 0:12:52But the explosive ingredient

0:12:52 > 0:12:54is actually gunpowder.

0:12:54 > 0:12:56If you want to big up the bang,

0:12:56 > 0:12:59you'll need something more powerful.

0:12:59 > 0:13:03Like nitroglycerine, which is highly volatile.

0:13:03 > 0:13:05Ideal for making dynamite,

0:13:05 > 0:13:06though be careful

0:13:06 > 0:13:08how you handle her.

0:13:10 > 0:13:12You CAN actually harness the power of bangs

0:13:12 > 0:13:15if you have an internal combustion engine.

0:13:15 > 0:13:16Inside the engine,

0:13:16 > 0:13:19combustion of fuel creates hot gases

0:13:19 > 0:13:23and, when trapped, the pressure pushes the pistons

0:13:23 > 0:13:24and you're off!

0:13:24 > 0:13:27Engines happen to be one of my favourite things.

0:13:27 > 0:13:32They operate on what's known as the suck-squeeze-bang-blow principle.

0:13:32 > 0:13:36Air and fuel is sucked into the engine,

0:13:36 > 0:13:38they're squeezed in a chamber,

0:13:38 > 0:13:41and that mixture is then ignited by a spark.

0:13:41 > 0:13:44That's the bang which drives the pistons down.

0:13:44 > 0:13:50And, finally, the exhaust valve opens and that's the blow.

0:13:50 > 0:13:52We may think we're in control,

0:13:52 > 0:13:55but things can still blow up in your face

0:13:55 > 0:13:56if you're not smart about it.

0:13:56 > 0:14:01So don't try any of this at home.

0:14:05 > 0:14:07A note from our lawyers there.

0:14:07 > 0:14:11Now, obviously, without combustion, I wouldn't have a regular day job.

0:14:11 > 0:14:13But cars don't rely on engines alone.

0:14:13 > 0:14:17Another key chemical component is the battery -

0:14:17 > 0:14:21big, powerful, and occasionally prone to going flat.

0:14:21 > 0:14:24Why does it do that? Or...

0:14:29 > 0:14:31Imagine a world without portable electric power.

0:14:31 > 0:14:35The wiring would cause traffic chaos.

0:14:35 > 0:14:38Thank heavens for batteries.

0:14:39 > 0:14:43Batteries convert chemical energy into electricity.

0:14:43 > 0:14:46And they all work in a fairly similar way.

0:14:46 > 0:14:48Inside are two metallic plates,

0:14:48 > 0:14:50called electrodes.

0:14:50 > 0:14:53And between them is a sort of chemical bridge,

0:14:53 > 0:14:55called an electrolyte,

0:14:55 > 0:14:58made of stuff like sulphuric acid.

0:14:58 > 0:15:01And the electrolyte allows charged electrons gathered at one electrode

0:15:01 > 0:15:06to travel to the other, creating the get up and go.

0:15:06 > 0:15:10The transfer of electrons is the basic principle of all batteries.

0:15:10 > 0:15:14In fact, you could stick two electrodes in anything organic

0:15:14 > 0:15:16and create a current.

0:15:16 > 0:15:19Even a lemon, because the citric acid in the lemon

0:15:19 > 0:15:21would become the electrolyte.

0:15:21 > 0:15:24Trouble is, you'd need a lemon bigger than a car

0:15:24 > 0:15:26just to start the car.

0:15:31 > 0:15:33The lead acid batteries in our cars

0:15:33 > 0:15:35were the first rechargeable ones

0:15:35 > 0:15:37and haven't changed a great deal

0:15:37 > 0:15:39since 1859.

0:15:39 > 0:15:42But they're a bit of a chemical conundrum, as, really,

0:15:42 > 0:15:45they shouldn't work at all.

0:15:45 > 0:15:48Because their electrodes consist of lead at one end

0:15:48 > 0:15:50and lead oxide at the other.

0:15:50 > 0:15:52And oxides don't normally

0:15:52 > 0:15:53conduct electricity.

0:15:53 > 0:15:57So where does the juice come from?

0:15:57 > 0:16:01Well, it took us until 2011 to figure this out.

0:16:01 > 0:16:03When electrons travel

0:16:03 > 0:16:04between the electrodes,

0:16:04 > 0:16:06the lead oxide LOSES oxygen,

0:16:06 > 0:16:09transforming itself into a conductor.

0:16:09 > 0:16:12And away you go!

0:16:12 > 0:16:14All batteries will die at some point,

0:16:14 > 0:16:17because there is a limit to the chemical energy stored inside.

0:16:17 > 0:16:21Even the one inside your car will die eventually.

0:16:21 > 0:16:24Battery technology is getting better and better all the time.

0:16:24 > 0:16:26But there are still problems.

0:16:26 > 0:16:29They're expensive to manufacture, they're heavy to carry around,

0:16:29 > 0:16:32they're difficult to dispose of.

0:16:32 > 0:16:36One possibility for the future is to use things like hydrogen fuel cells.

0:16:36 > 0:16:38So, in the very near future,

0:16:38 > 0:16:41lead acid car batteries could seem like old news,

0:16:41 > 0:16:43but we can't really complain.

0:16:43 > 0:16:48After all, these ones have lasted over 150 years.

0:16:50 > 0:16:52Well, I, for one, look forward to the day

0:16:52 > 0:16:54when I don't have to ask my neighbour

0:16:54 > 0:16:58for a jump-start on a cold winter's morning.

0:16:58 > 0:17:01It's enough to drive you to drink. Not while you're driving, obviously.

0:17:01 > 0:17:06But that brings me on to another of chemistry's most popular creations -

0:17:06 > 0:17:09a pint, or a dram.

0:17:09 > 0:17:10Whatever your pleasure,

0:17:10 > 0:17:13one chemical formula is responsible for all of them.

0:17:21 > 0:17:25We've been making merry with alcohol since the Stone Age.

0:17:25 > 0:17:27You wouldn't recognise the stuff they drank,

0:17:27 > 0:17:30as it contained all sorts of strange substances,

0:17:30 > 0:17:32including narcotic herbs.

0:17:34 > 0:17:37But the way alcohol is made has never really changed -

0:17:37 > 0:17:40it's all thanks to fermentation.

0:17:40 > 0:17:43What's that?

0:17:43 > 0:17:50This is when the sugars in fruits, grains, potatoes, or even cactus

0:17:50 > 0:17:52are combined with water and yeast

0:17:52 > 0:17:53to form a mash.

0:17:57 > 0:18:00Yeast is one of the 15,000 or so members

0:18:00 > 0:18:03of the bizarrely named "kingdom of fungi."

0:18:03 > 0:18:08It's a micro-organism and we exploit it to encourage chemical reactions

0:18:08 > 0:18:12in the making of things like bread and cheese.

0:18:12 > 0:18:16Although I'm rather more interested in its boozy potential.

0:18:16 > 0:18:17Cheers.

0:18:20 > 0:18:22The yeast causes a chemical reaction,

0:18:22 > 0:18:25converting sugar molecules into ethanol-alcohol,

0:18:25 > 0:18:29and carbon dioxide - the bubbles.

0:18:29 > 0:18:32With lots of booze, we let the bubbles out,

0:18:32 > 0:18:35but in lager and Champagne, they're trapped.

0:18:36 > 0:18:39A bottle of bubbly contains millions of bubbles

0:18:39 > 0:18:42and exerts roughly three times more

0:18:42 > 0:18:44pressure than the air in a car tyre.

0:18:44 > 0:18:47And it's thought that those tiny bubbles

0:18:47 > 0:18:51speed the flow of alcohol into your bloodstream.

0:18:51 > 0:18:54If you want even more of a kick,

0:18:54 > 0:18:57you'll need one of these - a still.

0:18:57 > 0:18:58Distillation starts by heating

0:18:58 > 0:19:00the fermented alcohol,

0:19:00 > 0:19:02causing it to boil.

0:19:02 > 0:19:06Vapours then rise and are channelled into a condenser,

0:19:06 > 0:19:08where they cool back into a liquid

0:19:08 > 0:19:11with a much higher alcoholic content.

0:19:11 > 0:19:12This stuff is like rocket fuel,

0:19:12 > 0:19:16so it has to be watered down again before it's even bottled,

0:19:16 > 0:19:18let alone drunk.

0:19:18 > 0:19:21Alcohols are a family of different molecules.

0:19:21 > 0:19:24Methanol is the toxic alcohol.

0:19:24 > 0:19:26Methanol will make you blind.

0:19:26 > 0:19:29Isopropanol. This is commonly found as rubbing alcohol.

0:19:29 > 0:19:32So when you look on the side of your whisky bottle

0:19:32 > 0:19:35and it gives you a percentage, that's the percentage of ethanol

0:19:35 > 0:19:37and that's the bit that makes you tipsy.

0:19:37 > 0:19:42But whether you like your booze neat, fizzy, shaken or stirred,

0:19:42 > 0:19:44it's all just a chemical cocktail.

0:19:46 > 0:19:48One of the other things alcohol does

0:19:48 > 0:19:53is give us a distorted notion of our own attractiveness.

0:19:53 > 0:19:56And the false confidence to go and chat someone up.

0:19:56 > 0:20:00Now, this may work out in your favour, but, of course, it may not.

0:20:00 > 0:20:03So you should really consider alternative means

0:20:03 > 0:20:05of making yourself more appealing.

0:20:05 > 0:20:08Maybe chemistry could help us here, too.

0:20:10 > 0:20:15Can chemistry make me irresistible?

0:20:15 > 0:20:18One person you could have asked was a woman named Tapputi.

0:20:18 > 0:20:21She was the first recorded chemist, living in 1200BC,

0:20:21 > 0:20:24and extracted perfumes from

0:20:24 > 0:20:27flowers, herbs, even animal glands,

0:20:27 > 0:20:30all designed to make people more desirable.

0:20:30 > 0:20:33Today, we're able to synthetically mimic aromas,

0:20:33 > 0:20:36using complex chemical ingredients.

0:20:36 > 0:20:40Smell and taste are both parts of the body's amazing ability

0:20:40 > 0:20:42to detect chemicals.

0:20:42 > 0:20:47The receptors inside our noses respond to give rise to a signal

0:20:47 > 0:20:52and, in many cases, these compounds then smell pleasant to us.

0:20:52 > 0:20:57You might think perfumes are all designed to mask your body odour,

0:20:57 > 0:21:01but researchers claim we subconsciously choose a scent

0:21:01 > 0:21:03that complements it.

0:21:03 > 0:21:05Our natural odour contains pheromones -

0:21:05 > 0:21:09aromatic compounds released through sweat glands.

0:21:09 > 0:21:12Pheromones have less to do with love per se,

0:21:12 > 0:21:15and more to do with your immune system.

0:21:15 > 0:21:18Subconsciously, we're always on the lookout

0:21:18 > 0:21:21for someone whose immune system is different,

0:21:21 > 0:21:24because our offspring will inherit the best of both.

0:21:24 > 0:21:28All this chemistry is happening at a molecular level.

0:21:28 > 0:21:30But once the attraction becomes apparent,

0:21:30 > 0:21:35there are a few things you can do to heighten your chemical romance.

0:21:35 > 0:21:38Number one, go diving for oysters.

0:21:38 > 0:21:42They contain dopamine, which enhances your libido.

0:21:42 > 0:21:45Two, gorge on bananas.

0:21:45 > 0:21:50They contain zinc, said to increase sperm and testosterone production.

0:21:50 > 0:21:54And three, keep a bottle of mouthwash handy.

0:21:58 > 0:22:01Hydrogen sulfide lies on the back of your tongue

0:22:01 > 0:22:04and that's what gives you bad breath.

0:22:04 > 0:22:07Mouthwash kills it off, using a variety of ingredients,

0:22:07 > 0:22:11such as hydrogen peroxide, menthol, and, my personal favourite,

0:22:11 > 0:22:16alkyletholbenzyldimemmo... alkylbetholbenzyldimeldonium...

0:22:16 > 0:22:19This fella, here.

0:22:21 > 0:22:23That is a bit of a mouthful.

0:22:23 > 0:22:25If all that's led you to the bedroom,

0:22:25 > 0:22:27and you're still in need of help,

0:22:27 > 0:22:30there's a little blue pill containing sildenafil citrate,

0:22:30 > 0:22:34which, well, keeps the blood flowing for longer.

0:22:34 > 0:22:38But we'll leave that behind closed doors, shall we?

0:22:39 > 0:22:44But I wouldn't have to rely on fragrances and breath fresheners

0:22:44 > 0:22:47and aphrodisiacs if I were a billionaire, would I?

0:22:47 > 0:22:49HE CHUCKLES

0:22:49 > 0:22:51Fat chance of that happening...

0:22:51 > 0:22:57Unless I could find a way to turn lead into gold.

0:22:57 > 0:23:01Actually, chemists have been trying to do that for 2,000 years.

0:23:01 > 0:23:03I wonder if any of them ever managed it!

0:23:07 > 0:23:10To look at them, one glitters,

0:23:10 > 0:23:13while the other one is...well, rather dull.

0:23:13 > 0:23:18But gold and lead have some surprisingly similar qualities.

0:23:18 > 0:23:24Both are heavy metals, and both are malleable, especially when heated,

0:23:24 > 0:23:27which may be why alchemists have tried throughout history

0:23:27 > 0:23:30to turn one into the other.

0:23:30 > 0:23:31Without success.

0:23:32 > 0:23:34Actually, many alchemists died

0:23:34 > 0:23:37as a result of breathing in poisonous fumes

0:23:37 > 0:23:39while trying to turn lead into gold.

0:23:39 > 0:23:43And even the man who discovered gravity, Sir Isaac Newton,

0:23:43 > 0:23:44he dabbled in alchemy

0:23:44 > 0:23:48and he suffered mercury poisoning towards the end of his life

0:23:48 > 0:23:52as a result of his more...chemical hobbies.

0:23:52 > 0:23:57But in the 1970s, Russian scientists unexpectedly discovered

0:23:57 > 0:24:00that part of the lead shielding in their nuclear reactor

0:24:00 > 0:24:02had, astonishingly,

0:24:02 > 0:24:04turned into gold.

0:24:04 > 0:24:08The secret, it seems, is radiation.

0:24:08 > 0:24:12The atomic number of gold is 79,

0:24:12 > 0:24:14while lead is 82.

0:24:15 > 0:24:19And if you zap lead with radiation, it causes an energy build-up,

0:24:19 > 0:24:21some of which has to be released.

0:24:21 > 0:24:24The result is that lead loses some of its protons.

0:24:24 > 0:24:27And if you're lucky, presto,

0:24:27 > 0:24:30you get gold!

0:24:30 > 0:24:33Sounds easy, but here's the catch.

0:24:33 > 0:24:35The gold would be so radioactive,

0:24:35 > 0:24:38you'd be dead before you could bank it.

0:24:38 > 0:24:40It turns out, though, we need gold

0:24:40 > 0:24:42for far more than just bling.

0:24:42 > 0:24:44It's also a fantastic conductor

0:24:44 > 0:24:48and is found in all manner of electronic devices.

0:24:48 > 0:24:51You have a cellphone, guess what? Your cellphone's full of gold.

0:24:51 > 0:24:55Not enough to make a gold ring, but the circuits inside your cellphone

0:24:55 > 0:24:57are connected together with gold wire.

0:24:57 > 0:24:59Gold is highly conductive.

0:24:59 > 0:25:01It's able to give up its electrons

0:25:01 > 0:25:03and pass these electrons through the material

0:25:03 > 0:25:05so that it can conduct electric current.

0:25:05 > 0:25:07And other metals are less good at that,

0:25:07 > 0:25:10because they hold on to their electrons more tightly.

0:25:10 > 0:25:14Gold is expensive - can chemistry give us an answer? Chemistry can.

0:25:14 > 0:25:17Now science is trying to use nanotechnology

0:25:17 > 0:25:21to manipulate the electrons on the surface of base metals, like lead,

0:25:21 > 0:25:24to make them behave like their precious counterparts.

0:25:24 > 0:25:28It might not be exactly what the alchemists had in mind,

0:25:28 > 0:25:33but it's still lead into gold, sort of.

0:25:34 > 0:25:38The other age-old quest those ancient alchemists

0:25:38 > 0:25:40were eternally pre-occupied with

0:25:40 > 0:25:43was to find the potion to give eternal life.

0:25:43 > 0:25:46I wonder if chemistry could crack that nut as well!

0:25:49 > 0:25:54THIS is chemistry's holy grail - the elixir granting eternal youth.

0:25:54 > 0:25:57Unfortunately, despite plenty of searching throughout the ages,

0:25:57 > 0:26:00we haven't found it...yet.

0:26:00 > 0:26:03But we have discovered chemicals that may help

0:26:03 > 0:26:05to keep death at bay for a little longer.

0:26:05 > 0:26:08The goal is to extend life by repairing the damage

0:26:08 > 0:26:11that our cells are subjected to over time,

0:26:11 > 0:26:14which is the cause of dreaded old age.

0:26:14 > 0:26:17One of the mechanisms of ageing is that the genes -

0:26:17 > 0:26:20part of your genetic code -

0:26:20 > 0:26:23as cells split and duplicate,

0:26:23 > 0:26:26the genes are transmitted from cell to cell,

0:26:26 > 0:26:28but they get shorter and shorter and shorter.

0:26:28 > 0:26:32And over time, you can start to notice their effects.

0:26:32 > 0:26:33And that's what we call ageing.

0:26:33 > 0:26:38Among the most promising candidates found so far are sirtuin activators,

0:26:38 > 0:26:41proteins that trick the body into thinking

0:26:41 > 0:26:43it doesn't need any more calories.

0:26:43 > 0:26:46So why is that a good thing?

0:26:46 > 0:26:48Well, these proteins can defend

0:26:48 > 0:26:51against a major contributor

0:26:51 > 0:26:53to cell damage - overeating.

0:26:53 > 0:26:55When excess calories flood your system,

0:26:55 > 0:26:59it causes your cells to age at a faster rate.

0:27:00 > 0:27:03But to the rescue comes red wine,

0:27:03 > 0:27:05full of a sirtuin activator

0:27:05 > 0:27:07called resveratrol,

0:27:07 > 0:27:10a chemical produced by the grapevine

0:27:10 > 0:27:13in times of starvation or stress.

0:27:13 > 0:27:15And studies have found

0:27:15 > 0:27:19that resveratrol extends the life span of its test subjects, mice,

0:27:19 > 0:27:21by as much as 50%.

0:27:24 > 0:27:26Which might explain why the French,

0:27:26 > 0:27:30for all their love of both rich food and red wine,

0:27:30 > 0:27:33still live as long as the rest of us.

0:27:35 > 0:27:39Other anti-ageing remedies aren't quite so appealing, though.

0:27:39 > 0:27:43Rapamycin, for example, is an anti-fungal agent

0:27:43 > 0:27:46found only in the soil on Easter Island.

0:27:46 > 0:27:50And, supposedly, it can slow the ageing process.

0:27:50 > 0:27:53Don't really fancy eating soil, though.

0:27:54 > 0:27:58So enjoying a glass a day might actually keep the doctor away.

0:27:58 > 0:28:04But don't overdo it. Otherwise, it might be the booze that kills you.

0:28:04 > 0:28:07Finding the elixir of eternal youth

0:28:07 > 0:28:11is unlikely to be something that happens in my lifetime.

0:28:11 > 0:28:15But chemistry has always given us the power and the confidence

0:28:15 > 0:28:18to solve problems and even dream the impossible.

0:28:18 > 0:28:22And you can rest assured that that's not likely to change.

0:28:22 > 0:28:25And who knows? Maybe one day, they'll come up with a formula

0:28:25 > 0:28:29that helps us remember everything we learned in chemistry class.

0:28:29 > 0:28:31I'd have some of that.

0:28:52 > 0:28:56Subtitles by Red Bee Media Ltd