Air we breathe: Air Composition Composition of clean & polluted air Before you can understand air pollution, you need to have an understanding of clean air. Composition of Clean Air In the fall of 2002 I got to go to Switzerland. On the morning of November 6th, I had to leave the village of Zermatt, but wanted to take one more look at the Matterhorn. The air was absolutely clear. Cleaner than I have ever seen air anywhere. The Matterhorn jumped out at you. By the way, Zermatt does not allow automobiles. People walk or ride electric vehicles. The train that goes there and the trolley that takes you to the ski lifts also run off of electricity. Here are 10 gases that make up clean air: In order of highest to lowest concentration they are Nitrogen, Oxygen, Argon, Carbon dioxide, Neon, Helium, Methane (CH4), Krypton, Hydrogen, and Xenon. Five of them travel alone, so we call them atoms. For example, a helium balloon contains atoms of helium (He), but an oxygen tank contains molecules of oxygen (O2). When there's two or more atoms are bonded together, they are called molecules.

NITROGEN (N2) #1: 8 out of 10 atoms (or molecules) of air are made of nitrogen. Nitrogen gas can't be seen but when it is cooled to -320 °F (-195°C) it turns to a liquid, which you can see. Being this cold makes it handy for many things. Shown here, it is being used to quickly freeze cream and sugar to make ice cream. NITROGEN #2: Liquid nitrogen is also used to cool certain metals to the point where they become superconductors. Superconductors conduct electricity (electrons) without any resistance. In this picture a rectangular shaped magnet had been dropped onto a metal disk that had been cooled enough so that it was a superconductor. As the magnet fell toward the metal disk, the magnetism in the magnet caused currents of electricity to flow inside the metal disk. The currents created in the metal disk by the falling magnet made that part of the metal disk a magnet itself. The falling magnet then feels the repulsion of the magnet it just created. The falling magnet will then stop just above the metal disk.

Electricity continues to flow in the metal disk constantly creating a mirror image magnet that repels the real magnet. This will continue forever as long as the metal is cool enough to stay a superconductor. NITROGEN #3: Oxygen reacts with many things including paint. Therefore, expensive works of art and other rare relics are stored in pure nitrogen. Nitrogen gas is fairly inert and doesn't react (combine) with most other substances, so it is used to protect items and keep oxygen away.. Bad Nitrogen NITROGEN goes bad: Under high temperatures, like in a jet engine or car engine, nitrogen will combine with oxygen to form a class of toxic compounds called nitrogen oxides. The simplest having one nitrogen and one oxygen (NO). Others have two nitrogens and one oxygen (N2O), one nitrogen and two oxygens (NO2), and the fourth has two of each (N2O2). Their names (in order) are nitrogen oxide, dinitrogen oxide, nitrogen dioxide, and dinitrogen dioxide. Nitrogen dioxide has a brownish appearance and is often what you see in polluted cities. Oxygen #1: 2 out of 10 atoms/molecules of air is oxygen.

Oxygen is produced by plants and is consumed by animals. Animals need oxygen to "burn" the food they eat in order to get the calories (energy) they need. The way animals use oxygen to burn food is different than a fire, but it produces the same products of carbon dioxide and water. Of all of the gases that make up air, oxygen is the most reactive. Oxygen is Everywhere in This Photo OXYGEN #2: Oxygen is everywhere. As a gas it makes up 20% of the air. Some oxygen gas is dissolved in water, and some oxygen gas is in the pores in the ground. However, there's a lot more oxygen in this picture that we don't normally consider. 90% of the weight of the water in the river is oxygen atoms. Remember water is H2O. The one oxygen in H2O weighs 8 times has much as the two hydrogen atoms combined. The trees and grass are made of carbon, oxygen, hydrogen, and nitrogen, with oxygen accounting for about half of a plant's weight. The rocks, the soil, and the mountains contain metals and silicon that is bound to oxygen, which makes up about 1/2 of their weight.

Think about it; one half of a mountain's weight is from oxygen. The only thing in the picture that doesn't contain oxygen are the metal rails. OXYGEN #3: In the movie Total Recall, there was an ancient alien factory that could release the oxygen from the Martian soil. This is actually possible. Extreme heat will cause the oxygen to separate from the metals and non-metals that it was bound to. Most of Martian soil is iron oxide, which would turn to iron metal and oxygen gas at high temperatures. In the pictures above, Arnold presses the touch sensitive on "button" of the oxygen generator. Next he gets blown out of the factory into the thin Martian air, which causes the air in his body to expand. Fortunately, the oxygen rushes out of the top of the mountain that housed the factory and they show Mars getting an atmosphere similar to Earth's. Actually, this atmosphere would be pure oxygen, which is not good to breath for long periods and would present extreme fire hazards. It's lacking the 80% nitrogen. ARGON: Argon is 1 out of 100 atoms/molecules of air. Argon is an inert gas that is used to pressurize light bulbs.

Being inert it doesn't react with the tungsten metal, which makes the filament. The argon gas also helps keeps the tungsten metal atoms on the surface of the filament from jumping off the filament. Argon gas is also used in welding to push away the air so that the oxygen in the air won't react (oxidize) the metal being welded. CARBON DIOXIDE: Carbon dioxide only makes 3 out of 10,000 atoms/molecules of air; however, it supplies the carbon that plants use to make leaves, trunks, roots, etc. It's hard to believe that the weight of giant redwood trees came from the small amount of carbon dioxide gas in the air. NEON: 2 out 100,000 atoms/molecules of air. Neon is a clear inert gas; however, high voltage can strip electrons off neon atoms. As the electrons fall back into place, they give off ultraviolet light (black light), which you can't see. However, the glass tubes are coated with different phosphor powders, which glow when ultraviolet light hits them.

HELIUM: 5 out of 1,000,000 atoms or molecules of air are helium. Helium is the second lightest gas (hydrogen is lightest). It is used to fill toy balloons and weather balloons. It is so inert that there is no danger of igniting nor will it combine with other elements. For this reason it is used in welding by having helium gas surround an electric arc that is melting a metal. The flow of helium gas keeps the oxygen away from the metal so that the oxygen won't oxidize (rust) the metals being welded. METHANE: 2 out of 1,000,000 atoms/molecules of air are methane molecules. Bacteria is a big source of methane gas and this type of bacteria is found in termites (see huge termite mound on the left), cattle (cow flatulence), rice paddies, swamps (called swamp or marsh gas), and in the sea bed. In the sea bed, methane can be found trapped in ice (see person holding ice that's on fire). Methane also comes from petroleum fields and is the natural gas you cook with. An embarrassing source of methane is from the eating of beans.

KRYPTON: 1 out of 1,000,000 atoms/molecules of air is krypton gas. You may remember krypton as the name of the planet that Superman came from. The pieces of the planet that fell as meteorites were called kryptonite. The element krypton is used in lamps in a similar way that argon is used (see above). The word krypton comes from "Krypto" meaning hidden. The gas krypton was in a way hidden because it took quite a while for scientists to discover it. HYDROGEN: 1 out of 2,000,000 atoms/molecules of air is hydrogen. Hydrogen is the lightest element, which is why is was the preferred gas to fill blimps and dirigibles. Unfortunately, hydrogen is very flammable, which led to the catastrophic tragedy of Germany's Hindenberg airship. XENON: 87 atoms out of 1,000,000,000 (one billion) atoms/molecules of air are xenon. Like argon and krypton, xenon is used as the gas in lamps. This one is for a car's headlamp.

These are probably the ones that look more blue. WATER VAPOR: The other gas we didn't list before is water vapor. The concentration of the other gases are pretty consistent, but water vapor varies greatly. Using a fish-eye lens, I took this picture of a double rainbow in Geneva, Switzerland. It had rained all day, but just before the sun went down, the clouds parted enough to allow the sunshine to strike the droplets of liquid water still in the air. Water in vapor form (gas) is not visible. One Last Look at Composition of Air: Imagine the volume of air in a typical classroom that is 30 feet by 30 feet with a 10 foot high ceiling. Also assume, we separated all the gases. Oxygen would cover the room to about 2 feet deep. Nitrogen would fill almost to the ceiling (another 8 feet minus a couple of inches). Argon gas would fill a one inch layer over the whole room. The remaining gases fill the last one inch. Carbon dioxide has about the same volume of one student. Neon is 1.5 gallons. Helium would fill a one liter bottle. Methane gas would fill someone's 1/2 liter bottle.

Krypton would fill a 12 oz soda can. Hydrogen would fill about half of a 12 oz soda can. And xenon gas would have the volume of a pencil's eraser. Composition of Polluted Air Particulates Part of the below tutorial is from Lab 1 (Air We Breathe) The image on the left is from one of the dust storms that hit Mesa and Phoenix. We all know that breathing that dust will be bad for us. Even on days without a dust storm, there are plenty of particulates in the air which aren't healthy. Surprisingly, it's not just what the particulates are made of, but the size of the particulates that also affects its effect on the lungs. Note: In this context, "particulates" mean solid particles that are suspended in the air. The lungs contain thousands of sacs called alveoli. This is where oxygen passes through the lining of the alveoli and enters the blood. This is also where carbon dioxide leaves the blood. Our nose hairs and mucous in the nasal passages and the bronchial tubes try to block particles that we breath in.

However, if the particles are too small, they get by these defenses and get to the alveoli. If the particles are even smaller, they pass through the lining of the alveoli and even get into the blood stream. (See image below) The human hair is about 70 to 100 millionths of a meter in diameter. A millionth (micro) of a meter is called a micrometer or micron for short. The symbol for a millionth (micro) is µ. So the human hair is 70µm to 100µm in diameter. Particles over 10µm are usually trapped by nose hairs and mucous in the nasal passages. So their danger is less. However, particles between 10µm and 2µm get past those defenses and get deep into the lungs. These are such things as dust particles, mold, mold spores, and pollen. They can irritate the lungs and cause severe reactions. Smaller particles (0.1µm to 2.5µm) are small enough to pass through the lung lining and enter the blood stream and reach all organs of the body. As you might guess, this can cause even greater health issues.

These smaller particles can be soot (from combustion of wood, gasoline, diesel, etc.), aerosols (from sulfuric acid forming in the atmosphere and reacting with other particles), and finely powdered metal (from car brake pads, metal sanding, etc.). The air inside and outside our home contains numerous particulates (particles suspended in the air). Below are some, plus their size in microns. Anything under 10 microns is not visible to the eye and is more hazardous. By the way, dust mites live in your bedding and pillows. They eat the flakes of skin that you shed. Human Hair .................(70 - 100 microns) Pet Dander ..................(0.5 - 100 microns) Pollen ...........................(5 - 100 microns) Dust Mite Debris ........ (0.5 - 50 microns) Household Dust .......... (.05 - 100 microns) Skin Flakes ...................(0.4 - 10 microns) Bacteria....................... (0.35 - 10 microns) As you can see, most of these dip down into the unhealthiest range of under 2.5µm.

As a defense, filters are employed to trap these particles. You may have heard of HEPA filters for vacuum cleaners and room air filters. HEPA stands for "High Efficiency Particulate Arresting". Arresting meaning stopping. These filters were first used to capture radioactive particles in the air at the facility where the first atomic bomb was being built. HEPA filters will only miss 3 out 10,000 particles 0.3 microns in size. For larger size particles, it misses even fewer of them. It uses a mesh of fibers to accomplish this. Fibers can be made from plastic, glass, or cellulose (like cotton fibers). The fibers actually have openings much larger than the particles that it can capture. So it doesn't act like a sieve that can only capture particles larger than the sieve openings. As particles move through the fiber mesh, they get wedged in the narrow spaces where the fibers cross each other. The faster moving air actually helps particles get wedged in between fibers. That's probably why it is called High Efficiency Particulate Arresting. Of course, particles larger than the openings will get caught between the fibers.

They call these mechanical filters because the particulates are mechanically held (blocked or wedged) in the filter. This is a granule of activated charcoal. The pits seen are about 100 microns in size; however, these are the large pits. There are others thousands of times smaller. So activated charcoal can act as a mechanical filter by blocking particles larger than its smallest pores. However, it can also trap certain substances that are so small that they can pass right through the pores. Activated charcoal does this because certain substance are attracted to the surface of the carbon. In other words, the carbon in activated charcoal acts like fly paper to certain substances. Vapors from solvents like gasoline or paint thinner stick to the surfaces and are trapped. They call this adsorption (spelled with a "d"). Absorption (spelled with a "b") is when a thing soaks into something. Adsorption is when it sticks to its surface. This is the famous brown air of Phoenix. It's appearance is from a mixture of dust, smoke, other particulates, and nitrogen dioxide (which is brown).

Smoke from wood fires: The smoke from a campfire or from a forest fire is quite dangerous partially because of the abundance of very small particles that are in the smoke. Most particles in wood smoke are smaller than the 2.5 microns (2.5µm). These particles don't normally get coughed up. They are so small that they get stuck into the lining of the alveolus sacs. Perhaps the most dangerous component of wood smoke is the countless airborne particles (particulates). Airborne particles smaller than 2.5 microns are harmful because they are tiny enough to lodge inside lung tissue, while particles larger than 2.5 microns are coughed out. Researchers have discovered that the particles found in wood smoke are almost all smaller than 2.5 microns. Nonfatal heart attacks Some cancers One place to find particulates in the air is to look for what particulates have settled out of the air and onto our cars. In the dry climate in Arizona, particulates are not washed out of the air from rain, so cars get dusty pretty quickly. Also, the car seems to accumulate more road grime and dust when it's driven on the highways and streets.

A few cars filter the air coming through the vents, but that still doesn't help when you roll down the windows. Again, most cars don't have a car cabin air filter. SAMPLE OF OUTDOOR PARTICLES: Below is a sample taken from a dusty car using clear tape. What is mostly seen are lot of small particles of clear silica (sand/quartz). The photo doesn't show how clear these little particles appear. Also, the few cylindrical particles present look like pieces of plant material. When there was white paper behind the tape, many small black particles were seen. They, again, are likely soot particles and even particles from tires. So outside seems to have more mineral dust, more soot, and tire particles. POLLEN: Pollen is one of the common particulates in the air. For people with allergies, pollen is one of the biggest triggers of allergic reactions. Pollen is stored on the anthers, which sit on the ends of stalks called filaments. The yellowish white spheres are pollen. The tiny white specks that you see in the photo are just adhesive from the tape that was used to capture the pollen. DUST from SOIL: Fine particles in dirt are often blown into the air by wind and vehicles.

Dust from soil is one of the common particulates in the air, especially in Phoenix and the surrounding area. The soil sample collected shows a variety of minerals. Many are too large to get airborne, but the smaller ones can become dust pollution. Soil is mostly quartz with hundreds of other minerals. The darker grains are likely iron oxides or silicon dioxide (quartz) with iron or magnesium impurities. Soil will also have some pieces of plant material. None is that noticeable in this photo. Some soils are rich in organic (plant) materials, but Arizona soil doesn't have that much plant material in its soil. Here is the same sample without the white paper background. You can see that it changes the look of the particles. The lighter particles stand out more. The grains of minerals have a rough look. They also look clear, white, black, or may have some color in it. If it is a bright color, then it is probably not a mineral, perhaps a paint chip or piece of some insect. SOOT and SMOKE: The other particles that are often seen in air samples are carbon particles (soot). These come from unburnt gasoline and unburnt diesel.

Fireplaces also put out a lot of soot, but fortunately in Phoenix fireplaces aren't used that much. Forest fires also put out a tremendous amount of ash and soot. So it's just not the fire that is dangerous about a forest fire; it's the smoke. When we think of diesel smoke, we usually think of the large semi trucks. However, there are thousands of pickups that have diesel engines just in any one city. The small trucks also put out diesel smoke. Not as much as the large trucks nor as much as the truck in this photo. Rather sadly, some diesel truck owners actually program their truck's microcontroller to produce these large amounts of smoke when they want to. Nearly every school bus runs on diesel also. If the engines are cold, old, or not properly tuned, then a lot of diesel smoke gets breathed by school children around that bus. The ultimate air pollution happens when a person smokes. The smoke is deliberately inhaled deep into the lung. The very small particles of smoke penetrate into the lung tissue. This is a section of lung tissue from a smoker. You can see how the carbon particles get lodged around the alveoli.

Gasoline engines also put out soot especially if the gasoline to air mixture is rich (too much gasoline). The inside of a tailpipe of a car is a good place to find carbon particles (soot). Here is the sample from the tail pipe. Soot formed from unburnt gasoline or diesel are very small particles. They look like tiny black or gray specks under the microscope. In extreme magnification, they look like spheres. The reddish color in this image is probably from rust particles (iron oxides) coming from metal in the exhaust system. As mentioned before, the small size of these smoke particulate make them more dangerous because they can lodge in the alveoli of the lungs. Some ash particles from cigarettes or burning wood can be larger than the typical soot particles. They are also black or dark gray. Some have a bluish tint. These ashes in the photo were caught in a wad of cotton using an air pump. The strands are the cotton fibers. Again, the larger particles are normally caught by the nose or sinus. Unfortunately, smoking means the smoke goes directly into the mouth where there is little filtering. So it gets into the lungs without much stopping it.

FIBERS: The air we breathe also has a lot of fibers and hairs in it. These short strands of fiber are from such things as clothes, rags, carpet, and paper towels. The hairs may be from pets or people, and even insects. Cotton fibers look like flat ribbons that got twisted. These are cotton fibers at 250x magnification. Synthetic fibers like nylon, polyester, and others are more round than cotton fibers. This magnification is about 100x. Long fibers don't get in the air easily. It's the short ones that we often breathe. This photo was shown above. The fibers that are more bent and twisted are likely cotton fibers. These have color because they are dyed cotton. A few fibers are less bent. Those are likely synthetic fibers. On the left is a synthetic fiber at about 250x magnification. Notice is it is not flat and twisted like cotton fiber. You can see some turquoise dye on (or in) the fiber. On the right is a strand of human or animal hair. Human and animal hair have a channel that runs through the middle of it. In high magnifications, scales on the outside of the hair can be seen.

DANDER AND DANDRUFF: Both dander and dandruff are pieces of dead skin. Dander normally refers to the dead skin that comes off of animals like pet dogs and cats. Dandruff is dead skin from the scalp. Dandruff is usually larger and flatter than dander. If you are interested in more information about microscopy, you can visit the website developed by the National High Magnetic Field Laboratory at the Florida State University. What gases are in the air we breathe? | Reference.com What gases are in the air we breathe? A: Quick Answer In dry air that does not contain pollution, the predominant gas is nitrogen, which makes up 78 percent of the atmosphere. The next two most voluminous gases are oxygen (21 percent) and argon (1 percent). Other gases appearing in trace amounts include carbon dioxide. Full Answer The air naturally contains water vapor as well. The proportion of water vapor in the area varies widely between different areas, depending on the climate. Human activity has had a significant impact on the gases in the atmosphere, particularly through the burning of fuels and the production of pollutant gases. Burning fossil fuels sends a great deal of carbon dioxide into the atmosphere.

Other gases that enter the atmosphere as pollution include sulfur dioxide, nitrogen oxides and carbon monoxides. When fuels do not burn completely, they send solid particles, as with carbon, directly into the air, causing a dirty film to form on buildings and on the inside of lungs. Carbon monoxide is one of the most toxic by-products among these pollutants. Inhaling carbon monoxide can lead to death. However, the other pollutants also are caustic to the environment; sulfur dioxide leads to acid rain, which can maim or even kill crops, trees and other plants. What are the ingredients in the air we breathe? | Reference.com What are the ingredients in the air we breathe? A: Quick Answer The air humans breathe is made up of about 78 percent nitrogen, 21 percent oxygen, and 1 percent carbon dioxide and argon. Trace gases include krypton, methane, neon, helium and hydrogen. Air generally contains trace amounts of water vapor, as well, with greater concentrations occurring near sea level. Full Answer While the large amount of nitrogen in the air usually has no effect on humans, in some cases it can become extremely dangerous.

When a diver breathes air deep underwater where pressures are high, the excess nitrogen forces its way into the bloodstream. When the diver ascends, the nitrogen can work its way back out slowly and be exhaled. If he ascends too rapidly, however, the nitrogen comes out of solution in his blood, causing intense pain and muscle spasms. Untreated, decompression sickness can be fatal. The nitrogen in normal air can also act as a narcotic under pressure. For this reason, divers who descend into deep water typically use a carefully regulated mix of oxygen and helium to prevent dizziness, drowsiness and a loss of coordination. During the early days of the Apollo program, NASA experimented with a pure oxygen atmosphere for its astronauts. Unfortunately, pure oxygen creates a highly flammable environment, and an accident during testing led to the deaths of the Apollo 1 crew. Since then, space agencies have used a mix of gases similar to the air found on Earth to prevent accidents. B.C. Air Quality What is Air? Air is a precious resource that most of us take for granted. Air supplies us with oxygen, which is essential for our bodies to live. Without it, we would die within minutes.

Pure air is a mixture of several gases that are invisible and odourless. It consists of about 78% nitrogen, 21% oxygen, and less than 1% of argon, carbon dioxide, and other gases — as well as varying amounts of water vapour. Adults breathe in about 10-20 cubic metres of air every day. That’s about 20,000 breaths. Children breathe almost twice that amount because they are smaller, and their respiratory systems are still maturing. What is the Atmosphere? The atmosphere is a mixture of gases that surround the earth. It is the air we breathe, the wind and rain, and the clouds in the sky. It is life giving, retaining heat and blocking out harmful rays (ultraviolet radiation) from the sun. The atmosphere is about 1,000 kilometres thick, and is made up of invisible layers that circle the planet. We live in the lowest and thinnest layer, called the troposphere, which is only about 14 kilometres thick. The bottom two kilometres of the troposphere are really our “home.” Most of the air and weather are there, along with most air pollutants. Two kilometres aren’t very much.

It would take just two minutes to drive that distance, at 60 km per hour. Above the troposphere is the stratosphere. This is the relatively quiet, stable band of air in which the ozone layer is found and where our emissions of greenhouse gases and ozone-depleting substances go. There is no exact place where the atmosphere ends; it just gets thinner and thinner, until it merges with outer space. In this section: What is Air Made Of? - Your Lungs and Breathing - Explore Your Body - Microbe Magic The air you breathe is made up of lots of other things besides oxygen! Oxygen only makes up about 21% of air. About 78% of the air you breathe is made up of another gas called nitrogen. There are also tiny amounts of other gases like argon, carbon dioxide and methane. Plant and animal life on earth can’t survive without air. Take a deep breath and click on Find Out More to find out more! Gas Facts for Kids - Science for Kids Worksheets Interesting Facts about Gases for Kids Gases are all around us, and most of them we don’t even know are there; we can’t feel them and most of the time we can’t see them either.

Read on to find out all about amazing gases and what they do! What are Gases? Gases are air-like substances that can move around freely or they might flow to fit a container. They don’t have a shape either. You could put your hand through gases and you wouldn’t feel a thing. If they get out a container they spread very easily. Gases are all around us in the air that we breathe. You certainly can’t put a gas into a measuring cup to measure its volume; there is a rather complicated mathematical formula that you’d have to use in order to figure this out. Their molecules are spaced apart and jiggle around. Molecules form every time two atoms join together. We know that gases are all around us, but some such as perfume for example you can smell, but most of the time they are invisible. Similar to liquids, gases can actually flow, but gases won’t stay put as solids or liquids do. They move around all the time. They also expand in every direction to completely fill whatever they’re put into. If the container has no lid, well say goodbye to them, they’re out of there. What types of Gases do you get? There are quite a few types of gases.

Pure gases are made up of just one atom, and Neon is an example of a pure gas. Then we get elemental gases. These are made up of two or more of the same atoms that have joined together. Hydrogen is an elemental gas. Compound gases come next and they have a combination of different atoms. Carbon monoxide is a compound gas. The air we breathe is made up of different types of gases. There is approximately 78% nitrogen, 21% oxygen with 1% argon and a couple of other gases too. Natural gas is another type of gas and has mostly methane inside of it. It is used to create electricity and is often used inside homes for heating and cooking, amongst other things. Noble gases are a group of chemical elements that are very stable under normal conditions. Naturally occurring noble gases include helium, neon, argon, krypton, xenon and radon. The ozone layer that protects Earth from the Sun’s damaging UV light is made up of ozone, an oxygen allotrope, which is a form of the same element but they have different properties. The ozone contains 3 oxygen atoms that are bound together.

Nitrous oxide is a gas with interesting properties that can be used in different ways, these include an anaesthetic in hospitals, the same as laughing gas, and they’re also used to increase the power of engines in motor racing. Interesting Facts about Gases Now this is gob-smackingly amazing. Gases move around at 1,600kmpm. That is seriously fast. A plane travels at about 885kmph, so gases go way, way faster than that! When gas particles crash into each other, the forces between them aren’t strong enough to keep them together…they would rather not be too friendly and bounce away from each other. Vapour is actually a gas that has evaporated, which means that water particles have escaped the Earth’s surface and gone back into the atmosphere. As an example, water actually forms a gas when it’s boiled to 100⁰C. But even at much lower temperatures, some of the water escapes from the liquid to form vapour. This mixes with the air. When vapour cools down a bit, the gas forms droplets and we’ll see mist. Pretty interesting stuff. Gas expands.

If you think about a hot air balloon, there is a burner inside which heats the air. The particles get heaps of energy and they move faster and faster and move further apart from each other, and push at the sides of the balloon. Heat always causes gases to expand, or grow. If you left a balloon near a fire, the air inside would expand so much that the balloon would give you a mighty pop as it bursts. Then there’s pressure. Have you ever wondered why a champagne cork explodes out of a shaken bottle when your parents are celebrating something? Well inside the bottle there are loads of bubbles, which are a gas. When the bottle gets shaken it releases the gas, and the gases that are moving at a rapid rate bang against the cork. So what does this cause? A lot of pressure on the cork, and eventually it comes hurtling out of the bottle. Wow, so now you know why this happens. The helium balloons you get at parties, well the reason they float is because helium is lighter than air, and of course helium gives you a crazy, wacky voice too. Natural gas was formed deep under the earth about 100 million years ago. Gases are certainly interesting things.

Learn these amazing facts and whizz through that next Science test you get. You’ll have one happy teacher! What is Medical Grade Air? What is Medical Grade Air? Written by Dan Chisholm Jr. on Thursday, 26 April 2012. Posted in News Medical Air is a colorless, odorless, and tasteless gas that is similar in composition to the air that we breathe. It is made up of approximately 78% Nitrogen and 21% oxygen with traces of water vapor, carbon dioxide, hydrogen, argon, and other various components. Medical air USP is used either by itself (i.e. to transport inhaled medications) or mixed with other gases to support patient respiration. The main use of medical air is to aid in long-term life support as in intensive care units, critical care units, and neonatal intensive care units. Medical air cannot be used for anything other than human respiration or the calibration of equipment used in human respiration. Chemically, since medical air is similar to the air around us, it exhibits essentially the same qualities as well. It will aid in combustion, but is not as much an accelerant as pure oxygen.

As with all compressed gases, care should be taken when handling, storing, or transporting. Medical air is utilized in high pressure cylinders or it can be manufactured onsite with air compressor systems at health care facilities. Medical Grade Air USP is the only pharmaceutical drug that is manufactured onsite and administered at health care facilities. When manufactured with compressor systems onsite, clean, contaminant free air is brought into the facility, then it is compressed, cooled, dried, filtered, and distributed through a medical gas pipeline distribution system. Medical Grade Air USP is utilized in the most critical care areas of the hospital and used by patients who are the most reliant on the medical staff for survival. The medical uses of medical air include: Transportation of inhaled medications. Transportation of inhaled anesthetic agents Surgical operations and procedures while patients are under anesthesia Mechanical ventilation for treatment of respiratory depression Drive gas for power to the bellows of critical care ventilators Medical Grade Air USP is administered by ventilator, face mask, nebulizer, endotrachial tube, NICU Chamber. The use of a pressure compensated flow meter is used to control the rate of flow desired.

Designated Color (USA & NFPA): Yellow Background with Black Lettering Recognized Designations: Medical Grade Air, Medical Air, Medical Air USP, Med Air, Air, MA, A CGA Connection Type: Air Composition Air Composition Dry air is a mechanical mixture of nitrogen, oxygen, carbon dioxide and more Sponsored Links Air is a mixture of gases - 78% nitrogen and 21% oxygen - with traces of water vapor, carbon dioxide, argon, and various other components. Air is usually modeled as a uniform (no variation or fluctuation) gas with properties averaged from the individual components. Gas Ratio compared to Dry Air (%) Molecular Mass 165.1 -108.1 The water or vapor content in air varies.

The maximum moisture carrying capacity of air depends primarily on temperature The composition of air is unchanged until elevation of approximately 10.000 m The average air temperature diminishes at the rate of 0.6oC for each 100 m vertical height "One Standard Atmosphere" is defined as the pressure equivalent to that exerted by a 760 mm column of mercury at 0oC sea level and at standard gravity (32.174 ft/sec2) Other components in air Sulfur dioxide - SO2 - 1.0 parts/million (ppm) Methane - CH4 - 2.0 parts/million (ppm) Nitrous oxide - N2O - 0.5 parts/million (ppm) Ozone - O3 - 0 to 0.07 parts/million (ppm) Nitrogen dioxide - NO2 - 0.02 parts/million (ppm) Iodine - I2 - 0.01 parts/million (ppm) Carbon monoxide - CO - 0 to trace (ppm) Ammonia - NH3 - 0 to trace (ppm) Common Pressure Units frequently used as alternative

 to "one Atmosphere" 76 Centimeters (760 mm) of Mercury 29.921 Inches of Mercury 14.696 Pound-Force per Square Inch 2116.2 Pounds-Force per Square Foot 1.033 Kilograms-Force per Square Centimeter 101.33 kiloPascal More about Temperature, Density, Specific heat, Thermal Conductivity - the properties of air.

Related Topics Air Psychrometrics - The study of moist and humid air - psychrometric charts, Mollier diagrams, air-condition temperatures and absolute and relative humidity and moisture content Material Properties - Material properties for gases, fluids and solids - densities, specific heats, viscosities and more Sponsored Links Related Documents Specific Heat Ratio of Air - Specific Heat Ratio of air at temperatures from -40 - 1000oC (-40 - 1500oF) at standard atmospheric pressure - Imperial and SI Units Humid Air and the Ideal Gas Law - Pressure, temperature and volume for an ideal or perfect gas like air with water vapor - or moist air Air Properties - Density, specific heat, thermal conductivity, expansion coefficient, kinematic viscosity and Prandtl's number - air temperature ranging -150 oC to 400 oC Density of Moist Humid Air - Density of dry air, water vapor or the mixture of air and water vapor - moist or humid air Air Solubility in Water - Amount of air that can be dissolved in water - decreases with temperature - increases with pressure Nitrogen - Specific Heat - Specific heat of Nitrogen Gas - N2 - at temperatures ranging 175 - 6000

 K Air - Molecular Mass - Dry air is a mixture of gases where the molecular weight can be calculated by adding the weight of each component Oxygen Gas - Specific Heat - Specific heat of Oxygen Gas - O2 - at temperatures ranging 175 - 6000 K

Question: The air we breathe is made up of 78.09% of what gas?
Answer: Nitrogen