Anzeige
Anzeige
Anzeige
Nächste SlideShare
Boyles Law
1 von 14
Anzeige

### Application of gases

1. Applications of Gas Laws GAS LAWS One of the most amazing things about gases is that, despite wide differences in chemical properties, all the gases more or less obey the gas laws. The gas laws deal with how gases behave with respect to pressure, volume, temperature, and amount.
2. BOYLE'S LAW The mathematic equation is equally as simple: PV=K where P=Pressure, V=Volume and K is simply a constant. This has become a basic principle in chemistry now called Boyle's law and is included as a special case into the more general ideal gas law Robert Boyle (1627-1691). In 1662, Robert Boyle discovered that when held at a constant temperature, the volume and pressure of a gas are inversely proportionate. Put simply, when the volume goes up, pressure drops, and vice versa.
3. Boyle’s Law Examples: Soda Can Typically we will take a bottle of soda, slowly turning the cap allowing the air to gradually escape before completely removing the lid. We do this because we've learned over time that popping it open too fast causes it to fizz up and spill all over you and everything around you. Carbonation is exactly as it sounds. Water is pumped full of carbon dioxide, causing it to bubble up as the CO2 makes its escape. Throw some syrup in the mix, and you have soda pop. When a soda bottle is filled, it is also pressurized. Much like the aerosol can, mentioned earlier, when you slowly open the cap, the gas is suddenly able to increase its volume in order to decrease the pressure. Since the soda itself is carbonized, the CO2 gasses decide they want to escape as well, and you have your fizz.
4. All is fine and dandy, until you shake the bottle up. Shaking up the bottle causes that neat pocket of carbon dioxide gas in the top to mix in with the soda. Now pop the cap off. Suddenly all of these excess gas bubbles within the soda want to expand and escape their high pressure environment as well. Rather than being able to expand and shoot out of that neat pocket of air with a pffffffft, they expand while they're still in the soda. As it tries to muscle its way out, it pushes the soda along with. Pressure in the bottle goes down, volume of the gas goes up, and you have yourself a mess to clean up. Spray Paint While there are a couple different types of aerosol cans, one being a little more elaborate than the other, they both operate off of the same basic principle: Boyle's law. We'll examine the more elaborate of the two, since it's far more popular.
5. We know that before you spray a can of paint you are suppose to shake it up for a while, listening as a ball bearing rattles around inside. There are 2 substances inside the can, one being your product, paint for example, the other being a gas that can be pressurized so much, that it retains a liquid state even when it is heated past its boiling point. This liquefied gas will be a substance that has a boiling point far below room temperature. The can is sealed, preventing this gas from boiling and turning into a gaseous state. That is, until you push down the nozzle. The moment the nozzle goes down, and the seal is released, there is now an escape route. The propellant instantly boils and expands into a gas and pushes down on the product trying to escape the high pressure, and expand it's volume the atmosphere where there is less pressure. This forces the product to shoot out from the nozzle, and you have a coat of paint.
6. CHARLES’S LAW What's interesting is that the person who published it, Joseph Gay-Lussac, insisted on crediting it to Jacques Charles' unpublished work of 20 years earlier. Charles' law is seen in action in many everyday examples. Here are some of them. Jacques Charles (1746 - 1823). The foundation of basic physics and chemistry are a few simple but extremely important laws. Charles' law states that, keeping everything else constant, there is a direct relationship between the volume of a gas and its temperature as measured in degrees Kelvin. Charles' law was first published in 1801.
7. Charles’s Law Examples: Helium Balloon on a Cold Day If you have bought a helium balloon for your child, you may have noticed this phenomenon. If it's cold outside, your child's face may fall when she notices that the helium balloon has crumpled. All isn't lost, of course, because once you enter your warm home, the balloon returns to its original shape. This is because, according to Charles' law, a gas takes up more space when it is warm.
8. The Dented Ping Pong Ball If you are into ping-pong, also called table tennis, a dented ping pong ball is something you have probably encountered. Rather than discard it, you can restore it by placing it into a saucepan half filled with water. Apply gentle heat to the saucepan, stirring constantly. If the ball is not cracked by the dent, the air inside will expand as it heats, pushing out the dent and restoring the ball to its original shape.
9. GAY-LUSSAC’S LAW Gay-Lussac's Law states that the pressure of a fixed amount of gas at fixed volume is directly proportional to its temperature in Kelvin. Simplified, this means that if you increase the temperature of a gas, the pressure rises proportionally. Pressure and temperature will both increase or decrease simultaneously as long as the volume is held constant. Joseph Gay-Lussac (1778-1850). Gay- Lussac’s Law is an ideal gas law where at constant volume, the pressure of an ideal gas is directly proportional to its absolute temperature. In other words,
10. Gay-Lussac’s Law Examples: Firing a bullet. When gunpowder burns, it creates a large amount of superheated gas. The high pressure of the hot gas behind the bullet forces it out of the barrel of the gun. A burning automobile tire. The heat from the burning rubber will cause the air pressure in the tire to increase. This can cause the weakened tire wall to explode.
11. Avogadro’s Law The carbon dioxide forms bubbles, and, as the yeast continues to leaven the dough, the increase in the number of particles of carbon dioxide increase the volume of the bubbles, thereby puffing up the dough. Amedeo Avogadro (1776-1856). Avogadro's Law, along with other gas laws, explains why bread and other baked goods rise. Yeast or other leavening agents in the dough break down the long carbohydrates from the flour or sugar and convert them into carbon dioxide gas and ethanol.
12. Avogadro's Law Explainations Projectile Projectiles, like cannons and guns; the rapid reaction of the gunpowder very suddenly creates a large amount of gas particles--mostly carbon dioxide and nitrogen gases--which increase the volume of the space behind the cannon or bullet until the projectile has enough speed to leave the barrel.
13. Balloon inflation A balloon inflates because of Avogadro's Law; the person blowing into the balloon is inputing a lot of gas particles, so the balloon increases in volume. We breathe because of Avogadro's Law, among others; the lungs expand, so more gas particles can enter the lungs from the outside air (inhaling). Then the lungs contract, so the waste gas particles are expelled (exhaling).
14. REFERENCES  "Boyle's Law Examples in Real Life."HubPages. HubPages, n.d. Web. 7 Oct. 2014. <http://hubpages.com/hub/Examples-of-Boyles-Law#>.  "Charles' Law Examples in Everyday Life." Answers.com. N.p., n.d. Web. 7 Oct. 2014. <http://chem.answers.com/chemistry-basics/charles-law- examples-in-everyday-life>.  "What is a real life application that demonstrates Gay-Lussac's gas law? | Socratic." Socratic.org. N.p., n.d. Web. 7 Oct. 2014. <http://socratic.org/questions/what-is-a-real-life-application-that- demonstrates-gay-lussac-s-gas-law>.  "ChemTeacher." ChemTeacher. N.p., n.d. Web. 6 Oct. 2014. <http://chemteacher.chemeddl.org/services/chemteacher/index.php?o ption=com_content&view=article&id=9>.  “Gas Laws”. Chemistry.bd.psu.edu. Web. 14 Oc 2014 <http://chemistry.bd.psu.edu/jircitano/gases.html>
Anzeige