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Introduction:Air has molecules that are part of a constant motion with collisions due to kinetic energy of the atmosphere. The estimated rate at which the molecules collide is at 10 to the power of 10 collisions per molecule per second at 10 centigrade near sea level temperature. Using this study, we can further study the interactions of these particles based on three irrelevant properties: pressure, density, and temperature.Density: Density is the mass of the molecules of air per unit volume. The Mass has a unit of kg and volume in meters cubed. Some might assume that the kilograms are based on weight but according to newton’s laws, kilograms is mass and the mass multiplied by the gravitational acceleration constant gives us the weight. At sea level, the density of air is measured to be close to 1.2 kg per meter cubed. In fact, air density decreases based on the altitude from the ground on earth. Pressure:Pressure is simply a combined effect of push excreted by the molecular collision in its surroundings. It is defined as force per unit area. Fore is the product of mass and the acceleration and has a unit of newton. Area is united by meter squared. Pressure’s unit is Pascal. Most of the times, atmospheric pressure is measured in millibars where 1 millibar is 100 Pascals. The mean pressure at sea-level seems to be at 1013 mbar or close to a 100 kilo Pascals. The pressure is exerted in all directions and all sides on each and every object. A pressure of 1000 mbar results from the weight exerted by 10,000 kg of air overlying one square metre of surface by gravity. The huge pressure does not crush us because it is exactly balanced by outward pressure from the inside of our bodies.Temperature:Temperature is defined as a measurement of average speed of moving air molecules. In other branches of physics, it is measured on Kelvin scale which starts from 0 K. The temperature of a mass of air depends on the average velocity of the air molecules and their mass. Hence, temperature increases with air density. Boyle’s Law:Robert Boyle employed a J-shaped piece of glass tubing that was sealed on one end. A gar was trapped in the sealed end of the tube and varying amounts of mercury were added to the J-shaped tube to vary the pressure of the system. Boyle systematically varied the pressure and measured the volume of the gas. The measurements were performed using a fixed amount of gas and a constant temperature. In this way, Boyle was able to examine the pressure-volume relationship without complications from other factors such as changes in temperature or amount of gas. Boyle’s Law: P1V1=P2V2Charles’s LawJust as Boyle, Charles took care to keep all properties of gas constant except for temperature and volume. The equipment used by Charles was similar to that employed by Boyle. A quantity of gas was trapped in a J-shaped glass tube that was sealed at one end. This tube was immersed in a water bath; by changing the temperature of the water, he was able to change the temperature of the gas. The pressure was held constant by adjusting the height of mercury so that the two columns of mercury had equal height, and thus the pressure was always equal to the atmospheric pressure.V1/T1=V2/T2Ideal Gas Law:Combining these two laws, we can make the Ideal Gas law which is PV = nRT Were we can make the equation (PV/T)1=(PV/T)2 ................
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