The definition of ideal Gas

The definition of ideal Gas

Gas is one of the three States of matter and although this form is an integral part of the study of chemistry, this chapter mainly discusses only the relationship between the volume, temperature and pressure in both the gas and ideal gas is real, and the molecular kinetic theory of gases, and not directly chemistry. The main discussion was mainly about the change of physics, and chemical reactions are not discussion. However, the physical properties of a gas depend on its gaseous molecular structure and chemical properties of gas also depends on its structure. Behavior of the gas exists as a single molecule is a good example of relying on the microscopic structure of macroscopic properties.

a. the nature of gases

The properties of gases can be dirangkumkan as follows.

Gas is transparent.

Gas is distributed evenly in any form its spatial spaces.

Gas in the space will give pressure to the walls.

The Volume of gas is equal to the volume of their vessels. If the gas does not undertakes, gas volume will be an infinite magnitude, and the pressure is going to be infinitely small.

Gases diffuse into all directions no matter the pressure out there or not.

When two or more mixed gases, the gases would be distributed evenly.

Gas can be suppressed with the outside pressure. When the outside pressure is reduced, the gas expands.

When heated, gases expand when cooled down will be mengkerut.

From various properties above, the most important thing is the pressure of the gas. Suppose a liquid filled containers. When a liquid is cooled down and the volume of liquid is reduced, it will not satisfy the container again. However, the gas will always fulfil space no matter regardless of the temperature. That will be changed is the emphasis.

Tools used to measure gas pressure is a manometer. The prototype of the atmospheric pressure gauge, barometer, created by Torricelli.

Pressure is defined as force per unit area, so pressure = force/area.

In SI, the unit of force is the Newton (N), unit area m2, and the unit of pressure is the Pascal (Pa). 1 atm is approximately equal to the pressure of 1013 hPa.

1 atm = 1,01325 x 105 Pa = 1013,25 hPa

However, in units of non-SI units, Torr, roughly 1/760 of 1 atm, often used to measure the change of pressure in chemical reactions (www.chem-is-try.org)

b. Volume and pressure

The fact that the volume of a gas is changed when the pressure change has been observed since the 17th century by the French philosopher and Torricelli/saintis Blase Pascal (1623-1662). Boyle observed that by wearing the pressure with a certain volume of mercury, the volume of gas trapped in a tube closed at delas one end, would be reduced. In this experiment, the volume of gas measured at a pressure greater than 1 atm.

Boyle makes vacuum pumps use engineering tercangih is the time, and he observed that gas at pressures below 1 atm will expand. After he did a lot of experiments, Boyle suggested equations (6.1) to describe the relationship between pressure and volume V P of the gas. This relationship is known as Boyle's law.

PV = k (a constant) (6.1)

Graphical appearance of Boyle's experiments can be done in two ways. When P is plotted as ordinat and V as the absis, obtained a Hyperbola

c. Volume and temperature

After more than a century the discovery of Boyle's scientist got interested in the relationship between the volume and temperature of the gas. Perhaps because of thermal balloon became the topic of conversation in kotakota that time. French chemist Jacques Alexandre César Charles (1746-1823), a navigator's famous balloons at that time, to recognize that, at fixed pressure, volume of gas will increase when the temperature is raised. This relationship is called Charles's law, even though the data is not quantitative. Gay-Lussac was the one who then memplotkan the volume of gas against temperature and get a straight line (Figure 6.2). For this reason Charles's law is often called Gay-Lussac's law. Both Charles's law and law of Gay-Lussac roughly followed by all gas during condensation does not occur.