Gas laws - Wikipedia
The ideal gas law is the equation of state of a hypothetical ideal gas. Ideal gases are essentially point masses moving in constant, random, straight-line Standard condition of temperature and pressure is known as STP. The ideal gas law is the equation of state of an ideal gas. It relates Gases can be compressed because most of the volume of a gas is empty space. If temperature and amount of gas is fixed then pressure is inversely proportional to volume. The pressure, volume, and temperature of most gases can be described with simple mathematical relationships that are summarized in one ideal gas law.
However, there is no real gas that can perfectly fits this behavior, so the Ideal Gas Law only approximates the behavior of gases.
This approximation is very good at high temperatures and low pressures. At high temperature the molecules have high kinetic energy, so intermolecular attractions are minimized. At low pressure the gas occupies more volume, making the size of the individual molecules negligible. These two factors make the gas behave ideally.
Gas Laws: Overview - Chemistry LibreTexts
At low temperature or high pressure, the size of the individual molecules and intermolecular attractions becomes significant, and the ideal gas approximation becomes inaccurate. Eudiometers and Water Vapor[ edit ] Helpful Hint! In calculations for a gas above a liquid, the vapor pressure of the liquid must be considered.
A eudiometer is a device that measures the downward displacement of a gas.
The apparatus for this procedure involves an inverted container or jar filled with water and submerged in a water basin. The lid of the jar has an opening for a tube through which the gas to be collected can pass. For laboratory work the atmosphere is very large. A more convient unit is the torr.
A torr is the same unit as the mmHg millimeter of mercury. It is the pressure that is needed to raise a tube of mercury 1 millimeter.
- Ideal Gas Law: Volume & Temperature Relationship
- General Chemistry/Gas Laws
The Pressure-Volume Law Boyle's law or the pressure-volume law states that the volume of a given amount of gas held at constant temperature varies inversely with the applied pressure when the temperature and mass are constant. Another way to describing it is saying that their products are constant. When volume goes up, pressure goes down.
From the equation above, this can be derived: This equation states that the product of the initial volume and pressure is equal to the product of the volume and pressure after a change in one of them under constant temperature. For example, if the initial volume was mL at a pressure of torr, when the volume is compressed to mL, what is the pressure?
Gas Laws: Overview
Plug in the values: The Temperature-Volume Law This law states that the volume of a given amount of gas held at constant pressure is directly proportional to the Kelvin temperature. V Same as before, a constant can be put in: Also same as before, initial and final volumes and temperatures under constant pressure can be calculated. The Pressure Temperature Law This law states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature.
P Same as before, a constant can be put in: The Volume Amount Law Amedeo Avogadro Gives the relationship between volume and amount when pressure and temperature are held constant.
General Chemistry/Gas Laws - Wikibooks, open books for an open world
Remember amount is measured in moles. Also, since volume is one of the variables, that means the container holding the gas is flexible in some way and can expand or contract.
If the amount of gas in a container is increased, the volume increases.