What is the Difference Between Combined Gas Law and Ideal Gas Law?

The Combined Gas Law and Ideal Gas Law are both used to describe the behavior of gases under different conditions. However, there are some differences between the two:

Variables: The Combined Gas Law relates the variables pressure, temperature, and volume, while the Ideal Gas Law includes these three variables plus the number of moles of gas.
n: The Combined Gas Law does not include the number of moles (n) as a variable, while the Ideal Gas Law does.
Purpose: The Combined Gas Law is used to determine how changes in pressure, volume, or temperature can be used to calculate the conditions of the resulting system when the number of moles of gas remains constant. The Ideal Gas Law, on the other hand, allows you to make predictions when the amount of gas is varied.
Equations: The Combined Gas Law can be expressed as $$P1V1T1 = P2V2T2$$, while the Ideal Gas Law is expressed as $$PV = nRT$$, where P represents pressure, V represents volume, T represents temperature in Kelvin, and R represents the ideal gas constant.

In summary, the Combined Gas Law is a restructuring of the Ideal Gas Law that focuses on changes in pressure, volume, or temperature when the number of moles of gas remains constant, while the Ideal Gas Law includes the number of moles of gas as a variable and allows for predictions when the amount of gas is varied.

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What is the Difference Between Combined Gas Law and Ideal Gas Law?

Comparative Table: Combined Gas Law vs Ideal Gas Law

The Combined Gas Law and Ideal Gas Law are both used to describe the behavior of gases under different conditions. However, there are some differences between the two:

Combined Gas Law	Ideal Gas Law
Combined Gas Law is a collection of three gas laws: Boyle's Law, Charles' Law, and Gay-Lussac's Law.	Ideal Gas Law is an individual gas law that combines Boyle's Law, Charles' Law, and Avogadro's Law.
The Combined Gas Law states that the ratio of the product of pressure and volume and the absolute temperature of a gas remains constant (PV/T = k).	The Ideal Gas Law states that the product of pressure (P) and volume (V) of an ideal gas is directly proportional to the absolute temperature (T) and inversely proportional to the number of moles (n).
The Combined Gas Law is used when the values of any three of the four parameters (P, V, T, n) are known, and the fourth needs to be calculated.	The Ideal Gas Law is used for ideal gases and real gases under specific conditions, such as when the temperature and pressure are not too high.

In summary, the Combined Gas Law is a combination of three individual gas laws, while the Ideal Gas Law is an individual law that incorporates multiple gas laws. The Combined Gas Law is used when any three parameters of a gas are known, and the fourth needs to be calculated, whereas the Ideal Gas Law is used for ideal and real gases under specific conditions.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.