Name: gas mixtures and their partial pressures
Uploaded: 2023-09-18T17:11:17.000Z
Duration: 1 min 11 s
Channel: JoVE

Pensemos en un gas dentro de un contenedor. La presión ejercida por el gas es la suma de las fuerzas ejercidas debido a las colisiones moleculares entre sus moléculas y la superficie circundante.
Un gas con muchas moléculas ejerce una presión más alta que un gas con un número menor de moléculas en el mismo recipiente. Por lo tanto, la presión del componente individual se denomina presión parcial.
Considere una mezcla de gases ideales en un recipiente en equilibrio térmico. La presión total dentro del recipiente es igual a la suma de las presiones parciales de sus componentes. Esta observación se conoce como la ley de Dalton de las presiones parciales.
Recordando la ecuación del gas ideal y sustituyendo las presiones parciales de los gases individuales, se puede determinar la presión total.
La presión parcial de un vapor que está en equilibrio con la fase líquida de la misma sustancia se denomina presión de vapor.
La relación entre la presión parcial del vapor de agua y la presión de vapor del agua a una temperatura se conoce como humedad relativa.

<ol>
	<li>OpenStax. (2019). Física Universitaria Vol. 2. [Versión web], págs. 37 - 38. Obtenido de <a href="https://openstax.org/books/university-physics-volume-2/pages/2-2-pressure-temperature-and-rms-speed">https://openstax.org/books/university-physics-volume-2/pages/2-2-pressure-temperature-and-rms-speed</a></li>
</ol>

ley de las presiones parciales de dalton

Dalton's Law of Partial Pressure

La presión parcial de un gas es una medida de la actividad termodinámica de las moléculas del gas. La presión que un gas crearía si ocupara el volumen total disponible se llama presión parcial del gas. Si dos o más gases se mezclan en un recipiente, las moléculas se mueven al azar y chocan entre sí, lo que hace que alcancen el equilibrio térmico. Cuando los gases tienen la misma temperatura, sus moléculas tienen la misma energía cinética promedio. Por lo tanto, cada gas sigue la ley de los gases ideales por separado y ejerce la misma presión sobre las paredes del recipiente individualmente. Por lo tanto, en una mezcla de gases, la presión total en el recipiente es la suma de las presiones parciales de los gases componentes, asumiendo un comportamiento de gas ideal y sin reacciones químicas entre los componentes. Esta ley se conoce como la ley de las presiones parciales de Dalton. La teoría fue establecida por el científico inglés John Dalton (1766-1844). La ley de Dalton es consistente con el hecho de que las presiones se suman, de acuerdo con el principio de Pascal. En una mezcla de gases ideales en equilibrio térmico, el número de moléculas de cada gas es proporcional a su presión parcial. Otra aplicación importante de la presión parcial es la presión de vapor, que es la presión parcial de un vapor en equilibrio con la fase líquida de la misma sustancia. A cualquier temperatura, la presión parcial del agua en el aire no puede exceder la presión de vapor del agua a esa temperatura, ya que cuando la presión parcial alcanza la presión de vapor, el agua se condensa fuera del aire. El rocío es un ejemplo de esta condensación. La temperatura a la que ocurre la condensación para una muestra de aire se llama punto de rocío. Se puede medir fácilmente enfriando lentamente una bola de metal; el punto de rocío es la temperatura en la que aparece la condensación por primera vez en la bola.

Ley de las presiones parciales de Dalton

La presión parcial de un gas es una medida de la actividad termodinámica de las moléculas del gas. La presión que crearía un gas si ocupara ...

Education

Educación

JoVE Core

Physics

Física

Unit 1

Unidad 1

The Kinetic Theory of Gases

La teoría cinética de los gases

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

gas mixtures and their partial pressures

Gas mixtures have a total pressure that comes from the partial pressures of each gas. A partial pressure is the pressure one gas would make if it filled the whole container by itself. This idea helps explain how gases behave when they are mixed together.

When two or more gases share a container, their molecules move randomly and collide with one another. If the gases are at the same temperature, they reach thermal equilibrium. Their molecules then have the same average kinetic energy. In that case, each gas follows the ideal gas law separately and pushes on the walls of the container on its own.

The total pressure in the container is the sum of the partial pressures of the component gases. This result is called Dalton's law of partial pressures. It applies when the gases behave like ideal gases and do not react chemically with one another. The law was developed by the English scientist John Dalton, who lived from 1766 to 1844. It also agrees with Pascal's principle, which says that pressures add up.

Partial pressure also helps describe vapor pressure. Vapor pressure is the partial pressure of a vapor when it is in equilibrium with the liquid form of the same substance. In air, the partial pressure of water cannot rise above the vapor pressure of water at that temperature. If it reaches that value, water condenses out of the air. Dew is one common example of this process.

The temperature where condensation begins in a sample of air is called the dew point. One simple way to measure it is to cool a metal ball slowly. The dew point is the temperature at which condensation first appears on the ball.

Gas Mixtures and Their Partial Pressures

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Gas Mixtures and Their Partial Pressures | JoVE K12

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JoVE Core Física presenta la teoría y la aplicación de conceptos físicos fundamentales, como la cinemática, dinámica, mecánica de fluidos, estática, ondas y acústica, mediante animaciones audiovisuales concisas y fáciles de entender. Además, los vídeos de científicos en acción muestran la aplicación de los conceptos relacionados en experimentos de investigación clásicos y originales, realizados en laboratorios de todo el mundo.

Gas Mixtures and Their Partial Pressures

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