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Re: [MW:27980] Re: Required Hydrotest pressure Drop calculation due to Temperature drop

By Materials & Welding

Segunda ley de Gay-Lussac



La segunda ley de Gay-Lussac dice:

  • Si el volumen se mantiene constante, el cociente entre presión y temperatura (Kelvin [1]) permanece constante:
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P / T = k

Esta ley fue enunciada en 1805 por el físico y químico francés Louis Joseph Gay-Lussac.

¿Por qué ocurre esto?

Al aumentar la temperatura las moléculas del gas se mueven más rápidamente y por tanto aumenta el número de choques contra las paredes por unidad de tiempo, es decir, aumenta la presión ya que el recipiente es de paredes fijas y su volumen no puede cambiar.

Gay-Lussac descubrió que, en cualquier momento del proceso, el cociente entre la presión y la temperatura tenía un valor constante.

Supongamos que tenemos un gas que se encuentra a una presión P1 y a una temperatura T1 al comienzo del experimento. Si variamos la temperatura hasta un nuevo valor T2, entonces la presión cambiará a P2, y se cumplirá:


P1 / T1 = P2 / T2, que es otra manera de expresar la segunda ley de Gay-Lussac.

Esta ley, al igual que la de Charles, está expresada en función de la temperatura absoluta. Es decir, las temperaturas han de expresarse en Kelvin.


El dom., 24 jun. 2018 a las 5:26, Ibrahim Kodssi (<ibrahimkodssi@gmail.com>) escribió:
Interesting equation. Any reference or analysis for this equation?

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