Why is the average velocity of the particles greater in 1 mole of hydrogen gas at 25 (1 Viewer)

[bubb]

Why is the average velocity of the particles greater in 1 mole of hydrogen gas at 25 degrees C then 1 mole of water vapour at 25 degrees C?

 

[InteGrand]

Re: Why is the average velocity of the particles greater in 1 mole of hydrogen gas at

Why is the average velocity of the particles greater in 1 mole of hydrogen gas at 25 degrees C then 1 mole of water vapour at 25 degrees C?

Basically because hydrogen has a lower molar mass than water (H₂O). If you want a detailed explanation, check up the Maxwell-Boltzmann distribution, which is the probability distribution used to describe particle velocities; you will see from the equations that a larger molar mass leads to a lower mean and mode velocity.

http://en.wikipedia.org/wiki/Maxwell–Boltzmann_distribution#Distribution_function

 

[InteGrand]

Re: Why is the average velocity of the particles greater in 1 mole of hydrogen gas at

Actually, this section of the page is relevant for the mean and mode velocity expressions/calculations: http://en.wikipedia.org/wiki/Maxwell–Boltzmann_distribution#Typical_speeds

 

[QZP]

Re: Why is the average velocity of the particles greater in 1 mole of hydrogen gas at

Temperature correlates to the average kinetic energy (KE) of the particles.
KE = 1/2 mv^2 (from physics)
If m (mass) is lower, v (velocity) is higher for some temperature i.e. fixed KE