[Sona]

Calculate the thermal de-broglie wavelength of H atom at 3000K confined to move in a box of Volume 0.25m³

How this problem can be solved?

λ=h/mv

From temp I can calculate v_rms, and putting the values in the equation will I be able to get the value?
How the volume part should be used? If PIAB is applied to calculate the energy then also as individual lenghts arenot given, it is becoming complicated.

How it should be done? Please help

[Enthalpy]

My guess is that a box would determine the wavelength if it were much smaller (but is it still called De Broglie then?) Just compute a wavelength without any confinement and compare with the box.

Mind that the thermal energy has components over x, y and z. Compare with the definition of the De Broglie's wavelength.

For PIAB, I've found so far:
The President's Intelligence Advisory Board
The Piping Industry Apprenticeship Board
and a few companies.
Maybe you could tell me in plain English?

[Corribus]

PIAB = particle in a box

[Enthalpy]

Aaaaaaaaah yes! Thanks!

0.25m³: check what dimension would make a change to the wavelength of the atom as compared to vacuum, and then decide if a box with that volume and thickness can exist.