So recently I was thinking gases (at least colourless ones) are more transparent in their gaseous state than liquid state.
And as we talk of continuity in liquid and gaseous state (fluids) is it possible that gases become more and more opaque as their number density (number of gas molecules per unit volume) increases (by cooling, compression, etc) increases.
Consider a ideally cubical transparent container with a gas in it and compress it continuously. Assume a monochromatic light source behind the container giving out light with constant intensity with all light rays parallel to each other. Would intensity of transmitted light decrease as number density increases?
It would seem true intuitively to me I guess but I cannot figure out why?
So my question:
Is it possible to relate the intensity of transmitted light with number density of gas (Mathematically)?
Please provide validation too for your formula or reasoning.