Getting from PPM to Relative Humidity

[FourEyes88]

I have a chamber reading of 2.8 ppm O2 and 2.3 ppm moisture from a 1 ft³ sample space, 1 atm pressure filled with Nitrogen at 92.8°. Now I'm trying to get a relative humidity %, I'm approaching this by trying to first figure out the dew point and work forwards from there. The issue I'm having is I'm hung up on how to relate the O2 and moisture ppm to the dew point... any recommendations?

Thanks!

 

[Compositepro]

O2 is irrelevant. 2.3 ppm is the absolute humidity. Convert that to a partial pressure. Divide that by the vapor pressure of water at your temperature.

 

[willard3]

Sounds very much like a homework problem