Question

Nitric oxide (NO) occurs in the atmosphere naturally at a concentration of 0.1ppb. determine whether or not this concentration represents e equilibrum with respect to H2o,O2 and NH3(amonia), all in the gasous phase. a)Covert the concentration of NO to its partial pressure, assuming an atmospheric pressure of 1 bar. b)calculate the partial pressure of NH3 if the system uis controlled by chemical equilibrum.

Answer 1

NO atmosphere = 0.1 ppb

Central to conversion between different gas concentrations is

PV = nRT

0.1 ppb of a gas means:

- there are 0.1 gas molecules for every 1 billion molecules of air

- there are 0.1 moles of gas for every billion moles of gas

- 0.1 x 10^‐12 atm partial pressure of gas for 1 atm total air pressure

I made a research and i found in different sides this concentrations for the other gasses mentioned above in the atmosphere:

water 10–50,000ppm O₂ 209,460ppm ammonia  0.3 to 6 ppb

You can see that the difference between ppm and ppb is huge, is about a million parts.

So if you compare the quantity of water and O₂ the amount of NO and NH₃ are negligible.

a) we have this: 0.1 ppb means:

0.1 x 10^‐12 atm partial pressure of gas for 1 atm total air pressure

then 1 bar = 0.9869 atm. then we do the relation to find the partial pressure.

(1atmtotal air ) (0.1x10^-12atm NO) /0.9869 atm total air = 1.013x10^-13 atm is the partial pressure of NO.

b) really i dond kite understand the question. I think there are some data missing. If you have some more data please let me now.

Hope i could help you!