Partial pressures

[md2be89]

I thought that partial pressure changes do not cause changes in other partial pressures because total pressure would compensate? Looking at number 19, hope the pics come out ok.
View attachment ImageUploadedBySDN Mobile1337397921.801083.jpgView attachment ImageUploadedBySDN Mobile1337398016.276445.jpg

---

Members don't see this ad.

 

[md2be89]

B is the correct answer. I posted it from my phone and just looked at my laptop and realized the awful quality. Sorry! Can someone explain why the partial pressure of O2 and N2 would decrease? Thanks!

 

[gettheleadout]

Can you post a closer picture of the answer explanation at the bottom of the page?

 

[zainsultan]

I think it's because the atmospheric pressure is always constant

 

[umdnjmed]

I think the total pressure will be constant. As the moles of water vapor increase, the denominator in the equation for mole fraction increases. Therefore the mole fractions of N2 and O2 are decreased. Since partial pressure = mole fraction x total pressure, the partial pressures of N2 and O2 must decrease.