Somebody please explain this to me..

[busdent]

---

Members do not see this ad.

AT 760 torr, solution X boils at 100.26 C and solution Y boils at 101.04 C. If both solutions contain the same non-volative solute, which of the following it a correct conclusion?

A. The freezing point of Solution X is lower than that of Solution Y.
B. Solution Y is saturated
C. The vapor pressure of solution X is higher than that of Solution Y at 25 C.
D. Solution X is hypertonic to Solution Y.
E. The vapor pressure of solution X at boiling point is greater than the vapor pressure of solution Y at boiling.

The answer Kaplan shows is C and I don't understand it at all.

Thanks

 

[NilamPatel]

vapor pressure is the pressure of a gas as equilibrium, if the pressure at eq is high then it will WANT to be a gas and boil more quickly aka at a lower boiling point.


compared to solution Y solution X wants to be a gas thats why it boils more quickly or has a higher vap pressure or lower bp.

synonymous:
higher vap pressure = lower boiling point
low vap pressure = higher boiling point

 

[Manyak222]

AT 760 torr, solution X boils at 100.26 C and solution Y boils at 101.04 C. If both solutions contain the same non-volative solute, which of the following it a correct conclusion?

A. The freezing point of Solution X is lower than that of Solution Y.
B. Solution Y is saturated
C. The vapor pressure of solution X is higher than that of Solution Y at 25 C.
D. Solution X is hypertonic to Solution Y.
E. The vapor pressure of solution X at boiling point is greater than the vapor pressure of solution Y at boiling.

The answer Kaplan shows is C and I don't understand it at all.

Thanks

I had this question and got it right by deduction. A has no merit, as freezing points can't be determined from bp's. B also cant be figured out with info given. D is also something you couldnt know given a BP. As far as E, When they are both exactly at boiling point, their Vapor pressure equals the atmospheric pressure, so assuming the exp is done at the same place, the vapor pressures are equal. That leaves C.
lets assume that they are both equal with regards to temp. At 100.26, x is at atmospheric pressure. At 100.26, Y is less than that and wont be at Atm pressure until it gets to 101.04. thus the vp of x is higher at that temp.

Hope this helps

 

[busdent]

thanks so much for the feedback