AP Chemistry HELPPPP!?

Question

Please Help:

On a mountain top, it is observed that water boils at 90*C, not at 100*C as at sea level. This phenomenon accurs because on the mountaintop the

A) Equilibrium water vapor pressure is higher due to the higher atmospheric pressure.
B) Equilibrium water vapor pressure lower due to the higher atmospheric pressure.
C) equilibrium water vapor pressure equals the atmospheric pressure at a lowere temperature
D) Water molecules have a higher average kinetic energy due to the lower atmospheric pressure
E) Water contains a greater concentration of dissolved gases

Answer 1

letter C

Answer 2

Atmospheric pressure is lower on the moutaintop, so A and B are out.

Average kinetic energy in the water molecules is due to the temperature, so D is out.

Dissolved gases have nothing to do with this, so E is out.

That leaves C. And C makes sense, because the water vapor pressure will equal the lowered atmospheric pressure at a lower temperature.

Answer 3

Substances boil when their vapor pressure = atmospheric pressure.

On top of the mountain the atmospheric pressure is lower so the water vapor pressure has to be raised to a lower number, thus requiring less energy.

(Scooter, I teach this to my 9th graders in Physical Science!
Read your book and get a good understanding of the theories).

Answer 4

C

because at higher altitudes, atmospheric pressure is lower than at sea level.

boiling occurs when the water vapour pressure = atmospheric pressure.

Answer 5

i took AP Chem and i thought i was pretty good at chem. but OMG its hard. really hard. take drawing if that was you really want ! follow your heart lol if your worried about getting into a pre-med program take BIO i guess...but just remember by the time u go through college (if ur still interested in med-a lot can happen in college) the med schools u apply for wont really be interested in what class you took in high school. and many colleges require u to score at least a 4 on the AP test to accept it as any college credit