Physics/Chem Gas, Pressure, Volume, Temperature Question

AI Thread Summary
The discussion revolves around a physics problem involving a balloon rising from a deep lake, where the temperature is consistently 4°C. Participants highlight the use of the Combined Gas Law (P1V1/T1 = P2V2/T2) to determine the initial pressure at depth and the temperature of the air above the lake. There is a consensus that additional values are needed to solve the problem, and the importance of assuming constant water density for calculations is emphasized. A corrected link to a diagram is provided to aid in visualizing the scenario. The discussion concludes with a focus on gathering the necessary information to apply the gas law effectively.
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Homework Statement


A balloon is released from the bottom of a deep lake where the temperature is always 4 degC and rises to the top, where the pressure is standard atmospheric pressure. Assume that the balloon rises slowly enough that the temperature of the gas inside adjusts to its surroundings. Determine the pressure at the initial depth and the temperature of the air above the lake.

Diagram is here:
http://iwp2.ncssm.edu/pps/webInterface.php/Users/winters@ncssm.edu/gas-laws-bubble-01b.iwp...
Sorry part of it got cut off

Homework Equations


P1V1/T1 = P2V2/T2

The Attempt at a Solution


I can't seem to start this because I am missing two of the values in the Combined Gas Law, so I can't solve for one or the other. Any suggestions? Thanks in advance
 
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I think you are missing some info, and the link to the diagram is incorrect.
 
I reposted the link. The applet also shows the depth in meters if that helps.
 
So you have the initial and final volume of the balloon as well.
You are probably also supposed to assume that the water density is constant so you can work out the initial pressure. (Hint lake=fresh water)
 
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