I need to a way to see how temp. effects the solubility of a gas, using a hot pot beaker and 50 ml of seltzer water
thanks

As temperature increases, pressure increases. Go from there lol. I forget solubility rules.

when CO2 goes into water, it forms H2CO3.

CO2 + H2O <--> H2CO3
i use a <--> because the reaction can go back or forth

http://en.wikipedia.org/wiki/Le_Chatelier%27s_principle

just get 3 bottles of coke or something, open them. place one in ice water, one at room temperature, one in a pot of hot water. keep one with a lid on as a control. be sure to keep as many of the other variables the same

after about 10 minutes, weigh them all, including the lid

the one in higher temperatures should be lighter as the CO2 escapes into the air

edit: on second thought, dont use the bottle with a lid on it. the reason is because the pressure is different. the one at room temperature is the control.

therefore, the only independent variable is temperature, and the depended variable is the mass.
to calculate the amount of CO2 lost, get an unopened bottle and weight it. weigh your samples. subtract the mass of the unopened bottle with the mass of the samples, and thats the amount of CO2 lost.

use
moles = mass/molar mass
to find the number of moles of CO2 lost

thats what i was thinking, but it would be fiddly. Condensation on the cold bottles will cause problems, and weighing water is a little annoying if your impatient like me.

measuring the pressure in the headspace of different temp bottles will give you easily reproducable results, but isn't technically correct as the water itself will have different vapour pressures at different temperatures. This may be small enough to correct, and is definitely able to be adjusted for in the results using standard values.

I did the wieghing and it worked out
actually got some solid results
Thanks!

if it is anything like the labs we had back in school, you had to find sources of non human error:

-evaporation of water from the hot sample
-condensation of water on the cool bottles.
-possible slighly different batch, and composition for each bottle

etc

You need to look up and use Henry's Law for those types of problems. It's usually some form of e^p = e^kc. p is the partial pressure, c the concentration, and k is a constant that has tempurature dependance built into it. I think you use the Vant Hoff equation to pull temp out of there. You should be able to figure it out.