Unit 2 Gas laws question

[hutchooo]

I was wondering if anyone could help me with this question,

A syringe contains 90mL of gas measured at 1 atm pressure at 25 °C.
a) what volume would the gas occupy at 1 atm and 120 °C?
b) what volume would the gas occupy at 1 atm and -90 °C?

I think that you're meant to use Charles' law, but i'm unsure..

Thanks (:

[98.40_for_sure]

You're given:
V - 0.09L
P - 101.3kPa
T - 298K
R - 8.314
Use n=PV/RT to find n

Since the no. of mol does not change, you can use the equation V=nRT/P and find a) and b)

[hutchooo]

I tried redoing the question a few times, but I still don't understand. Do you think you could do the a) for me, so that i could follow the steps in it please?

[toshibaj]

Umm he pretty much said exactly how to do it...

using the info given,   n = PV/RT = 101.3 x 0.09 / (8.314 x (25+273) ) = 3.68 x 10^-3 mol

Then for part a) you use: V = nRT/P = 3.68 x 10^-3 x 8.314 x (120 + 273) / 101.3 = 0.119 L

[hutchooo]

Okay. I suppose i'll improve with practice, thanks heaps