Question

(a) An ideal gas occupies a volume of 1.6-cm3 at 20°C and atmospheric pressure. Determine the number of molecules of gas in the container.


(b) If the pressure of the 1.6-cm3 volume is reduced to 1.6 10-11 Pa (an extremely good vacuum) while the temperature remains constant, how many moles of gas remain in the container?



ok, i took the equation PV = nRT
where
P = atmospheric pressure which i believe is 1.5 x 10 ^5
V = 1.6 x 10 ^-6 m^3
R = 8.31
and T = 293

and then i mulitiplied the answer i got times 6.02 x 23 to convert to molecules....but it's not right.

Answer 1

I would memorize atmospheric pressure as 101.3kPa

Answer 2

so i did that and I got 4.0 X 10 ^16


and it's still wrong...am I just missing a conversion somewhere or something like that?

Answer 3

never mind, i got it. thanks so much!