A sample of gas has a volume of 8.00 L at 20.0 ° C and 700. torr. What will be its volume at STP?

Question

chmvijay · Answer

use the equation PV=n RT

chmvijay · Answer

P1V1 /T1 =P2V2/T2
can you solve now :)
for STP you take For STP, use 273K(T1), 760 torr(P1), V1=?
P2 =700 torr ,T2=20+273 =293 K ,V2=8L

anonymous · Answer

i have tried that equation a few times and still get teh wrong answer

chmvijay · Answer

what is the answer you are getting

chmvijay · Answer

LOL tell me quickly :)

anonymous · Answer

ok ..sorry, trying to finish a timed quiz..i will tell you

anonymous · Answer

so i do (700x8.00)/293.15=(760)v2/273.15

anonymous · Answer

I get 2.78 on right, multiply to cancel on right then multiply on left..i get...

anonymous · Answer

53.15 as v2

anonymous · Answer

that's not right

chmvijay · Answer

LOL u get 6.82 Litres

anonymous · Answer

how?

chmvijay · Answer

760 * V1 /273 =700 *8   /293 
        V1 =700*8*273   /    760*293
=6.86 L

anonymous · Answer

i'm looking for v1 then not v2?

chmvijay · Answer

yaa LOL P1 and V1 are at STP values then V1 value u are looking for :)

anonymous · Answer

how would i have known that the stp is your number 1 values instead of what was given in the question?

chmvijay · Answer

sorry that i didn't mentioned  it
 1 values are for STP i thought by putting those standard values u will understand but u didnt :)

anonymous · Answer

I worked it out...i got the answer but still a little confused... do you have time for one more?

chmvijay · Answer

what confusion ???

anonymous · Answer

this whole chapter is confusing!!

chmvijay · Answer

LOL :)

anonymous · Answer

can i ask you one more...how many moles are present in 10.0L of nitrogen gas at STP?

anonymous · Answer

I know it's easy but i'm definitely not remembering soemthing

chmvijay · Answer

22.4 litres of any gas = 1 mole
10 litres = 1*10  /22.4 =0.44 mole :)

anonymous · Answer

how am i canceling the 10.0L of NO?

anonymous · Answer

so i got as far as 10.0LNO(

chmvijay · Answer

iam not getting you ??

anonymous · Answer

ok..so i know this is dimensional analysis..we need to cancel liters

chmvijay · Answer

yaaaa :)

anonymous · Answer

|dw:1368380931292:dw|

anonymous · Answer

Questions marks are where i'm confused. I can't figure how to cancel the liters and get to moles

chmvijay · Answer

|dw:1368381006687:dw|

anonymous · Answer

ooooooohhhhh...ugh!! i'm such an idiot! THANK YOU!!

chmvijay · Answer

:)

anonymous · Answer

Final is tomorrow...i'm overwhelmed and barely understand this...

chmvijay · Answer

ok all the best :)

anonymous · Answer

yea..thanx