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topdent1
07-16-2008, 12:42 PM
An ideal gas is contained in a one-liter vessel at 350 K. What additional information is sufficient to determine the pressure of the gas?
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifA. the molecular weight of the gas
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifB. the number of gas molecules
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifC. the molecular weight and the mass of the gas
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifD. B or C
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifE. A, B, or C

The problem doesn't state that it is at STP. In addition, 350K and 1L are not STP values. So..how can answer choice B (and C) be the correct answer? Wouldn't you need to be at STP for it to work?
slick90210
07-16-2008, 12:48 PM
An ideal gas is contained in a one-liter vessel at 350 K. What additional information is sufficient to determine the pressure of the gas?
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifA. the molecular weight of the gas
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifB. the number of gas molecules
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifC. the molecular weight and the mass of the gas
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifD. B or C
http://jasper.kaptest.com/apps/delivery/media/img_radio_o.gifhttp://jasper.kaptest.com/apps/delivery/media/img_radio_x.gifE. A, B, or C

The problem doesn't state that it is at STP. In addition, 350K and 1L are not STP values. So..how can answer choice B (and C) be the correct answer? Wouldn't you need to be at STP for it to work?

From my understanding if you wanted to put this question into PV=nRT
you would need the number of moles. For moles all you would need is the number of gas molecules, using Avogadro's number solve for n.