A gaseous sample weighing 0.896 g was found to occupy a volume of 524 mL at 730 mmHg and 28C. What is the molar mass of the gas?
I know I have to use M= mRT/PV
Theres an example in my book to set it up:
=0.896g x 62,400mL-mm Hg/mol-K x 301 K / 730 mmHg x 524 ml
My question is, where did that 62,400 mL-mm come from?
2006-11-09 06:37:34 · 3 answers · asked by megan6288 1 in Science & Mathematics ➔ Chemistry
"62,400mL-mm Hg/mol-K" is apparently the value of R you're using. I don't know, I don't normally work with mmHg. But all that--"mL-mm Hg/mol-K"--is the units for R. I know it looks like you're subtracting mm from mL, which wouldn't make sense, but the book means to multiply it. I would have written that "mL*mmHg/mol*K", or maybe "mL*mmHg*mol^-1*K^-1". Sorry for the confusion. I HATE poorly written textbooks (i.e. almost all textbooks).
2006-11-09 06:43:33 · answer #1 · answered by Amy F 5 · 0⤊ 0⤋
R in the equation is the ideal gas constant
it is standard in which you will use in all your problems
why that number is there? I can't explain it in words we both will understand
62,400mL-mm Hg/mol-K has to be used in this problem and other problems for R
some the equilvalent .0821 L-atm/mol-K could be used for R also
2006-11-09 14:57:33 · answer #2 · answered by cdixon 2 · 0⤊ 0⤋
it should be the value of R
R= PV / nT,, so the unit of R will be (mmHg.ml /mol.K)
2006-11-09 15:04:44 · answer #3 · answered by source_of_love_69 3 · 0⤊ 0⤋