Question

We observe that 7 grams of a gaseous com-
pound occupies 2102 mL at 49C and 626 torr.
What is the molecular weight of the com-
pound?

Answer 1

Use PV = nRT and solve for n = number mols. Then n = grams/molar mass. You have n and grams, solve for molar mass.

Answer 2

I did 662(2.102)=n(62.37)(322) and got n=.069288. then I divided n by 7 and got 101.020 g/mol, but that is incorrect. I do not understand what i did wrong.

Answer 3

I wonder if you transposed your numbers for pressure. You have 626 in the problem but 662 in your work. If I run 626 torr through the calculations I get 0.065 something. Then 7/n = molar mass = appoximately 106. (I think you did 7/n but that isn't what you said you did.)