posted by Nikki on .
A 0.08425 g sample of gas occupies 10.0-mL at 292.5 K and 1.10 atm. Upon further analysis, the compound is found to be 13.068% C and 86.932% Br. What is the molecular formula of the compound?
Identify the geometry around each carbon atom. a)trigonal pyramidal b)bent c)tetrahedral d)linear e)trigonal planar Is the compound polar or nonpolar?
Use PV = nRT to solve for n = number of mols. Then n = grams/molar mass. You know grams and n, solve for molar mass.
Take 100 g sample which gives
13.068 g C
86.932 g Br.
Convert grams to mols
mols C = 13.068/atomic mass C.
mols Br = 86.932/atomic mass Br.
Find the ratio of C to Br with the smaller value being 1.00. The easy to do this is to divide the smaller value by itself; divide the other number by the same small number to find empirical formula which will be CxBry.
empirical mass x z = molar mass(from above)
Solve for x which becomes
(empirical formula)x = molecular formula.
Post your work if you get stuck.