r1r2 = rate of diff of O2rate of diff of gas X = v1*t2v2 * t1
v1 --> Vol of of O2 Diff.
t1-->Time taken for O2 to diff.
v2--> Vol of of gas X Diff.
t2-->Time taken for O2 to diff.
There fore 500 * 85500*55 = √Mol. wt of gas XMol. wt of O2 --> ACc to greyham's law...
Now solve to get ans. 289/121 * 32 = 76.42 gm ... Is this the ans.?