# Problem: 1.560 x 10-4 mol of an unidentified gaseous substance effuses through a tiny hole in 98.8 s.Under identical conditions, 1.749 x 10-4 mol of argon gas takes 84.9 s to effuse. What is the molar mass of the unidentified substance (in g/mol)? The percentage C by mass in the above unidentified substance is 53.0%. It may also contain H and/or O, but no other element. What is the molecular formula of the substance? In typing this formula use the convention of C first, H second and O last. For example, C6H8O2 would be C6H802.) Under identical conditions, how many moles of acetylene (C2H2) gas would effuse in 86.5 s?

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###### Problem Details

1.560 x 10-4 mol of an unidentified gaseous substance effuses through a tiny hole in 98.8 s.

Under identical conditions, 1.749 x 10-4 mol of argon gas takes 84.9 s to effuse.

What is the molar mass of the unidentified substance (in g/mol)?

The percentage C by mass in the above unidentified substance is 53.0%. It may also contain H and/or O, but no other element.

What is the molecular formula of the substance?

In typing this formula use the convention of C first, H second and O last. For example, C6H8O2 would be C6H802.)

Under identical conditions, how many moles of acetylene (C2H2) gas would effuse in 86.5 s?