Hi everyone. I have figured out most of this question but the last part is really getting me. I haven't been in a chemistry class for awhile so I am a little rusty. If someone could tell me what direction to think in that would be great

A sample of 2.14 g of a gaseous organofluorine compound occupies a volume of 2.00 L at 25.5 C and 30.2 kPa. What is the molar mass of this compound and what is it's formula?

So using PV=nRT

n= (0.298atm)(2.00L)/(0.08205 L atm K-1 mol-1)(298.65 K)

= 0.0243 mol

Then using M=m/n

M = 2.14g/0.0243 mol

= 87.9 g/mol

So I determined the molar mass but now how do I get the formula?

Thanks