Sorry still confused. Here's the problem:

0.249g of a diatomic element occupies a volume of 125mL at 120 degrees Celsius and 2.00 atm. This element IS?

I used PV/RT =n so:
2.00 atm (.125L)/0.0821L*atm/mol*K (393K) = 11.96 then 0.249/11.96 =20.1 which is Neon. It isn't diatomic. PLEASE HELP ME. I'm losing my mind.

1 answer

You must not be punching the calculator in the right places. I get n = 0.00775 which is a far cry from 11.96.
0.249/0.0075 = about 32.