Answer:0.124 mol- I think not completely positive on it
Explanation:6680⋅mm⋅Hg is not a realistic measurement of pressure....
I assume you mean 6680⋅mm⋅Hg/760⋅mm⋅Hg⋅atm^-1 = 8.79⋅atm.
And we use the Ideal Gas Equation:
n=PV/RT=8.79⋅atm×0.347⋅L/0.0821⋅L⋅atm⋅K−1⋅mol−1×300⋅K=0.124⋅mol