Answer is: NaNO₃.
n(Na) = 1,18mol.
n(N) = 1,18mol.
n(O) = 3,53mol.
n(Na) : n(N) : n(O) = 1,18mol : 1,18mol : 3,53mol / ÷1,18
n(Na) : n(N) : n(O) = 1 : 1 : 3.
Empirical formula is NaNO₃ (sodium-nitrate).
Empirical formula of compound is the simplest ratio of atoms present in a compound.