So gold is Au is 196.6 g and that is for 1 mol of gold.
Using conversion factors, you do 11.82 g X 1 mol/196.6 g
The grams cancels out and you are left with 6.012 x 10^-2 mols
I put 6.012 since there are 4 significant figures given in your question, hence 11.82 grams.