What is the theoretical yield of li3n in grams when 12.7 g of li is heated with 34.7 g of n2

12.7 g Li*(1 mole Li/6.94 g Li)=1.83 moles of Li
34.7 g N2(1 mole N2/28 g N2)=1.23
1.83 moles Li*(2 moles Li3N/6 mole Li)(34.82 grams Li3N/1 mole Li3N)=21.24g Li3N

Ithinks its false. tell me if im wrong

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.