Question

The reaction of Cr2O3 with silicon metal at high temperatures will make chromium metal. $$2Cr2​O3​(s)+3Si(s) 4Cr(l)+3SiO2​(s) The reaction is begun with 113.00 g of Si and 82.00 g of Cr2O3.

How many grams of the excess reactant are left after the reaction is complete?

Answer 1

Reaction of Cr₂O3 with silicon metal at Chronuicem metal. high temperatures produces 4Cyle) + 35102 (5) 2 CrąOz (5) + 351(5)-> 2 moles of chao reacts with a moles of si form 4 mole of cr and 3 role of sio₂. to in the The reactant reaction is which called is totally limiting consumed reagent. the reaction The is reactaut called which Excess is left after reagent. Molar mass of cr2O3 = 2x atauic mase - Он от + 3х аtеше майя а) охуем - 2x 52 + 3x16 - 104 + 48 = 152 Sus 2 mole of cr₂O3 → 3rude of si is needed.

(2x152) 9 6+ (0,02 → (3*28) 9 of si required 304 9 67 67293 84 9 of si required. 82.00 9 of 17203 - ?? 82.00 X 84 Mass at si Tequired = 304 = 22.657 3 = 22.669 113.00 g of 22.66 g of si required. But can Si is present. si present excess required. and silicon is excess reagent amount of si left after reaction (13.00 - 22.66) 4 = 90.349