When 38.21 g of pure copper reacts with 192.83g of iodine, 190.83g of a compound containing only

copper and iodine result. 40.21g of iodine remain when the reaction is complete.
a. Do these results support the Law of Conservation of Mass? Explain.
b.does this compund obey the laws of multiple porportions? Explain.

im not sure exactly how to answer this question, would the 40.21 be subtracted from the 190.83?

1 answer

mass reactants:
38.21 + 192.83 = 231.04 g.

mass products + left over:
190.83 + 40.21 = 231.04 g.

Looks to me like mass reacts equals mass product plus the left over so mass is conserved.