2) In science Jose left 15g of steel wool (Fe) on his lab scale for several weeks. He noticed over time that the steel wool changed color to a dark reddish brown, became
very brittle, and increased to 25g of mass. Jose’s science teacher told him that he no
longer has steel wool, but now has iron oxide (Fe 2 O 3 ) or “rust” because the iron reacted
with the oxygen (O 2 ) in the room.

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)