Can someone give me the answers?

219 grams of iron (iii) oxide reacts with excess carbon according to the reaction equation shown below. fe2o3 + c → fe + co2 after a scientist performs the chemical reaction they find the actual yield of iron to be 57.4 grams. calculate the percent yield of this chemical reaction.

Which produce would best increase the amount of heat energy that is actually gained by calorimeter b

Use examples from the article to explain one positive and one negative effect that chemistry has had on society.