In a reaction, your actual product had a mass of 11.9 grams. You calculated that you need 15.0 grams to have the reaction go to completion. What is your percent yield?

let that person have a turn to speak : )

because of all the things that happen around the us, many people get into arguments which sadly could get physical, but we should actually make a change for that.

i think it's letter a.

nuclear fission produces elements that are heavier than helium.

the elements that are used in nuclear fission and their products are much heavier than helium.