Adisease-resistant variety of a sexually reproducing crop was planted on a field with an existing nonresistant variety. after a few years, pests severely attacked the plants. the older, nonresistant plants died. however, the recently grown plants survived. why did the new plants survive?

Ammonium perchlorate nh4clo4 is the solid rocket fuel used by the u.s. space shuttle. it reacts with itself to produce nitrogen gas n2 , chlorine gas cl2 , oxygen gas o2 , water h2o , and a great deal of energy. what mass of nitrogen gas is produced by the reaction of 2.1g of ammonium perchlorate?