A) the change in the internal energy of a system that absorbs 2,500 j of heat and that does 7,655 j of work on the surroundings is j.

b) the δe of a system that absorbs 12.4j of heat and does 4.2 j of work on the surroundings is j.

Which of your 24 wells had indications that a chemical reaction occurred? how were you able to tell that a chemical reaction occurred? which of your 24 wells had indications that a physical reaction occurred? how were you able to tell that a physical reaction occurred? report on both mixing and evaporation. make a general statement about whether your hypotheses were validated or rejected. must your hypotheses be correct for this to be a successful laboratory?