"In our session today, I helped the student prepare for his AP Chemistry test tomorrow. The test will be covering chemical kinetics and nuclear chemistry. He felt that he had a good understanding of chemical kinetics, so we only briefly discussed those concepts (mostly how to distinguish a zero-order, first-order, and second-order rate laws based on graphs alone). We spent most of our session focusing on nuclear chemistry. The toughest part of that chapter for him were the concepts of half-life and radioactive dating. The first problem that we reviewed together was quite tricky and involved an extra step that was never discussed in the text book. We talked about it multiple times so that he would be sure to recognize a problem like that on his test and know what to do. We practiced many different radioactive dating problems, solving for different variables. These problems are difficult because they are word problems, so you must first figure out what information has been given and what information you are solving for. Also, often they give you different units that you must convert. Sometimes these problems have extra steps too, once you've found the answer, or before you can start, to convert from the mass of a larger molecule to just the element that is undergoing decay. For these reasons, it is very easy to make mistakes somewhere in the problem-solving process. It took us most of the session to smooth out these mistakes and make sure that he had a clear understanding of how to solve these kinds of problems. By the end, he seemed to really understand the concepts and was thus better able to solve the problems and know what to look out for. At the end of the session, we discussed study techniques for chemistry that can help him do well on his tests."