I. Calculators are not permitted on the multiple-choice sections of the AP Chemistry examination.
This recent change is due in part to the recent rapid expansion of scientific calculators' capabilities, which now include not only programming and graphing functions but also stored equations and other data. For the section of the exam in which calculators are permitted, students should use the calculators with which they are familiar, with as few limitations as possible. Nevertheless, they should not have access to information in their calculators that is not available to other students, if that information is needed to answer the questions.

II. Calculators are allowed on the free-response section for the first 40 minutes. During that time, students will work on one required problem plus one problem chosen from a pair of other problems. For the last 50 minutes, calculators must be put away as students work on the remaining free-response questions.
For the first 40 minutes, any programmable or graphing calculator may be used, with a few exceptions, and students are not required to erase their calculator memories before and after the examination. Although most calculators are permitted on the free-response section, calculators may not be shared with other students and those with typewriter-style (qwerty) keyboards will not be permitted on any part of the examinations.
The free-response sections emphasize solving in-depth problems and writing essays where knowledge of which principles to apply and how to apply them is the most important aspect of the solution to these problems.

III. Tables containing commonly used chemistry equations are provided with each examination for students to use when taking the free-response section.
The lists of equations may NOT be used when taking the multiple-choice sections. In general, the equations for each year's exam will be printed and distributed with the Course Description at least a year in advance so that students can get used to using them throughout the year. However, since the equations will be provided with the exams, students will NOT be allowed to bring their own copies to the examination room.
One of the purposes of providing these equations is to make the free-response sections equitable for those students who do not have access to equations stored in their calculators. The availability of these equations means that in the scoring of the free-response sections, little or no credit will be awarded for simply writing down correct equations or for ambiguous answers unsupported by explanations or logical development.

IV. Starting in 1999, a change will be implemented in the way that students choose among essay questions in Section II of the examination.
Through 1998, students are required to answer one essay (question 5) and then choose to answer two from among four essays (questions 6-9). In the new format there will be two required essay questions, and students will choose a third question from a pair of other essays. Importantly, one of the required essays will always be related to laboratory, while the topic of the other required essay will vary from year to year. The time allotted for answering the chemical reactions question and the three essays will remain the same.

Summing Up
The purpose of minimizing numerical calculations in both sections of the examinations and providing equations with the free-response sections is to place greater emphasis on the understanding and application of fundamental chemical principles and concepts. For solving problems, a sophisticated programmable or graphing calculator, or the availability of stored equations, is no substitute for a thorough grasp of the chemistry involved. The upcoming implementation of a required essay on a laboratory topic places greater emphasis on the important knowledge and skills that students gain in the laboratory.