AP Chem Solutions has released version 2.0 of our app in Google Play and the App Store. The new edition is organized by units. Each unit comes with additional notes for all lessons and two multiple choice practice tests. After answering a multiple choice question, you are provided with a detailed explanations of the concepts and procedures needed to solve that problem. These tests will help you build your knowledge while practicing the types of problems that you will encounter when writing the AP Chemistry Exam.