An introductory ethics exam may cover major concepts in ethical theory, such as the differences between deontology and consequentialism. Other items may include Kant's categorical imperative, Mill's utilitarianism, Singer's animal liberation and Rawl's notion of justice.
The questions on an ethics exam are typically determined by the philosophical traditions your professor considers important or the guidance of a textbook. Because ethics covers a wide range of concepts, a good predictor for the types of questions on an ethics exam is the material covered in your specific course.
Other general questions common in ethics courses ask about the differences between right and wrong, good and bad, and morality and ethics. What confers moral status or what makes one a member of a moral community are common considerations for formulating questions in courses influenced by American pragmatist ethics courses. Questions about the differences between relativism and absolutism might be included in your exam, and a professor or pre-written exam may prompt the student to argue for one or the other. Another contemporary idea that is likely to be considered is whether science can determine a moral code or ethical theory; whether, as David Hume asked, an "ought" can be derived from an "is."