Sun's

page about SCJP 5 says:

Details

Delivered at: Authorized Worldwide Prometric Testing CentersPrerequisites: NoneOther exams/assignments required for this certification: NoneExam type: Multiple choice and drag and dropNumber of questions: 72Pass score: 59% (43 of 72 questions)Time limit: 175 minutes

As part of our exam refresh process, SUN occasionally tests new questions on the live exam forms. These questions are tested to understand their statistical properties and will not be counted as part of your final score. There are 10 unscored questions in this exam. Forty extra minutes have been added to your exam duration to allow you ample time to answer all questions.

So, normally the exam would be 72 questions and takes 175 minutes (2:55). But now there are 10 extra, unscored questions, so there is a total of 82 questions. You get 40 minutes extra time for the extra questions, so the total time will be 215 minutes (3:35).