You will be given a definition of a task first, then some input of the task.
In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

The Petasis reagent contains an atom of this element at the center, and it coordinates to the two cyclopentadiene molecules in Tebbe's reagent. Another compound that contains this element and aluminum operates via the Cosee-Arleman mechanism, and this metal can be extracted via the Kroll process from rutile or ilmentite. In addition to its use in the Ziegler-Natta catalyst, this metal's tetrachloride is commonly used in organic reactions as a Lewis acid. Its dioxide is commonly found in paint. FTP, name this metal which is used in aerospace applications due to its durability, with atomic number 22 and symbol Ti.
Output:
Science