Teacher: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.
Teacher: Now, understand the problem? Solve this instance: This element catalyzes the addition of alpha-bromo esters to ketones in the Reformatsky reaction. This element is coordinated by a water atom and three imidazole nitrogens in the active site of carbonic anhydrase, and transcription factor II B has a "ribbon motif" named for this element. A structure with folds called the (*) "gag knuckle" and "treble clef" uses cysteine and histidine residues to bind an ion of this metal, its namesake "finger" domain. Its most often used ore is its sulfide, the mineral sphalerite. With nickel, this metal is used in rechargeable batteries. For 10 points, name this metal, which with a thin copper coating comprises pennies.
Student:
Science