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.

Molecules can only be used effectively for this purpose when they are above their Krafft temperature, and low concentrations of these form a layer named for Irving Langmuir and Katharine Blodgett. These substances are often added to fluids flowing through pipes to prevent corrosion, and they are added to windows and lenses to prevent them from fogging up. William Griffin and J. T. Davies devised measurements of the hydrophilic-lipophilic balance of these substances, based on the fact that molecules of these chemicals have soluble and insoluble ends. Name these chemicals, used in soaps, which lower surface tension.
Output:
Science