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.

[Q]: The Soave equation adds an acentric factor to this statement, and the virial equation measures deviations from this law using a compressibility factor. This law derived by Benoit Clapeyron can account for density in its "dirty mop" form, and when A and B terms are added to account for the volume and interactions between particles, it is called van der Waals equation. Containing a namesake constant that is Boltzmann's constant times Avogadro's number is, for 10 points, what law usually stated as PV equals nRT
[A]: Science

[Q]: This man gives his name, along with that of Francis Sears, to a process in ultrasonic imaging for which the acoustic wavefronts act as optical gratings to diffract the light on either side of the central spot. The distance over which charge carriers in plasmas exclude electric fields via his namesake shielding is also known as his namesake length. With an assistant later famous in his own right for his rule for determining whether ring molecules would show aromatic properties, he developed a mathematical expression to explain characteristics of electrolytic solutions, the famous equation named for him and Erich Hckel. FTP name this man who also gives his name to the SI unit defined as about 3.3 x 10-30 Coulomb meters, which measures the molecular dipole moment.
[A]: Science

[Q]: One leader in this conflict was killed in the second battle of Ramla and was named Stephen II. Another figure in this conflict was named Peter the Hermit. This conflict was chronicled by Robert the Monk. This campaign began after a speech given by Pope Urban II at the Council of Clermont. A key battle in this conflict ended when a (*) Fatimid leader fled a certain holy city. For 10 points, name this military conflict in which Europeans sought to regain control of Jerusalem, which was the original campaign of this type.
[A]:
History