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 Schlenk equilibrium, which can be affected by the presence of dioxane, describes the stability of these compounds, whose synthesis can be improved by the addition of mercuric chloride amalgamates. They react with nitriles to form intermediate imine anions, and dry carbon dioxide can be bubbled through them to create carboxylic acids, which themselves do not form an addition product with these. In what is sometimes called their namesake's reaction, they act as strong nucleophiles to form tertiary or secondary alcohols from ketones or aldehydes. For 10 points, name these compounds formed by reacting an alkyl halide with magnesium, named for a French guy.
Science

The future Byzantine Emporer Romanus II was at one time betrothed to his niece Hedwig, and his son married Theophano, who was either the daughter of the same Romanus II or the niece of John Tzimices. The son of Henry I, Duke of Saxony, he defeated the Magyars at the Battle of Lech in 955 and was crowned Holy Roman Emperor in 962. For ten points, name this founder of the dynasty that bears his name.
History

When in solutions of these substances, colloid particles can be pushed together by an osmotic imbalance known as the depletion interaction, and in low concentrations these substances can cause bridging flocculation. When in a theta solvent, these substances follow a random flight model. More generally, their interactions in solution are modeled by Flory-Huggins theory. These substances can be synthesized with the help of Ziegler-Natta catalysts. For 10 points, name these large molecules such as Kevlar and nylon which are made up of many repeating monomers.

Science