Task: Text Categorization
Input (English): Ninhydrin forms a Schiff base with this chemical, resulting in a hue known as Ruhemanns purple. The Birch reduction takes place in a liquid substrate of it, the reason it is common in methamphetamine labs. The Kjeldahl method uses this molecule as an end-product to measure the amount of nitrogen in a sample, and it is oxidized in the first step of a nitric acid forming procedure, the Ostwald process. For 10 points, name this weak base found in fertilizers, formed by combining hydrogen and nitrogen in a three-to-one ratio in the Haber process.
Output (English): Science