<?xml version="1.0" encoding="utf-8"?><mads xmlns="http://www.loc.gov/mads/" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mads/
mads.xsd"><authority><topic authority="http://AATesaurus.cultura.gencat.cat/aat/getty_en">sodium carbonate</topic></authority><related type="narrower"><topic>natron</topic></related><related type="broader"><topic>sodium compounds</topic></related><variant type="other"><topic>sal soda</topic></variant><variant type="other"><topic>soda</topic></variant><variant type="other"><topic>soda ash</topic></variant><variant type="other"><topic>soda crystal</topic></variant><variant type="other"><topic>washing soda</topic></variant> <note xml:lang="en"><![CDATA[ An anhydrous grayish-white, odorless, water-soluble powder, NA2CO3, usually obtained by the Solvay process and containing about 1 percent of impurities consisting of sulfates, chlorides, and bicarbonates. It is used in the manufacture of glass, ceramics, soaps, paper, petroleum products, as a cleanser, for bleaching, and in water treatment. ]]></note></mads>