Caustic Soda is used to increase pH in muds. Increase pH with Caustic Soda precipitates magnesium (Mg2+) and suppresses calcium (Ca2+) high hardness such as seawater, and neutralizes acid gases such as carbon dioxide and hydrogen sulfide. It can soluble in water and reacts violently with water, then gives off extreme heat. For this reason, Caustic Soda should be added to water very slowly with sufficient agitation to prevent violent boiling or spurting.