But caustic soda is a base with a pH of 14. It is a master of . The hydroxide ions from the soda attacked the fat molecules like a pair of molecular scissors. They sliced the big, stubborn grease into two smaller, water-soluble parts: glycerol (a soap-soft liquid) and fatty acid salts (which are, literally, soap).
She remembered the white granules under the sink: caustic soda, also known as sodium hydroxide. Her grandmother swore by it, but Marta had always been scared of the warning label: how does caustic soda unblock drains
After fifteen minutes, the hissing stopped. Marta filled the sink with hot tap water, pulled the plug, and watched the water spiral down with a clean, hungry gulp. But caustic soda is a base with a pH of 14
The drain was silent. And clear.