Baking Soda's chemical name is sodium bicarbonate. In the US most of what's sold in grocery stores comes from a natural ore called "Trona" that's primarily mined in Wyoming. That ore is processed chemically to obtain the end product, so in a sense ALL baking soda is synthetic to some degree ("synthetic" is a derivative of the word "synthesize"). Here's what Grok had to say when asked "Where does food grade sodium bicarbonate come from?":

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Food-grade sodium bicarbonate, also known as baking soda, primarily comes from two sources:

Natural Mining: The majority is mined from trona ore, a naturally occurring mineral found in large deposits, such as in Green River, Wyoming, USA. Trona is processed to extract sodium carbonate (soda ash), which is then converted into sodium bicarbonate through a chemical reaction with carbon dioxide and water.

Synthetic Production: It can also be produced synthetically via the Solvay process, where sodium chloride (salt), ammonia, and carbon dioxide are reacted in water to produce sodium bicarbonate and ammonium chloride. This method is less common for food-grade products due to higher costs and the availability of natural sources.

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