What acid is made up of baking soda and vinegar?

When baking soda (sodium bicarbonate) and vinegar (acetic acid) are mixed, they undergo a chemical reaction to produce carbonic acid (H2CO3). Carbonic acid is an unstable compound that quickly decomposes into water (H2O) and carbon dioxide gas (CO2). The chemical reaction can be represented as follows:

NaHCO3 (sodium bicarbonate) + CH3COOH (acetic acid) → H2CO3 (carbonic acid) + NaCH3COO (sodium acetate)

The sodium acetate is a salt that remains in the solution, while the carbon dioxide gas escapes as bubbles, causing the characteristic fizzing and foaming observed when baking soda and vinegar are mixed.