When baking soda is added vinegar what are the bubbles that formed made of?

The bubbles formed when baking soda (sodium bicarbonate) is added to vinegar (acetic acid) are made of carbon dioxide gas (CO2).

Chemical Reaction:

When sodium bicarbonate (NaHCO3) and acetic acid (CH3COOH) come into contact, they undergo a chemical reaction. Sodium bicarbonate is a base, while acetic acid is an acid. When these two substances react, they form carbon dioxide gas (CO2), water (H2O), and sodium acetate (CH3COONa). The chemical equation for this reaction is:

NaHCO3 + CH3COOH → CO2 + H2O + CH3COONa

In this reaction, the sodium bicarbonate and acetic acid react to form carbon dioxide gas. The gas is released as bubbles, causing the mixture to fizz.