What Gas Does Vinegar and Baking Soda Make? The Simple Answer
The classic reaction between vinegar and baking soda produces carbon dioxide gas (CO₂). When the acetic acid in vinegar meets the sodium bicarbonate in baking soda, they react to form sodium acetate, water, and carbon dioxide. The bubbles you see are the CO₂ gas escaping, which is the same gas that makes soda fizzy and helps baked goods rise.
How the Reaction Works
Vinegar is a dilute solution of acetic acid, and baking soda is a pure base. Mixing them triggers an acid-base reaction. The chemical equation is: acetic acid + sodium bicarbonate → sodium acetate + water + carbon dioxide. The CO₂ gas is released rapidly, which is why the mixture fizzes and foams American Chemical Society. This reaction is often used in simple science experiments to demonstrate gas production.
A quick example: if you combine half a cup of vinegar with a teaspoon of baking soda in a narrow container, the foam can overflow within seconds. The carbon dioxide produced is heavier than air, so it can be poured like a liquid to extinguish a small candle flame. This same principle is used in some homemade volcano models, where the gas pushes the colored foam out Royal Society of Chemistry. For safety, avoid inhaling the gas directly, as it can displace oxygen in enclosed spaces.
The reaction stops once one of the ingredients runs out. If you add more baking soda to a mixture that has already stopped fizzing, no new bubbles appear because the vinegar has been used up. The leftover liquid is a solution of sodium acetate in water, which can be dried to form crystals. Sodium acetate has a practical use in hand warmers, where it releases heat when it crystallizes American Chemical Society. This byproduct is safe to pour down the drain in small amounts.
The same gas-producing reaction is used in some fire extinguishers. A small container of acid is broken inside the extinguisher, mixing with a sodium bicarbonate solution to generate pressurized CO₂ that pushes out the extinguishing agent Royal Society of Chemistry. Bakers also rely on the reaction when a recipe calls for buttermilk and baking soda. The lactic acid in buttermilk acts like vinegar, producing carbon dioxide bubbles that make pancakes and quick breads fluffy without yeast.
Key Takeaways
- The gas produced is carbon dioxide (CO₂), formed when acetic acid in vinegar reacts with sodium bicarbonate in baking soda.
- The reaction is fast and creates visible fizzing, making it a common demonstration for acid-base chemistry.
- Carbon dioxide from this reaction is harmless in small amounts but can be used to put out small fires or inflate a balloon if the gas is captured.
- Always perform the reaction in a well-ventilated area and avoid breathing in the gas directly, especially in confined spaces.
