Summary Mixing baking soda and vinegar produces a gas (carbon dioxide). An basic acid-base reaction. Science content Chemistry: States of Matter, Properties of Materials (K-7) Chemistry: Atoms, Molecules (3-7) Chemistry: Chemical Changes (2, 7) Lessons activity is in Chemical reactions Making gases Chemical reactions with baking soda Resource Indigo Instruments Materials baking soda vinegar tub to contain the reaction optional: molecule models of the reaction - need 2 Hs, one C and 3 Os per group Procedure Mix the baking soda and vinegar - this may be a familiar reaction to some. It makes bubbles of gas. Tell students the chemical reaction that produces the gas, or give students molecule models of the starting molecules and they figure out what the products are (tell them one product is water if necessary): HCO3 (baking soda, or base) + H (vinegar, or acid) -> H2O (water) + CO2 (carbon dioxide gas) The molecule models can be purchased (see resource), or made from modelling clay and toothpicks. This chemical reaction is endothermic - it absorbs heat, so feels cold. A temperature change is an indicator that a chemical reaction is happening. The baking soda and vinegar reaction is the basis of many science activities, including setting off rockets and making food. Grades taught Gr K Gr 1 Gr 2 Gr 3 Gr 4 Gr 5 Gr 7