Why does baking soda and vinegar not mix?
They do mix ! That’s why there is a reaction. The baking soda mixes with and comes in contact with the acetic acid and water (vinegar) and the resulting ions react vigorously to produce Carbon Dioxide. Since this happens in the blink of an eye, you might conclude that they weren’t mixing. If there were no chemical reaction, they would indeed “mix” like adding sugar or salt to water.