What are a couple of chemical reactions?
Any change to a substance that cannot be “undone” to get back the same substance and where you end up with one or more different substances than you started with is indicative of a chemical reaction. Think of all of the things you could do to a piece of paper that WOULDN’T give you paper in the end: Burning it or dissolving it in acid wouldn’t give you paper in the end, so those are chemical reactions. In fact, burning anything will be a combustion reaction, which is chemical. Any time you change a substance by introducing acids or bases will also be a chemical reaction. Vinegar (acid) and baking soda (base) is a good example as well. Because you can see bubbles when the two substances are mixed, you know a new substance was made – a gas. That’s why the bubbles are there. This is an example of an acid-base chemical reaction. The sodium and water reaction someone mentioned is an acid-base reaction as well. Sodium is a strong base and water is slightly acidic, unless it’s distilled water
