A chemical reactions occurs when two or more molecules in an original substance rearrange and form a new substance. Many chemical reactions are irreversible. Meaning, once the reaction has occurred and created something new, you can not turn it back into the original substance. Chemical reactions are composed by a chemical equation. It starts with the reactants, the substances that react, and then ends with the product, the new substance. When the new product is formed, not only is the chemical composition changed but so is the physical appearance. Chemical reactions can be found in our everyday lives through cooking, rusting, and/or inside our body.
Chemical reactions can be found in our everyday lives through cooking. For instance, say you bake chocolate chips cookies. You start off with a light colored moist and sticky dough like texture and after you put in the oven for some time and then take it out, you now have a dark and crunchy cookie. Thus occurred due to the products mixed inside the cookie dough. First you can start off with butter. The butter melts which flattens the cookie and then the water that was trapped inside of the butter starts to evaporate which causes steam and that causes the cookie to begin to rise. At a certain temperature, the water completely evaporates and leaves the cookie without moisture which causes it to be dry. The heat that is released from the oven causes the cookie to appear darker and have cracks. Therefore, and in the end, the heat caused the whole cookie to change its chemical composition from a doughy mess to a hard texture.
Furthermore, chemical reactions can be found in our everyday lives by things that rust. For example, say you have nuts and bolts that has been fixated into the fence on your lawn. The nuts and bolts go through a lot considering that is outside and it has to go through the weather changes. It gets rained on time and time again and eventually it starts to turn a reddish brown color. That is rust. Rusting takes place when something that contains iron, which is a pure element, and oxygen comes into contact with water or moisture from the air. It then creates iron oxide. Iron oxide makes the substance appear that reddish brown color. Rusting can also take place when iron comes in contact with chloride, which then make the substance have a greenish color.
Lastly, chemical reactions can be found in throughout our body. Metabolism is the word use for when chemical reactions happen in our body. According to britannica.com, metabolism is the sum of the chemical reactions that take place within each cell of a living organism and that provide energy for vital processes and for synthesizing new organic material. For example, the saliva in your mouth is a type of enzyme. Enzymes speed up the process for chemical reactions. It breaks down the food that travels throughout the body. It causes the food to break down into easier pieces for your digestive system.
Subsequently, chemical reactions can be found in our everyday lives through cooking, rusting, and/or inside our body. They are different from physical changes because physical changes only change the appearance. Whereas, in a chemical reaction, the appearance and the composition are affected. So the next to someone bakes a cookie or sees iron rusting, they now know that it is a chemical reaction.
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