My Absolutely Fabulous Slide Show on Chemical Reactions, So Yah!!! By Rachel Mills A Chemical Reaction • The Definition of a Chemical Reaction is this: A process that involves changes in the structure in the energy content of atoms. (Simplified version from Dictionary.com) A Written Example • As you can see here we have a chemical equation here. Also listed here are the reactants and products. This is the equation of photosynthesis. • Equation: 6CO2 + 6H2O= C6H12O6 + 6O2 • Reactants • • • • Carbon Dioxide Oxygen Light Energy Hydrogen • Products • Glucose • Water + Oxygen The Law of Conservation of Matter • The definition is just what is says. Conservation of Matter. It states that matter cannot be destroyed or created. Thus meaning it conserves all matter in existence. Though it may change its form, it is still the same matter. More on the Chemical Reaction Example. • Now, we are listing the atoms found in our example equation. We will again be listing them in reactants and products. • Equation: 6CO2 + 6H2O= C6H12O6 + 6O2 • Reactants • 6 Carbon Dioxide Molecules • 6 pairs of Hydrogen Atoms • 6 Oxygen Atoms • Products • • • • 6 Carbon Atoms + 12 Hydrogen Atoms + 6 Oxygen Atoms = (Glucose) 6 pairs of Oxygen Atoms The end is the same as the beginning. Say you have 6 lbs. of Celery… • When you eat 6 pounds of Celery, you expect it to be good for you. But you will gain 6 pounds all the same. Too much of something good can be bad. Say you have 6 lbs. of Steak… • The same also applies. If you eat 6 pounds of Steak, you will still gain those 6 pounds. Protein is good for you, but eating 6 pounds of it may mess with your digestive system. As well as eating all of that celery. So in conclusion the end is the same as the beginning, you will still have 6 pounds of food whether you eat Celery or Steak. Mass problem. • The following problem will be solved below the problem. • Stu has a liquid and a solid that together have a mass of 200 grams. When he mixes the two together in an open cup it starts to bubble. He then finds the mass of the stuff in the cup. Why is the mass only 160 grams now? • The answer is simple, When he mixes the solid and the liquid together they are still 200 grams. But when is starts to bubble some of the gas escapes. 40 grams of gas or part of the mass; leaves the container. So only 160 grams of the mass remain. Another Question • Here is the next problem: • When Rene drives her car the gasoline reacts with oxygen to make carbon dioxide and water. If Rene uses 20 lbs of gasoline and 5 lbs of oxygen how many pounds of water and carbon dioxide will there be together? • As said in the Law of the Conservation of Matter, no matter can be destroyed or created. So 20 lbs of gasoline and 5 lbs of oxygen are put together there would be 25 lbs of water and carbon dioxide total. Its as simple as addition.