| A | B |
|---|
| Synthesis reaction | Two or more elements or compounds combine to make a more complex substance |
| Decomposition reaction | Once compound breaks dow into simpler substances. |
| Single replacement reaction | When one element replaces another in a compound. |
| Double replacement | When the atoms in two different compounds trade places. |
| Chemical change | Occurs when there is a change in the matter produced; one or more new substances are made; cannot get the original substances back. |
| How many atoms of hydrogen are there in 2 molecules of CH4 | 8 atoms of hydrogen |
How many atoms of hydrogen are there in 4 molecules of C6H12O6| 48 atoms of hydrogen | |
| chemical equations | a way to show a chemical reaction using symbols instead of words |
| The arrow in a chemical equation is read as | "yields" or "reacts to form" |
| law of conservation of mass | in a chemical reaction, matter is not created or destroyed, it just changes form. |
| open system | matter can escape from or escape to the surroundings |
| closed system | matter cannot enter or leave the system |
| coefficient | a number placed in front of a chemical formula in a chemical equation |
| Exothermic reactions | the products have less energy than the reactants |
| Endothermic reactions | the products have more energy than the reactants |
| Activation energy | the minimum amount of energy needed to start a chemical reaction |
| concentration | the amount of substance in a given volume |
| catalyst | increases a chemical reaction by lowering the amount of activation energy needed |
| enzyme | a biological catalyst found in living things |
| inhibitor | a substance that slows down a chemical reaction |
