| A | B |
|---|
| first type of chemical equations | synthesis equation-describes a reaction where 2 or more simple substances combine to form a new complex substance1 |
| second type of chemical equation | describes a reaction where 1 substance breaks down into 2 or more simpler substances |
| third type of chemical equation | single displacement equation describes a reaction where 1 element replaces another element |
| fourth type of chemical equation | double displacement equation describes a reaction where a preipitate is formed;2 elements switch places |
| example of synthesis equation | A+B->C (AB)or Hydrogen +oxygen>water |
| example of decomposition equation | ABC>AB + C |
| example of single displacement equation | AB + C > AC + B |
| example of double displacement equation | AB + CD > AD + CB |
| first type of reaction | exergonic(light or sound energy is given off |
| second type of reaction | exothermic-heat energy is given off |
| third type of reaction | endergonic-light or sound energy is absorbed |
| fourth type of reaction | endothermic-heat enrgy absorbed |
| example of exergonic reaction | light necklace |
| example of exothermic reaction | fire |
| example of endergonic reaction | photosynthesis |
| example of endothermic reaction | cold packs |
| first step to balance equation | read the problem: some hydrogen plus some oxygen yields water |
| 2nd step:describe in symbols | H2 + O2=H2O |
| 3rd step: count atoms for each element | 2 atoms of H, 2 atoms of O on reactant side; 2 atoms of H on product side |
| 4th step: ad coefficients | 2H2 +O2 = @ H2) |
| last step:see if balanced | 4 atoms of H on each side; 2 atoms of O on each side measn they ARE balanced! Get It?? |
| coefficients | numbers which represent the number of molecules of each substance in a reaction; THEY ARE THE ONLY NUMBERS THAT CAN BE CHANGED WHEN BALANCING EQUATIONS!! |
| GET IT??? | I HOPE SO!!! |
