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Kinetics AP Chem
Kinetics and Rates
| Question | Answer |
|---|---|
| Define the collision theory | When two chemicals react, their molecules have to collide with each other with proper energy and orientation |
| What is the probability that two molecules will react? | The chance of the collision in the proper orientation with the proper energy is about 1/2. |
| Will five molecules in the same equation ever react in one step? | No, the probability is almost impossible! |
| What are elementary steps? | Series of smaller steps that eventually lead to the overall reaction. |
| Define intermediates | Species that are created during the elementary steps of the reaction, but are not a part of the overall reaction. They are products, and they are consumed as reactants immediately. |
| What are catalysts? | Catalysts speed up chemical reactions by decreasing the activation energy required. They are reactants, and they come out as products in the overall reaction. |
| Reaction mechanisms are the ones that determine the rate law because they are | slow |
| What is activation energy? | The amount of energy required to initiate a chemical reaction. In exothermic reactions, the overall will be greater than the initial, and in endothermic, it will be less than the activation energy. |
| Zero order reactions are not dependent on | concentration |
| The graph for zero order reactions are: | rate=k (-k) |
| In second order reactions if the concentration doubles the rate will | quadruple or do the square of what the concentration did |
| The graph for second order reactions are: | t vs. 1/(A) and the slope= k |
| In first order reactions if the concentration doubles the rate will | double |
| The graph for first order reactions are: | t vs. ln(A) and the slope is -k |
| What equation will be used to find the activation energy? | Arrhenius' Equation |
| Which factors affect the rate? | Temperature, surface area, concentration, the use of catalysts, if the compound is ionic, or if it is in aqueous form |
| How are rate laws determined (experimentally or theoretically)? | Using experimental data, so experimentally |
| Why do ionic substances react faster? | They break into ions, unlike covalent substances |
| How do you determine the overall reaction order? | Add all the exponents of the orders together for the overall |
| Write the rate law for a first order reaction using A and B, if the rate doubles when A is doubled, and the rate stays the same when B doubles | rate= k(A)^1(B)^0 |
| Write the basic steps used to find slopes in a calculator | 1. Stat, Edit 2. Enter Data 3. Stat, Calc 4. LinearRegression |
| The rate law graphs correspond to which easy, and famous graph? | Linear graphs y= mx +b |
| What are unimolecular reactions? | When only one molecule is reacting. |
| What are bimolecular reactions? | When two molecules are reacting. |
| What are termolecular reactions? | When three molecules are reacting. |
| Why are termolecular reactions uncommon? | The chances of two molecules reacting are only 1/2, three are even less than that. |
| Is 2NO + O a bimolecular or termolecular reaction? | Termolecular because there are three molecules in total. The coefficient must be accounted for. |