| Rates of Reaction | ||
| #1 | For a collision to be effective, the molecules must hit with enough energy and ________________________. | spatial orientation |
| #2 | A decrease in temperature would _______________ the rate of a reaction. | decrease |
| #3 | Adding a catalyst speeds up a reaction by ______________ the activation energy. | lowering |
| #4 | Which reacts faster with 1.0 M HCl: 1g chunk of zinc or 1g of zinc powder and why? | 1g zinc powder b/c more surface area |
| #5 | What will react faster: ionic solids dissolved in water or covalent solids dissolved in water? | ionic solids dissolved in water |
| Potential Energy Diagrams | ||
| #1 | The amount of energy to get from the reactants to the activated complex | activation energy |
| #2 | If the products have more energy than the reactants, the reaction is: exo or endo? | endothermic |
| #3 | The difference between the potential energy of the products and the reactants is called | heat of reaction |
| #4 | Which particle is at the top of the hill | activated complex |
| #5 | When a catalyst is added it provides a(n) _______________ pathway for the reaction to occur. | alternate/new |
| Table I | ||
| #1 | Is the formation of C2H2 exo or endothermic? | endothermic |
| #2 | Is the decomposition of Al2O3 exo or endothermic? | endothermic |
| #3 | When the equation for forming C2H6 is re-written, which side would the heat be included on? | the right |
| #4 | How would the dissolving of NaCl feel? What would happen to the temperature? | feels cold, temperature decreases |
| #5 | How many kJ of heat are released when 10 moles of Al react with oxygen to form Al2O3? | 8377.5 kJ released (H = -8377.5 kJ) |
| Entropy and Spontaneitiy | ||
| #1 | Define entropy. | disorder/randomness/chaos |
| #2 | Name a phase change that would be a decrease in entropy. | gas to liquid to solid |
| #3 | Sublimation would be a(n) ____________ in entropy. | increase |
| #4 | Does entropy increase or decrease in the following reaction? C3H8(g) + 5O2(g) --> 3CO2(g) + 4H2O(g) | increase |
| #5 | For a reaction to always be spontaneous, the entropy must _____________ and the energy must ______________. | increase, decrease |
| Equilibrium | ||
| #1 | At equilibrium, rates of the forward and reverse reactions are _______________ and the concentrations of reactants and products are ______________. | equal, constant |
| #2 | There is phase equilibrium for H2O(s) <--> H2O(l) at what temperature in K? | 273 K |
| #3 | A ___________________ solution is at equilibrium. | saturated |
| #4 | When pressure is increased on a chemical reaction at equilibrium, the reaction shifts to the side with _______________________. | less moles of gas |
| #5 | Adding a catalyst (will/will not) shift equilibrium. | will not |
| Final Question | |
| Explain, in terms of LeChatelier's Principle, why decreasing the concentration of N2 causes a decrease in NO concentration for the following equation. N2 + O2 <--> 2NO | The reaction shifts to the left, decreasing the product NO. |