2. Which of the following are examples of an exothermic chemical reaction? Check all that apply. A: photosynthesis B: burning a piece of wood C: freezing water into ice D: none of the above

3. Any type of reaction that invovles burning (combustion) can be classified as which of the following types of reactions? A: synthesis B: endothermic C: exothermic D: all of the above

4. Burning sugar is an exothermic process. A: True B: False

5. Can a chemical reaction be both exothermic and endothermic? A: Yes B: No

6. What term is given to a reaction which transfers heat energy to the surroundings? A)Endothermic B)Reversible C)Exothermic

7. On a reaction graph, what does the height of the hump represent? A)The activation energy B)The energy change C)The energy released when new bonds are made

8. When barium hydroxide and ammonium chloride react, the temperature of the mixture decreases. What kind of reaction is this? A)Endothermic B)Decomposition C)Exothermic

9. What can you deduce from the reaction profile below? A)The reaction is endothermic B)A catalyst is present C)More energy is released than absorbed

10. When calcium reacts with water, the temperature changes from 18°C to 39°C. Which statement is correct? A)The solution at the end is acidic B)The reaction is exothermic C)The reaction is endothermic

11. If a reaction releases more energy when new bonds are made than the amount of energy absorbed to break bonds in the reactants, which statement is true? A)It is endothermic B)It is exothermic C)It is very slow