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Part I : Answer the following showing all work and/or in a clear and concise manner.
1. What is the difference between temperature and heat?
2. What is the definition of activation energy (Eac)?
3. Potential energy of the reactant (PEr) is _________ compared to the potential energy of the product (PEp).in an Exothermic rxn.
4. ___________________ is the average kinetic energy of all the particles in a substance.
5. State the two parts to "our" definition of the 2nd Law of Thermodynamics.
6. Absolute zero is the condition where __________________________. The condition of absolute zero is _________________ and _________________.
7. Entropy is the measurement of _______________________________
8. If a system (for example water) has a delta H that is "-", the system (i.e. water) would be releasing or absorbing energy/heat? Circle correct answer.
9. What is a spontaneous reaction in Thermo? What thermodynamic property deals with it (it needs to be negative for the reaction to be spontaneous.)
10. What two "ways" can a reaction stop (i.e. no more product is made)?
11. deltaG, Gibbs Free Energy change is composed of two other Thermodynamic properties. What are these properties.
12.Can spontaneous reactions be endothermic reaction also, yes or no? Explain.
13. How does the concept of Entropy affect or explain one or more of the conditions for absolute zero?
14a. Explain the difference between a Relative temperature scale (i.e. Celsius) and Absolute temperature scale (i.e. Kelvin).
14b. Someone stated that "energy was lost in the chemical reaction". State if you agree or disagree with that statement. Justify your answer using your knowledge of Thermo.
14c. What type of energies compose Enthalpy?
Math Concept
Part II Dimensional Analysis / Heat Equation Problems
Answer the following questions showing all work as discussed in class/notes. Please answers questions on a separate sheets of paper where there can only be 3 problems per page (a page is front and back so that means you will need to use 2 sheets of paper).
15. SpongeBob SquarePants wanted to go on a diet and he lost 4.2E3 mL/hr of water. If he was on the diet for 2.56 days, how many gallons of water did he lose? (1 gal = 3.785 L ). Flow rate equation R = V / t where R - flow rate, V - volume and t - time.
16. How much heat (in kcals) is required to raise the temperature of 675ml of water from 35.6degC to 62.9degC?
17. What is the mass of olive oil if you added 5.1kJ to the oil (making some deep fried chicken, thanks for recipe Rachel Ray!!) and the oil's temperature raised from 63.2degC to 87.3degC? (coil = 1.97J/(g degC) ).
18. What is the specific heat of a substance if the temperature of the substance is raised from 15.2degC to 47.3degC by adding 14.1kcal of heat energy. The mass of the substance is 2.3 kg. Please put answer in cal / (g degC).
19. A reaction runs in a calorimeter and absorbs 7.41E4 J of energy. This causes the temperature of the water in the calorimeter to drop from 25.0degC to 12.5degC. What is the mass of the water?
20. The stored energy in foods is usually measured in Calories (which are 1000cal). One gram of peanut oil releases 8.84 Calories when it is burnt. If that one gram of peanut oil is burned in a calorimeter containing 500.g of water at 25.degC, what will the final temperature of the water be?
21. A 400.0g sample of water at 25.0degC absorbs 15.89kJ of energy. What will be the final temperature of the water?
Answer for Part II:
15) 68gals 16) 18.4kcals 17) 110g or 1.1E2g 18) 0.19cal/(g-degC) 19) 1.42E3g 20) 43degC 21) 34.5degC