U10 Quiz Review

1. U10 Quiz Review APC MM 12-13

2. You have a sample of X and you will be looking at adding heat to it. What information is needed to be able to calculate the amount of heat actually added to the substance X?

3. Type of substance • Specific heat • Mass of substance • Temperature change

4. Define heat of vaporization. • Define heat of fusion.

5. Heat of vaporization is the energy added when a liquid is changed to a gas. It could also be heat energy given off when a substance condenses. • Heat of fusion is the energy added to a substance to melt it. It could also be the energy given off when a substance freezes.

6. When using heats of formation, Hf, what is the value for any element in its standard state?

7. Zero

8. On a graph of the energy change within a chemical reaction, what is the relationship between the reactants and products of an endothermic reaction? Draw a graph to help illustrate your point.

9. Energy for the reactants are lower than the energy of the products

10. When looking at a thermochemical reaction, where is the heat added into the equation for an exothermic reaction?

11. To the products

12. When acetic acid is fully combusted 871.7 kJ of heat is released. How many liters of CO2 gas is produced when 2512 kJ of heat is released at STP? H = -871.7 kJ HC2H3O2+ 2O2 --> 2CO2 + 2H2O

14. Starting reaction:2H2 (g) + O2 (g) -> 2H2O (g) ΔH = -484 kJ Calculate the ΔH for the new reaction: 6H2 (g) + 3O2 (g) -> 6H2O (g) ΔH = ???

15. -1452 kJ

16. An unknown object is dropped into a CCC containing 75.5 mL of water. The water's temperature rises from 15.3oC to 33.2oC. Calculate the qobject.

18. Find the ΔH for the reaction below, given the following reactions and subsequent ΔH values: 2CO2 + H2O → C 2H2 + 5/2O2 C2H2 + 2H2 → C2H6ΔH =-94.5 kJ H2O → H2 + 1/2O2ΔH =71.2 kJ C2H6 + 7/2O2 → 2CO2 + 3H2OΔH =-283 kJ

19. C2H6 C2H2 + 2H2ΔH =+94.5 kJ 2H2 + O2 2H2O ΔH =-142.4 kJ 2CO2 + 3H2O  C2H6 + 7/2O2ΔH =+283 kJ • 235 kJ

20. When potassium chloride reacts with oxygen under the right conditions, potassium chlorate is formed. Calculate the H for the reaction using the heats of formation on page 1041. 2 KCl (s)+ 3 O2 (g)2KClO3 (s)

21. 2 KCl (s) + 3 O2 (g) 2KClO3 (s) Hrxn = Hf(products) - Hf(reactants) Hrxn = [2(-391.2 kJ/mol)] – [2(-435.9 kJ/mol)] Hrxn = -782.4 kJ/mol– (-871.8 kJ/mol) Hrxn = 89.4 kJ/mol

22. Write the reaction for the standard enthalpy formation of calcium carbonate.

23. ½Ca(s) + ½C (s) + 3/2O2 (g) CaCO3 (s)