{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

rvw3 - Exam 3 Review Sheet Exam 3 covers Chapter 6.3-end Ch...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Exam 3 Review Sheet Exam 3 covers Chapter 6.3-end Ch. 6, Ch 7, and Ch 8 – 8.4 (Based on our expected coverage.) This review sheet is meant to be used after you have worked the problems suggested in your textbook and worked the old exam available at http://www-class.unl.edu/chem109/tests.htm Do NOT just study old exams! Suggested ways to work this review sheet: Review the problems given from previous exams. If you find difficulty working those, work similar problems that have answers given. Alternatively, you can work all problems on the review sheet. **Advice: Before putting things in your N-space, decide everything you want to put into it, trace the space onto another sheet of paper and write everything in – then you will know how large or small to write. All N-space suggestions are equations or diagrams we have discussed and I would think are useful. You may feel there are fewer or more items needed for your own sheet. Chapter 6.3-end: Calorimetry and Enthalpy (Thermodynamics) N-Space Suggestions: q = mc T ; q = nC T ; q cal = C cal T ; (know what each symbol stands for!) –q sys = q sur ; H f requires one mole product, reactants are elements in natural state, at STP ; H rxn = Σ(∆ H products ) - Σ(∆ H reactants ) Problems: 1. I gave you 4 pages of calorimetry and enthalpy questions in a handout posted on blackboard. Do those! 2. Using Hess’s Law and these three reactions (x, y, and z), (x) C (graphite) + O 2(g) CO 2(g) H x = -395.5 kJ (y) S (rhombic) + O 2(g) SO 2(g) H y = -296.1 kJ (z) CS 2(l) + 3O 2(g) CO 2(g) + 2 SO 2(g) H z = -1072.0 kJ determine the enthalpy change for the reaction, C (graphite) + 2S (rhombic) CS 2(l). (84.3 kJ) 3. Circle any of the following chemical equations for which H 0 rxn = H 0 f . a) ½ C (graphite) + S (rhombic) ½ CS 2(l). b) C (graphite) + O 2(g) CO 2(g)
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
c) 2CaCO 3(s) 2Ca (s) + 3O 2(g) + 2C (s) d) 4NH 3(g) + 7O 2(g) 4NO 2(g) + 6H 2 O (g) e) CaCO 3(s) Ca (s) + 3/2 O 2(g) + C (s) 4. Calculate the enthalpy change for this reaction using standard enthalpies of formation. 4 NH 3(g) + 7 O 2(g) 4 NO 2(g) + 6 H 2 O (g) (-1130.2 kJ) 5. Next to each of the following reactions, write (a), (b), or (c). (a)= Work done by system on surroundings. (b)= Work done by surroundings on system. (c) = No work is done. (i) CaCO 3(s) CaO (s) + O 2(g) (ii) CS 2(l) + 3O 2(g) CO 2(g) + 2 SO 2(g) (iii) C (solid, graphite) + O 2(g) CO 2(g) (iv) H 2 O (g) H 2 O (l) (v) CO 2(s) CO 2(g) (i. a; ii. c; iii. c; iv. b ; v. a) 6. Interesting Questions Concerning Heat from http://hyperphysics.phy- astr.gsu.edu/hbase/thermo/heatques.html#c1 Think about them, then visit to find out answers. How is it that you can have both water and ice at 0 C and both water and steam at 100 C? A lot of energy goes into these phase transitions. Why doesn't it change the temperature? If you have steel and wood at 0 C, which feels colder? If you have steel and wood at 100 C, which feels hotter?
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern