1. Home
  2. Flashcards
  3. Preview

Chem 481 Test 4

  1. How does the energy of the universe respond to an isolated reaction?
    • The Energy of the Universe is constant. It comprises the the systemic change in energy and the surrounding change in energy.
    • Image Upload 2
  2. Describe the Entropy of the universe:
    • The entropy (disorder) of the universe is increasing. This can also be said that:
    • Image Upload 4
  3. Describe the relation between The change in energy and the change in disorder:
    Image Upload 6
  4. What can the ideal Gibbs free energy for a reaction be defined as?
    Image Upload 8
  5. What is the difference between these two symbols:
    Image Upload 10
    Image Upload 12
    • Image Upload 14 is the change in energy under ideal conditions.
    • Image Upload 16 is the change in energy under real conditions.
  6. What are standard or ideal conditions to calculate the change in energy?
    • 298K
    • [1M]
    • pH=7.0
  7. How is the real change in energy calculated from the ideal change in energy?
    • Image Upload 18
    • Where Q is the mass action ratio of [P][R]
  8. What is the mass action ratio?
    It is equal to Q=[products]/[reactants]
  9. What is lnQ when P=R=1M?
    What is the real change in energy at these conditions?
    Image Upload 20

    • Image Upload 22
    • Image Upload 24
  10. What is the Image Upload 26 
    • It is the phosphorylation Potential.
    • Net Exergonic.
    • Ideal is -30.5 kJ/mol
  11. Describe the change in energy when bonds break:
    Bonds breaking always requires energy, thus it is endergonic.
  12. Describe the change in energy when bonds form:
    When bonds are formed unstable participants enter into stable forms. Entering this more stable form allows them to have a lower energy state. This is always Exergonic.
  13. If:
    Image Upload 28 What is:
    Image Upload 30?
    Image Upload 32
  14. What is pyrophosphate?
    Image Upload 34
  15. Which would be more exergonic, the hydrolysis of ATP into ADP and phosphate, or into AMP and pyrophosphate?
    • ATP into AMP and Pyrophosphate.
    • Comparing the ideal delta G:
    • ADP+P:AMP+PP
    •   -30.5:-45.6
    •        2:3
  16. Generally will have more or less resonance forms make a product more exergonic?
    • More resonance=more stable.
    • more stable=lower delta G.
  17. does sulfur make strong or weak pi Bonds?
    weak pi bonds.
  18. What is the role and final change in energy for an adenylate kinase reaction?
    Image Upload 36
  19. Would ATP into ADP+P or GTP into GDP+P be more exergonic?
    They would be energetically identical because all NTP's are more or less energetically identical.
  20. What does phosphocreatine do?
    • It allows ADP to be turned into ATP in muscles.
    • Image Upload 38
  21. What are 2 ways of determining the oxidation states?
    • 1. Standard electron assigning (H+1, O-2)
    • 2. Determining the electron position based on each bond:
    • Image Upload 40
  22. How would the electrons be assigned for ethanol?Image Upload 42
    Image Upload 44
  23. What are the oxidation numbers for the atoms in ethanol?
    Image Upload 46
    • O (6-8)=-2
    • C1(4-5)=-1
    • C2(4-7)=-3
    • H1-6(1-0)*6=+6
    • Net=0
  24. What does a concerted reaction mean?
    That it happens all in 1 step
  25. What is Hydride?
    Is it a strong or weak leaving group?
    • H: Hydrogen with both electrons.
    • H-
    • Strong leaving group.
  26. What 4 things would indicate a REDOX reaction?
    • 1. Direct transfer of electrons
    • 2. Hydrogen atoms are transfered as H+ e- pairs.
    • 3. Hydride ions are transfered (NADH NAD+)
    • 4. Direct combination with O2
  27. What does NAD stand for?
    Nicotinamide Adenine Dinucleotide.
  28. Is nicotinamide a purene or a pyrimadine.
    • It is a special pyrimadine called a pyradine.
    • Image Upload 48
  29. What is the structural change between NAD+ and NADH?
    • the pyradine is reduced by Hydride at the 4 position. resulting in NADH and H+
    • Image Upload 50
  30. What is the structural difference between NAD+ and NADP+?
    • Hydroxyl is eserified with phosphate.
    • Image Upload 52
  31. What wavelength does Oxidized NAD+ absorb?
    260nm.
  32. What wavelength does Reduced NADH absorb?
    around 340 and also 260.
  33. What is E'o?
    Standard reduction potential.
  34. What is E?
    real reduction potential.
  35. What is the equation to give the real reduction potential?
    Image Upload 54
  36. how does the change in reduction potential relate to reduced reduction potential and the oxidized reduction potential?
    Image Upload 56
  37. How does the change in energy relate to the change in reduction potential?
    Image Upload 58
  38. How do you convert from C to K?
    • C+273=K
    • K-273=C
  39. What is the numerical value of R
    8.315
  40. What is the numerical value of F?
    96500
  41. What are two ways to regulate a pathway?
    • 1. Changing the number of the enzymes.
    • 2. Changing Enzyme activity.
  42. What process produces NADPH?
    The pentose phosphate pathway.
  43. What is the preparatory phase of glycolysis?
    • This refers to the first 5 steps.
    • 2 ATP are used.
    • 2 glyceraldehyde-3-phosphates are produced.
    • Has 2 "commitment steps"
  44. Describe the payoff phase of glycolysis:
    • This refers to the last 5 steps.
    • Everything happens x2.
    • Total: 4 ATP produced, 2 NADH, 2 pyruvate.
    • Involves only 1 irreversible step.
  45. What do the exact values of the delta G depend on?
    They depend on specific conditions, like concentration or heat in the system.
  46. What steps of glycolysis Involve large changes in the change in energy?
    • 1 Glucose+ATP->glucose-6-phophate+ADP
    • 3 Fructose-6-phosphate+ATP->fructose 1,6-bisphosphate+ADP
    • 10 Phosphophenolpyruvate+ADP->pyruvate+ATP
  47. What enzyme catalyses the first step in glycolysis?
    Hexokinase
  48. What enzyme catalyses the 3rd step in glycolysis?
    • Phosphofructokinase-1
    • (PFK-1)
  49. What enzyme catalyzes the 10th step in glycolysis?
    • Pyruvate Kinase.
    • Named for reverse reaction.
Author
ccraigr
ID
201809
Card Set
Chem 481 Test 4
Description
review questions based off of daily lectures in Chem 481. Starting with chapter 13.
Updated

  1. Home
  2. Flashcards
  3. Preview