Bio Chemie opdrachten om je voor te bereiden op het tentamen PDF

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er zijn enkele opdrachten over biochemie om je kennis te toetsen en te kijken als je ready bent voor het tentamen...

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Geneeskunde Biochemie Algemeen Week 4A: Opdrachten 1. (a) What is meant by the term system in thermodynamics? (b) What do we call the part of the universe that is not part of the system? 2. State the first law of thermodynamics. 3. (a) Express the second law of thermodynamics in words. (b) If the entropy of the system increases during a reversible process, what can you say about the entropy change of the surroundings? (c) In a certain spontaneous process the system undergoes an entropy change, ΔS = 42 J/K. What can you conclude about ΔS surr? 4. How would each of the following changes affect the entropy of a system: (a) increase in temperature; (b) decrease in volume; (c) change of state from liquid to gas. 5. For a certain chemical reaction, ΔH° = +23.7 kJ and ΔS° = -85.5 J/K .(a) Is the reaction exothermic or endothermic? (b) Does the reaction lead to an increase or decrease in the randomness or disorder of the system? (c) Calculate ΔG° for the reaction at 298 K. (d) Is the reaction spontaneous at 298 K under standard conditions? 6. The specific heat of octane, C8H18(l), is 2.22 J/g-K. (a) How many J of heat are needed to raise the temperature of 80.0 g of octane from 10.0 °C to 25.0 °C? (b) Which will require more heat, increasing the temperature of 1 mole of C8H18(l) by a certain amount or increasing the temperature of 1 mole of H2O(l) by the same amount? (specific heat of water is 4.184 J/g-K) 7. Assuming that Coca Cola has the same specific heat as water (4.18 J/g.°C), calculate the amount of heat in kilojoules transferred when one can (about 350 g) is cooled from 25 °C to 3 °C.

Week 4B: Opdrachten 1. The following diagram shows the reaction profile of a reaction. Label the components indicated by the boxes.

2.

(a) What is meant by the term reaction rate? (b) Name three factors that can affect the rate of a chemical reaction. (c) Is the rate of disappearance of reactants always the same as the rate of appearance of products? Explain.

3. The decomposition reaction of N2O5 in carbon tetrachloride is 2 N2O5  4 NO2 + O2. The rate law is first order in N2O5. At 64°C the rate constant is 4.82 x 10-3 s-1 . (a) Write the rate law for the reaction. (b) What is the rate of reaction when [N2O5] = 0.0240 M? (c) What happens to the rate when the concentration of N2O5 is doubled to 0.0480 M? 4. The iodide ion reacts with hypochlorite ion (the active ingredient in chlorine bleaches) in the following way: OCl- + I-  OI- + Cl- . This rapid reaction gives the following rate data:

(a) Write the rate law for this reaction. (b) Calculate the rate constant with proper units. (c) Calculate the rate when [OCl-] = 2.0 x 10-3 M and [I-] = 5.0 x 10-4 M . 5. Write the expression for Kc for the following reactions: (a) 3 NO (g) ⇄ N2O (g) + NO2 (g) (b) Ni(CO)4 (g) ⇄ Ni (s) + 4 CO (g) (c) 2 Ag (s) + Zn2+ (aq) ⇄ 2 Ag+ (aq) + Zn (s) (d) 2 H2O (l) ⇄ 2 H+ (aq) + 2 OH- (aq) 6. The equilibrium constant for the reaction 2 NO (g) + Br2 (g) ⇄ 2 NOBr (g) is Kc = 1.3 x 10-2 at 1000 K. (a) At this temperature does the equilibrium favor NO and Br 2, or does it favor NOBr? (b) Calculate Kc for 2 NOBr (g) ⇄ 2 NO (g) + Br2 (g). 7. Methanol (CH3OH) is produced commercially by the catalyzed reaction of carbon monoxide and hydrogen: CO (g) + 2 H2 (g) ⇄ CH3OH (g). An equilibrium mixture in a 2.00-L vessel is found to contain 0.0406 mole CH3OH, 0.170 mole CO, and 0.302 mole H2 at 500 K. Calculate Kc at this temperature.

8. At 2000°C the equilibrium constant for the reaction 2 NO (g) ⇄ N2 (g) + O2 (g) is Kc = 2.4 x 103. If the initial concentration of NO is 0.175 M, what are the equilibrium concentrations of NO, N 2, and O2? 9. Ozone, O3, decomposes to molecular oxygen in the stratosphere according to the reaction 2 O 3 (g)  3 O2 (g). Would an increase in pressure favor the formation of ozone or of oxygen?...