In the fed state, glucose is directed towards certain metabolic pathways in the liver
(many of which are regulated at least in part by insulin). Indicate the potential metabolic fates
of glucose in the fed condition and indicate how glucose enters the pathway (e.g., for entry into
the Pentose Phosphate Pathway, glucose must be converted to Glucose-6-Phosphate by
Glucokinase).

If the Ka of a monoprotic weak acid is 7.0 × 10^-6, what is the pH of a 0.24 M solution of this acid?

The solubility of Cu2CrO4 in water at 25 °C is 1 x 10–4 mol L–1. The solubility product constant at this temperature is

Part A. Calculate the pH of a buffer solution that is 0.250 M in HCN and 0.168 M in KCN. For HCN, Ka = 4.9×10⁻¹⁰ (pKa = 9.31).

Part B. Calculate the pH of a buffer solution that is 0.240 M in HC2H3O2 and 0.190 M in NaC2H3O2. (Ka for HC2H3O2 is 1.8×10−5.)

Part C. Consider a buffer solution that is 0.50 M in NH3 and 0.20 M in NH4Cl. For ammonia, pKb=4.75. Calculate the pH of 1.0 L of the original buffer, upon addition of 0.150 mol of solid NaOH.

Part D. A 1.0-L buffer solution contains 0.100 mol HC2H3O2 and 0.100 mol NaC2H3O2. The value of Ka for HC2H3O2 is 1.8×10−5. Calculate the pH of the solution, upon addition of 0.055 mol of NaOH to the original buffer.

Fresh feed containing 55 wt% A and 45 wt% B flowing at 100kg/h enters a separation system that removes a portion of pure component A only, as a bottom product. The top product stream (tops) of the separator unit contains 10 wt% of componenet A and the balance is B. A small part of the tops stream is recycled and mixed with the fresh feed stream- the remainder of the tops stream is purged. The separtor is designed to removed exactly two-thirds of component A that is fed into it. Determine the recycle ration (that is the ratio of the flow of the recycle stream to the flow of the fresh feed stream).

A beaker with 1.80×102 mL of an acetic acid buffer with a pH of 5.000 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.100 M. A student adds 8.00 mL of a 0.450 M HCl solution to the beaker. How much will the pH change? The pKa of acetic acid is 4.740.

Answer the following for the reaction: Pb(NO3)2(aq)+2KCl(aq)→PbCl2(s)+2KNO3(aq)

How many milliliters of a 2.05 M Pb(NO3)2 solution will react with 40.5 mL of a 1.45 M KCl solution? Please show work!

Thanks

7. Discuss the primary issues associated with protein folding.

1. You are working with chymotrypsin, and you mutate the Ser-195 to Alanine and see a 106–fold decrease in activity. You also, separately, mutate His-57 to Alanine and see a similar decrease in activity.

a. Draw the original, whole chymotrypsin mechanism concerning the wild type catalytic triad. Make sure to label the the N and C terminal ends of the peptide being cleaved, as well as the new N and C termini formed.

b. Draw the catalytic triad with the S195A mutation, and then the catalytic triad with the H57A mutation, instead. Explain which interactions are lost, compared to the original catalytic triad. A new student in your lab creates a chymotrypsin double mutant, with both Ser and His being mutated to Ala at the same time. The student says that since the activity, individually, decreases 106 fold, together, it should decrease activity 1012-fold.

c. Is this conclusion correct? Why or why not?

Calculate the pH and concentrations of CH3NH2 and CH3NH3 in a 0.0323 M methylamine (CH3NH2) solution. The Kb of CH3NH2 = 4.47 × 10-4.

Calorimetry and Standard Enthaply question: Manganese reacts with sulfuric acid to produce manganese (II) sulfate and hydrogen gas.

Mn(s) + H2SO4(aq) ---> MnSO4(aq) + H2(g) When 1.230g of Mn is combined with enough sulfuric acid to make 100.0mL of solution in a Thermo bottle calorimeter (heat capacity is 58.9 J/°C), all of the Mn reacts raising the temperature of the solution from 24.1°C to 34.5°C. (Assume that the specific heat capacity of the solution is 4.18 J/g°C and the density is 1.02g/mL.)

A) Is this reaction exothermic?

B) What is the heat (q) in Kg for the reaction according to the process described above?

C) Find ∆H°rxn for the chemical reaction as written above.

D) Consider the above given reaction. How many grams of manganese are needed if 895.0kJ of heat are released?

How long will it take 10.0 ml of Ne gas to effuse through aporous barrier if it has been observed that 125 mins are required for 10.0 ml of AR gas to effuse through the same barrier?

Calculate the concentration of all species in a 0.14 M KF solution.

[K+], [F−], [HF], [OH−], [H3O+]

please give each value clearly

A) Suppose you dump a bucket of water (5.00kg at 15.0C) outside on a cold night where T = -10.0C, and the water spreads out over an area so large that the temperature of the ground remains at -10.0C, acting like an ideal “cold reservoir.” Calculate the entropy change of the water in going from 15.0C to -10.0C, and calculate the entropy change of the environment, absorbing heat while staying (approximately) at -10.0C. This problem requires you to use TWO equations for entropy change – of a substance changing temperature and for a substance with Q in or out but at constant T. I got somewhat less than 8000J/K for the “environment’s” ∆S.

B) Use your answers to part A to solve for the total entropy change of the UNIVERSE in that process (ie, add the entropy changes of all the parts, confirming that the entropy change of the UNIVERSE is positive.)

C) Some people uncomfortable with the idea of evolution try to argue against it because, they say, it says that more “ordered” organisms evolve from less ordered organisms. Since entropy is a measure of “disorder,” this can’t happen. Now suppose for a moment that if you really did calculate the entropy of a bunch of “biomass” of 1 billion years ago, full of primitive organisms and a few inorganic compounds, and the equivalent “biomass” of a few people, and you found that the entropy WAS lower for the people, indicating that, yes indeed, the more complex organisms DO have lower entropy than the equivalent “primitive stuff” of which they were made. Why does this STILL not violate the second law of thermodynamics? (Hint: is part B fundamentally different from part A of this exercise, or are they fundamentally the same?)

1) Calculate of pH of each of the following strong acid solutions: (a) 8.5 x 10^-3 M HBr, (b) 1.52 g of HNO3 in 575 mL of solution, (c) 5.00 mL of 0.250 M HClO4 diluted to 50.0 mL, (d) a solution formed by mixing 10.0 mL of 0.100 M HBr with 20.0 mL of 0.200 M HCl.

2) Calculate [OH-] and pH for (a) 1.5 x 10^-3 M Sr(OH)2, (b) 2.250 g of LiOH in 250.0 mL of solution, (c) 1.00 mL of 0.175 M NaOH diluted to 2.00 L, (d) a solution formed by adding 5.00 mL of 0.105 M KOH to 15.0 mL of 9.5 x 10^-2 M Ca(OH)2

3) Latic acid (CH3CH(OH)COOH) has one acidic hydrogen. A 0.10 M solution of lactic acid has a pH of 2.44. Calculate Ka.

4) A 0.100 M solution of chloroacetic acid (ClCH2COOH) is 11.0% ionized. Using this information, calculate [ClCH2COO-], [H+], [ClCH2COOH], and Ka for chloroancetic acid.