Why is it impossible to measure an excimer absorption spectrum, even for highly concentrated solutions? Illustrate your answer with an energy diagram

Consider these liquids.

Dishwashing detergent: 1.03 density g/mL

Maple syrup: 1.37 density g/mL

Vegetable oil: 0.91 g/mL

a. if you pour equal volumes of these three liquids into a 250 milliliter graduated cylinder, in what order will you add the liquids to create three separate layers? Explain your reasoning.

b. If a liquid were poured into the cylinder and it formed the layer that was on the bottom of the other three layers, what can you tell about one of the properties of this liquid?

c. what would happen if a volume of water equal to the other liquids report into the cylinder and part A and then the contents were mixed vigorously? Please explain.

Please explain the science behind municipal water treatment including chlorination and alternatives to chlorination (UV radiation, etc).

1.) A voltaic cell utilizes the following reaction and operates at 298 K:
3Ce4+(aq)+Cr(s)→3Ce3+(aq)+Cr3+(aq).

What is the emf of the cell when [Ce4+]= 1.3×10−2 M ,[Ce3+]= 2.6 M , and [Cr3+]= 1.7 M ?

2.)Calculate the equilibrium constant K at 298 K:

Aqueous iodide ion is oxidized to I2(s) by Hg22+(aq)

In acidic solution, copper (I) ion is oxidized to copper (II) ion by nitrate ion

In basic solution, Cr(OH)3(s) is oxidized to CrO2−4(aq) by ClO−(aq)

Part A

As a technician in a large pharmaceutical research firm, you need to produce 150. mL of a potassium dihydrogen phosphate buffer solution of pH = 7.00. The pKa of H2PO4− is 7.21. You have the following supplies: 2.00 L of 1.00 M KH2PO4 stock solution, 1.50 L of 1.00 M K2HPO4 stock solution, and a carboy of pure distilled H2O. How much 1.00 M KH2PO4 will you need to make this solution? (Assume additive volumes.) Express your answer to three significant digits with the appropriate units.

Part B

If the normal physiological concentration of HCO3− is 24 mM, what is the pH of blood if PCO2 drops to 24.0 mmHg ?

Express your answer numerically using two decimal places.

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.