the Log P value is 4.51 explain briefly how this value is determined and give an example of its significance related to the environmental behavior of the chemical?

3. What drug groups are in LCMSMS method? Why is it important to analyze these drug groups in urines form patients of a pain management clinic?

A Zn-Cu battery is constructed as follows at 25^oC

Zn_(s) | Zn⁺²_(aq) (0.20 M) || Cu⁺²_(aq) (2.5 M) | Cu_(s)

The mass of each electrode is 200.0 gram and the volume of the electrolytes is 1.0 L

a) calculate the cell potential of the cell

b) calculate the mass of each electrode after 10.0 amp. of current has flowed for 10.0 hour Remember, the anode loses mass because of the oxidation reaction while the cathode gains mass due to the reduction process.

c) how long can this battery deliver a current of 10.0 amp before it goes dead?

Question 2-17

You want to maintain a pH = 7.0 for an enzyme-catalyzed reaction that will produce hydrogen ions along with the desired product. At equal concentrations, which weak acid, if any, will serve as the better buffer for the reaction: Acid A, with pKa = 6.5 or Acid B, with pKa = 7.5?

a. Acid A

b. Water is as good as either of the acid available

c. Acid B

a) Calculate the volume of 0.5M NaOH that will be required to titrate a 0.15g sample of aspirin. b) If the student reached the end point of the titration 0.76 mL prior to the calculated value in (part a). What was the purity of the sample? The student required 0.40mL more NaOH than she calculated she would need in (part a). Explain how this might happen.

Calculate the pH of a 0.340M NaO₂CCO₂H solution. pK_a1 = 1.250 and pK_a2 = 4.266. Apparently the answer is 2.79 but can someone explain this?

a. -0.029

b. 3.38

c. 2.79

d. 4.89

e. 2.37

A) Arrange the following in order of increasing energy:

a) 9.9 x 10¹⁴ Hz

b) 255 nm

c) 410 kJ/mol

B) A metal has a work function of 385 kJ/mol. Which of the above photons could eject an electron from this metal? Why?

1a.Explain the specific functions of an internal standard in i) HPLC ii) AES

b. Define the following terms in atomic spectroscopy. Give two examples for each of them.
i) releasing agents
ii) protective agents
iii) ionization suppressors

An alloy contains 97% by mass aluminium and 3% by mass copper.

8. Using 100 kg of material as the starting point, what proportion of the atoms are copper?

What is the difference between the Normal Hydrogen Electrode (NHE) and the Reversible Hydrogen Electrode (RHE)?

- Also, if a redox happens at the NHE of 0.2 V, please calculate the potential for the RHE at pH = 1.

The reaction below has an equilibrium constant K p =2.2× 10 6 at 298 K. 2 COF 2 (g)⇌ CO 2 (g)+ CF 4 (g) Part A Calculate K p for the reaction below. COF 2 (g)⇌ 1 2 CO 2 (g)+ 1 2 CF 4 (g) Part B Calculate K p for the reaction below. 2 3 COF 2 (g)⇌ 1 3 CO 2 (g)+ 1 3 CF 4 (g) Part C Calculate K p for the reaction below. 2 CO 2 (g)+2 CF 4 (g)⇌4 COF 2 (g)

You are asked to prepare 500. mL of a 0.300 M acetate buffer at pH 4.90 using only pure acetic acid (MW=60.05 g/mol, pKa=4.76), 3.00 M NaOH, and water. Answer the following questions regarding the preparation of the buffer.

What volume of 3.00 M NaOH must you add to the acetic acid to achieve a buffer with a pH of 4.90 at a final volume of 500 mL? (Ignore activity coefficients.)

Copper salts – Assume that, in this question, the cation-to-anion size ratio should be in the 0.25 – 1 range and that all compounds adopt cubic cells. a) The chloride atoms are in tetrahedral holes in copper(I) chloride (Copper has +1 charge). Draw the unit cell of copper(I) chloride. b) Propose a unit cell for copper(II) chloride (Copper has +2 charge) and draw. c) Determine the coordination numbers for copper and chloride atoms in copper(II) chloride. d) Compare the densities of copper(I) chloride and copper(II) chloride. e) Compare the lattice parameters for copper(I) chloride and copper(II) chloride. f) Propose a unit cell for copper(I) sulfide (Copper has +1 charge) and draw. g) Determine the coordination numbers for copper and sulfide atoms in copper(I) sulfide.