A biochemical engineer isolates a bacterial gene fragment and dissolves a 17.0 mg sample of the material in enough water to make 38.9 mL of solution. The osmotic pressure of the solution is 0.340 torr at 25

13. A 15.0 mL NaOH solution is required to neutralize 10.0 mL of 0.100 M H2SO4(aq) solution.   

     What is the concentration of NaOH solution used?  

2NaOH (aq) + H2SO4(aq) → Na2SO4(aq) + 2H2O(l)

Answer the reason why the cellulose is resistance to chemical attack. ( i.e. chemical structure bonding and so on )

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?