Consider the titration of a 20.0 mL sample of 0.105 M HC₂H₃O₂ with 0.125 M NaOH.

Determine each quantity:

a. the initial pH

b. the volume of added base required ot reach equivalence point

c. the pH at 5.0 mL of added base

d. the pH at one-half of the equivalence point

e. the pH at the equivalence point

f. the pH after adding 5.0 mL of base beyond the equivalence point

Please add explanations!

You have been provided a mixture containing four amino acids (Glu, His, Pro and Lys) to be separated by ion-exchange chromatography using a Dowex 50 cation-exchange, prepared in a loading buffer at pH 2.0. The following solutions are made available:

• The amino acid mixture in 0.04M citrate buffer at pH 2.0.

• 0.04M citrate buffer, pH 4.5

• 0.04M citrate buffer, pH 8.0

• 0.04M citrate buffer, pH 10.5

  Is complete resolution of all amino acids achieved if the buffers are allowed to elute through the column sequentially from lowest to highest pH? Identify the order of elution and identify any amino acids that may come off the column together if complete resolution is not achieved. Support your response with an explanation.
  Assuming the amino acids in the mixture will elute from the column ONLY at a solution pH that is above their respective pI.

1. An anion-exchange resin can be used instead of the cation-exchange resin in this experiment to separate the three amino acids in the known mixture. What changes to experimental protocol are required to achieve complete resolution? Support your response with an explanation. (HINT: consider pH).

2. You have been provided a mixture containing four amino acids (Glu, His, Pro and Lys) to be separated by ion-exchange chromatography using a Dowex 50 cation-exchange, prepared in a loading buffer at pH 2.0. The following solutions are made available:

3. The amino acid mixture in 0.04M citrate buffer at pH 2.0.

4. 0.04M citrate buffer, pH 4.5

5. 0.04M citrate buffer, pH 8.0

6. 0.04M citrate buffer, pH 10.5

   Is complete resolution of all amino acids achieved if the buffers are allowed to elute through the column sequentially from lowest to highest pH? Identify the order of elution and identify any amino acids that may come off the column together if complete resolution is not achieved. Support your response with an explanation.
   Assuming the amino acids in the mixture will elute from the column ONLY at a solution pH that is above their respective pI.

A 1.159 g sample contains only vitamin C (C6H8O6) and sucralose (C12H19Cl3O8). When the sample is dissolved in water to a total volume of 34.0 mL, the osmotic pressure of the solution is 4.06 atm at 297 K. What is the mass percent of vitamin C and sucralose in the sample?

Comments: No Ionization of Vitamin C

I need to find the equivalence weight of a substance with a COOH group.

I weighed out 0.150 grams of the substance and dissolved it in 30 mL ethanol.

I titrated with 0.0999 M NaOH and used phenolptalein as an indicator.

The color completely shifted form clear to a purple-reddish at 9.8 mL 0.0999 M NaOH added.

I know that the substance only has one COOH group.

The question is how i find the equivalence weight?

Gel filtration chromatography can also be used to determine the molecular mass of proteins. What additional information might this technique provide as compared to SDS-PAGE or ESI-MS (under standard conditions) Please Explain in depth.

Today one U.S. farmer produces enough to feed: a. 100 people b. 20 people c. 5 people d. 1000 people

How would the 3p orbitals split in an octahedral field? Briefly justify your answer.

Hi I am working on my chemistry homework about acids and bases and I am confused on this question from a lab. We used grape juice and cranberry juice and we had to put HCl and NaOH in the test tube full of juice.

1. Referring back to procedure 1 of the experiment, which of the two juices is more useful as a general pH indicator and why? I think it is grape juice but I just don't know what to back my answer with. I appreciate the help!

Imagine that you are in chemistry lab and need to make 1.00L of a solution with a pH of 2.40.

You have in front of you

100 mL of 6.00

The motor symptoms of Parkinson's disease

1) If 22.0 mL of 2.3 M C₂H₅NH₂ are titrated with 0.9 M HCl, what is the pH at 13.1 mL?

2) If 25.1 mL of 2.2 M CH₃COOH are titrated with 0.9 M NaOH, what is the pH at 14.9 mL?

3) Exactly 47.0 mL of 0.2 M HNO₂ are titrated with a 0.2 M NaOH solution. What is the pH at the equivalence point ?

Say you are provided two samples containing an unknown concentration of calcium. One sample is a liquid and one sample is a solid (ie. calcium tablet). What analytical technique would be most efficient for chemical analysis and why? Take into consideration LOD, convenience, precision, accuracy, etc.

Gold is plated from a solution of Au³⁺ using a constant current of 4.86 A for 352 minutes.Calculate the grams of gold plated out of solution.

7. Chemical reactions are reversible, however enzymes can catalyze a reaction reversibly or irreversibly. Document each of these characteristics through graphic examples