I am doing a lab on extracting caffeine from soda using methylene chloride. What is the...
I am doing a lab on extracting caffeine from soda using methylene chloride. What is the main reaction that occurs?
*caffeine acts as a base and forms an acid with a PKa of 3.6 when protonated. NaOH is added before methylene chloride to make the pH ~8.
Homework Answers
The basic character of caffeine is because of the presence of lone pair of electrons on N - atom.
The main concept behind the extraction process is as follows:
NaOH is added before extraction with organic solvent inorder to make caffeine into neutral form (more soluble in non-polar solvents) rather than in ionic form(more soluble in water).
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I am doing a lab on extracting caffeine from soda using
methylene chloride. What is the...
Can you please check my work? I am having difficulty in differentiating my answers from pH>pKa...
Can you please check my work? I am having difficulty in
differentiating my answers from pH>pKa to pH<pKa. I do not
understand how acids and bases would be different among each other
in relation to pH and pKa. Guidance would be greatly appreciated.
Thank you.
D Question 5 8 pts pKa and pH pKa pH when the concentration of the protonated and deprotonated forms are the same. At a pH below the pKa, which form of a base will be...
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I'm doing a titration lab tomorrow and I am not sure what the formulas are to...
I'm doing a titration lab tomorrow and I am not sure what the
formulas are to calculate the moles of NaOH, the moles of
HCl, and the molarity of HCl.
The objective of this laboratory is to determine the molarity of
a hydrochloric acid solution using a known concentration of sodium
hydroxide as the titrant.
volume of HCl in flask: 25.00 mL
the net ionic equation for the reaction is:
H+(aq) + OH-(aq) --> H2O(l)
I don't have the data...
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I am most concerned with number 8 7. Identify the conjugate acid: NH3(ag) + HO(aq) =NH4*(ag)...
I am most concerned with number 8
7. Identify the conjugate acid: NH3(ag) + HO(aq) =NH4*(ag) OH (ag) a. NH3 b. NH4 с. НаО d. OН 8. A 50.0mL 0.100M weak acid is titrated with 0.100M NaOH and has K=1.6x10-5. Which of the following is true given the volume of N2OH added? (Hint: 25mL of N2OH added would be 2 of the equivalence point and 50mL of N2OH added would be the equivalence point) a. At 25.0mL added, pH=4.80, and...
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in FRIEDEL-CRAFTS ACYLATION AND COLUMN CHROMATOGRAPHY lab
(2 pts) Amount of acetyl chloride used ____4______(drops) (each
drop is 0.01 mL) _____2______(equivalents) Based on the amount of
ferrocene you began the Friedel-Crafts reaction with, determine the
percent yield of acetylferrocene, diacetylferrocene, and the
percent recovery of unreacted ferrocene (show work)
react by 0.100 g of ferrocene at beginning
got 0 g of ferrocene, 0.012g of diacetylferrocene , 0.017g of
acetylferrocene
REACTION PROCEDURE: To a 5 mL conical vial, add a spin...
Please here is my lab questions for titration of weak acid. The questions are very short....
Please here is my lab questions for titration of weak acid. The
questions are very short. You have to determine the answers by just
looking at the graph based on the data points. Please give me the
answers of all of them. I would really appreciate. Please calculate
the molar mass question #7 as well. It will be of great help to
me.
Mass of the unknown acid: 0.2grams
Concentration of NaOH = 0.0500M
Formuld Bal pH of weak acid...
Can you please check my work? I am having difficulty in
differentiating my answers from pH>pKa to pH<pKa. I do not
understand how acids and bases would be different among each other
in relation to pH and pKa. Guidance would be greatly appreciated.
Thank you.
D Question 5 8 pts pKa and pH pKa pH when the concentration of the protonated and deprotonated forms are the same. At a pH below the pKa, which form of a base will be...
I'm doing a titration lab tomorrow and I am not sure what the
formulas are to calculate the moles of NaOH, the moles of
HCl, and the molarity of HCl.
The objective of this laboratory is to determine the molarity of
a hydrochloric acid solution using a known concentration of sodium
hydroxide as the titrant.
volume of HCl in flask: 25.00 mL
the net ionic equation for the reaction is:
H+(aq) + OH-(aq) --> H2O(l)
I don't have the data...
I am most concerned with number 8
7. Identify the conjugate acid: NH3(ag) + HO(aq) =NH4*(ag) OH (ag) a. NH3 b. NH4 с. НаО d. OН 8. A 50.0mL 0.100M weak acid is titrated with 0.100M NaOH and has K=1.6x10-5. Which of the following is true given the volume of N2OH added? (Hint: 25mL of N2OH added would be 2 of the equivalence point and 50mL of N2OH added would be the equivalence point) a. At 25.0mL added, pH=4.80, and...
in FRIEDEL-CRAFTS ACYLATION AND COLUMN CHROMATOGRAPHY lab
(2 pts) Amount of acetyl chloride used ____4______(drops) (each
drop is 0.01 mL) _____2______(equivalents) Based on the amount of
ferrocene you began the Friedel-Crafts reaction with, determine the
percent yield of acetylferrocene, diacetylferrocene, and the
percent recovery of unreacted ferrocene (show work)
react by 0.100 g of ferrocene at beginning
got 0 g of ferrocene, 0.012g of diacetylferrocene , 0.017g of
acetylferrocene
REACTION PROCEDURE: To a 5 mL conical vial, add a spin...
Please here is my lab questions for titration of weak acid. The
questions are very short. You have to determine the answers by just
looking at the graph based on the data points. Please give me the
answers of all of them. I would really appreciate. Please calculate
the molar mass question #7 as well. It will be of great help to
me.
Mass of the unknown acid: 0.2grams
Concentration of NaOH = 0.0500M
Formuld Bal pH of weak acid...
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