Assume that you have a solution of 0.1 M glucose 6-phosphate. To this solution, you add the enzyme Phosphoglucomutase, which catalyzes the following reaction:
The ΔG0’ for the reaction is +1.8 kcal mol-1. (a) Does the reaction proceed as written? If so, what are the final concentrations of glucose 6-phosphate and glucose 1-phosphate?
In: Chemistry
Post-‐Lab to Accompany the Grignard Synthesis of Triphenylmethanol You were instructed to add the bromobenzene in increments during the Grignard preparation to prevent an unwanted side reaction. What would the product of that reaction be (show structure also)? How was it removed during work-‐up from the triphenylmethanol product?
In: Chemistry
1. A portion of NMR spectrum of 4-tert-butylcyclohexanol is shown below, along with a peak list of chemical shifts, multiplicities, and numbers of protons (from integration). Note: the alcohol O-H proton is NOT observed in this NMR spectrum.
a) The spectrum is consistent with a single isomer of 4-tert-butylcyclohexanol. Which one is it, cis or trans?
This spectrum is consistent with one isomer, the cis-4-butylcyclohexanol isomer.
a. Copy into your lab report the picture shown below the spectrum. Circle the structure of the correct isomer identified in (a).
http://www.chemicalbook.com/SpectrumEN_937-05-3_1HNMR.htm image is located on this url it wouldnt let me paste. Same image used for part b,
b. Within the circled structure, circle the most important proton or protons that informed your answer to part (a).
c. What peak or peaks in the spectrum peak list correspond to the circled proton or protons in part (c)?
e) In this molecule, what conformational relationship between two coupled protons determines their coupling constant to each other (J values)?
f) For the selected peak(s) in (d), explain the multiplicity. Be as specific as possible by referring to the labeled protons in your circled structure and highlighting relevant coupling constants.
|
1H NMR spectrum peak list, ppm (multiplicity, number of protons) |
|
4.03 (pentet, 1 H) |
|
1.84 (multiplet, 2 H) |
|
1.69 (singlet, 1 H) |
|
1.54 (multiplet, 2 H) |
|
1.45 (multiplet, 2 H) |
|
1.37 (multiplet, 2 H) |
|
0.99 (multiplet, 1 H) |
|
0.86 (singlet, 9H) |
In: Chemistry
This question is for a laboratory experiment titled "Determination of the Solubility Product Constant of Calcium Hydroxide" where a saturated solution of Ca(OH)2 in 0.02523M NaOH was titrated with HCl.
Part 2 Data - Saturated Solution of Ca(OH)2 in 0.02523M NaOH:
Volume of Ca(OH)2/NaOH aliquot: 25.00mL
Concentration of standard HCl: 0.1342M
Indicator Used: Bromothymol Blue
Average volume of HCl to reach end point: 10.26mL
a. Calculate the TOTAL [OH-] in the saturated solution of Ca(OH)2 in sodium hydroxide for the solution assigned (Ca(OH)2 in 0.02523M NaOH).
b. Calculate the [OH-] that comes from the dissolution of Ca(OH)2. The total [OH-] (calculated above) is the sum of the [OH-] from the NaOH and the [OH-] from Ca(OH)2.
c. Calculate the solubility of Ca(OH)2 in the NaOH solution (in mol/L).
d. Calculate the experimental Ksp of Ca(OH)2 for the saturated solution of Ca(OH)2 in NaOH.
Please explain steps/show equations! Thank you.
In: Chemistry
What are the IR and NMR spectral features of isoamyl acetate?
In: Chemistry
This question is for a laboratory experiment titled "Determination of the Solubility Product Constant of Calcium Hydroxide" where a saturated solution of Ca(OH)2 in water was titrated with HCl.
Part 1 Data - Saturated Solution of Ca(OH)2 in Water:
Volume of Ca(OH)2 aliquot: 25.00mL
Concentration of standard HCl: 0.1342M
Indicator Used: Bromothymol Blue
Average volume of HCl to reach end point: 7.71mL
a. Write a balanced, net ionic equation for the titration reaction. Use this equation to perform the subsequent calculations.
b. Calculate the [OH-] in the standard Ca(OH)2 solution (using the NET ionic equation).
c. Determine the experimental solubility of the Ca(OH)2 (in mol/L).
d. Determine the experimental Ksp of Ca(OH)2.
Please explain steps/show equations! Thank you.
In: Chemistry
Why should sodium bicarbonate solution be added slowly when synthesizing isoamyl acetate from isoamyl alcohol and glacial acetic acid? Write balanced equations for all reactions that take place during the neutralization (experiment involves isoamyl alcohol, glacial acetic acid, concentrated sulfuric acid, and 5% aqueous sodium bicarbonate).
In: Chemistry
The complex ion Cu(NH3)42 is formed in a solution made of 0.0400 M Cu(NO3)2 and 0.400 M NH3. What are the concentrations of Cu2 , NH3, and Cu(NH3)42 at equilibrium? The formation constant*, Kf, of Cu(NH3)42 is 1.70 × 1013.
In: Chemistry
Exercise 12.98 A gas has a Henry's law constant of 0.136 M/atm Part A How much water would be needed to completely dissolve 1.53 L of the gas at a pressure of 745 torr and a temperature of 23 ∘C?
In: Chemistry
The flask is charged with 0.80 g magnesium turnings, THF (45 mL), 4-bromo-N,N-dimethylaniline (5.0 g), and a small crystal of iodine. The mixture is warmed gently to reflux (set the hot plate to 200 °C) and maintained there for 30 min, during which time the original dark reddish-brown color changes to the typical “dirty dishwater” shade of the Grignard reagent. Check with your TA to ensure this has indeed happened.
The flask is cooled to room temperature (ice-water bath). Be sure to keep the solution dry. After 15 min. diethyl carbonate (0.49 g) in 5 mL of THF is added in one portion. The mixture is warmed to reflux for an additional 5 min, and then cooled again to room temperature (ice-water bath). Aqueous hydrochloric acid (15 mL of a 10% solution) is added
Write the theoretical yield of your product, crystal
violet
In: Chemistry
Compound A is a D-aldopentose that can be oxidized to an optically active aldaric acid B. On Kiliani-Fischer chain extension, A is converted into C andD; C can be oxidized to an optically inactive aldaric acid E, but D is oxidized to an optically active aldaric acid F.
What is the structure of compound C?
In: Chemistry
Air is a mixture of gases with the following mass percentage composition: 75.52% N2, 23.15% O2, 1.28% Ar, and 0.046% CO2.
A. What are the partial pressures of N2, O2, Ar, and CO2 when the total pressure is 1.100 atm?
B. Calculate the molar Gibbs energy of mixing of air at 25C assuming ideal gas behavior.
C. Determine the molar enthalpy of mixing and the molar entropy of mixing for air at 1.100 atm and 25C.
D. Is the mixing of pure gases to form air spontaneous? How does the total pressure affect spontaneity of gas mixing?
In: Chemistry
Imagine that you are in chemistry lab and need to make 1.00 Lof a solution with a pH of 2.80.
You have in front of you
100 mL of 7.00×10−2M HCl,
100 mL of 5.00×10−2M NaOH, and
plenty of distilled water.
You start to add HCl to a beaker of water when someone asks you a question. When you return to your dilution, you accidentally grab the wrong cylinder and add some NaOH. Once you realize your error, you assess the situation. You have 81.0 mL of HCland 90.0 mL of NaOH left in their original containers.
Assuming the final solution will be diluted to 1.00 L , how much more HCl should you add to achieve the desired pH?
In: Chemistry
1. Calculate the pH of a 0.339 M H2S. Calculate the [S2-] in the solution.
2. A titration is performed by adding 0.656 M KOH to 40 mL of 0.172 M HNO3:
b) Calculate the pH after the addition of 2.1, 5.25 and 9.49 mL of the base.(Show your work in detail for one of the volumes.)
e)Calculate the pH after adding 5.00 mL of KOH past the equivalence point
In: Chemistry