Question
I need help with the notebook calculations section.
.This reaction should be performed in a fume hood and requires adherence to standard . Refluxing mixtures of acetonitrile and water can bump without adequate stirring. Heating . Morpholine is toxic and a skin, eye and respiratory irritant. This reagent should be precautions including the use of safety goggles and gloves. should be monitored carefully to avoid superheating of acetonitrile. handled in fume hoods and use of gloves to avoid skin contact. Eye protection! Lighting Up Protons Page 2 Paraformaldehyde is a carcinogen. Manipulations with this chemical should be carried out with gloves to avoid skin contact. All acetonitrile and ethanol must be collected and disposed of appropriately as flammable organic solvents waste. . . Notebook Calculations: a. Calculate the mass (mg) of morpholine, paraformaldchyde and dichlorofluorescein needed. b. Calculate the theoretical yield of product (mg and mmol). Reaction Procedure: Place morpholine ( g, 4.00 mmol), paraformaldehyde ( g. 3.74 mmol) and 10 mL of acetonitrile in a 50-mL round-bottom flask containing a magnetic stir bar. Attach a reflux condenser and heat the reaction mixture at reflux with stirring for 30 min. Dissolve 2',7 dichlorofluorescein g. 1.25 mmol) in 15 mL of acetonitrile/water (1:1) and add the resulting solution to the reaction mixture. Continue heating the reaction mixture at reflux for at least 2 h. Allow the reaction mixture to cool slightly and carefully place it in your lab drawer until the next lab period. Dilute the reaction with 20 mL of H20 and place the flask in an ice bath to induce precipitation. Collect the product by vacuum filtration. Suspend the crude product in boiling hot ethanol. Collect the purified product by vacuum filtration, and wash the crystals with ice cold water. Obtain a melting point and IR spectrum of the product. Fluorescence Assay Add 5 mL each of the unknown solutions A, B and C into labeled small test tubes (2 test tubes of each unknown solution). The solutions have a pH of 5, 7 or 12. Prepare 10 mL of a 1 mM solution of MorphFl and 10 mL of a solution mM of 2",7-dichlorofluorescein in dimethylsulfoxide (DMSO). Place a drop of the DMSO stock solution into each of the unknown solutions so that there are test tubes containing each unknown solution and either MorphFl or 2',7-dichlorofluorescein. Obtain both UV-Vis and Fluorescence spectra of both solutions. Determine what unknown corresponds to what ph.
Explanation / Answer
As per the question we need to know the amount of all the given compounds
Remember: Mole = Mass of substance / Molecular weight
Or mass = Moles X molecular weight
a) grams of morphine = Moles X molecular weight of morphine = Moles X 285.34
Grams = 4 X 10^-3 X 285.34 = 1.141 grams
b) We take molecular weight of paraformaldehyde as monomeric unit = 30.3
Mass = Moles X molecular weight = 30.3 X 3.74 X 10^-3 = 0.113 grams
c) Mass of Dichlorofluorescein = Moles X molecular weight = 1.25 X 10^-3 X 401.20 = 0.501 grams
For the yield of product we need the reaction stoichiometry and product