Post-Lab Question(s) 1. Write an experimental procedure describing how to use recrystallization technique to purify an unknown with two impurities with the following hypothetical properties: Cold Solvent 1 (20 °C) Insoluble Insoluble Hot Solvent 1 (95 °C) 6.0 g /100 mL 5.0 g/ 100 mL Cold Solvent 2 Hot Solvent 2 |Impurity A |Impurity B (20 °C) 0.80 g/ 100 mL Insoluble (95 °C) 4.8 g/ mL Insoluble Include needed amounts in your procedure.

Post-Lab Question(s) 1. Write an experimental procedure describing how to use recrystallization technique to purify an unknown with two impurities with the following hypothetical properties: Cold Solvent 1 (20 °C) Insoluble Insoluble Hot Solvent 1 (95 °C) 6.0 g /100 mL 5.0 g/ 100 mL Cold Solvent 2 Hot Solvent 2 |Impurity A |Impurity B (20 °C) 0.80 g/ 100 mL Insoluble (95 °C) 4.8 g/ mL Insoluble Include needed amounts in your procedure.

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter3: Statistical Tests With Excel

Section: Chapter Questions

Problem 6P

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Q1. Give three criteria for a good recrystallization solvent. Q2. You want to purify 10 grams of benzoic acid that has been contaminated with 0.2 g of salicylic acid. You are given the following data: Solubility in water at 20 °C Solubility at 100 °C (g/10 ml) Compound (g/10 ml) Benzoic Acid 0.029 0.680 Salicylic Acid 0.680 0.029 0.22 6.67 a) What volume of Boiling water is needed to dissolve the 10 g of benzoic acid? (show calculations) b) How much benzoic acid will crystallize after cooling to 20 °C (show calculations) c) Will any salicylic acid crystals form? Why or why not? (show calculations/ reason for answer) d) What is the maximum amount of benzoic acid that could be recovered in the first crop of this recrystallization? (Show calculations) e) How can you prove the purity and identity of the purified Benzoic acid?
2. You need to make 500mL of 7H9(+) media with 1X ADN and 30ug/ml. of the antibiotic kanamycin. Your stock solutions are 10X ADN and 30mg/mL of kanamycin. The solvent is distilled water. How much of cach component will you need to make the desired final solution?
chools.schoology.com/common-assessment-delivery/start/4573067641?action%3Donresume&submissionld%3547892539 150 140 130 120 110 100 NANO 90 80 70 60 NH C Ka Náci 50 40 30 20 KCIÓ, 10 Cez(so 10 20 30 40 50 60 70 80 90 100 Temperature (C) The compound with the least solubility at 50 °C is OKI O NANO3 O KNO3 O NH3 O NH&CI O KCI O NaCI O KCIO3 O Cex(SOa)a DELL & Grams of solute
Q/ Prepare 0.1 N and 0.1 M of 98% H₂SO4 in 250 ml. M.wt of H₂SO4 = 98 g/mol, and its Specific density (SP.gr.) = 1.09.
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1. You begin by measuring 10.00 mg of dye on a precise analytical balance and dissolve the dye in 1.000 1 of water having density 998.25 kg/m³. What is the concentration of the dye in mg/l, kg/m³, mg/kg, and ppm?
A 0.2422 g sample of a certain fruit was analyzed for the content of a certain pesticide. After a series of extraction steps, the final extract obtained was diluted to 10.00 mL, which was then subjected to chromatographic analysis. Four standard solutions of the pesticide were also prepared, processed, and analyzed in the same manner. The data obtained are shown in the table below. Solution Concentration (µg/mL) Peak Area Standard 1 0.01 234.2 Standard 2 0.05 1101.2 Standard 3 0.10 2300.1 Standard 4 0.20 4999.8 Sample ? 1654.3
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The melting temperature of pure acetylsalicylic acid is 135 degrees Celsius. Based on the results of the melting temperature test, what is the percent purity of your sample of aspirin? Part I Synthesis of Aspirin Mass of salicylic acid used (g) 2.029g Volume of acetic anhydride used (mL) 5ml Mass of acetic anhydride used (vol. × 1.08 g/mL) 5.4g Mass of aspirin synthesized (g) 3.256g Part II Melting Temperature Data Melting temperature (°C) 133°C Part III Salicylic Acid Standard Stock Solution Initial mass of salicylic acid (g) 0.210g Moles of salicylic acid (mol) 0.0147 mol Initial molarity of salicylic acid (M) 0.724 M Part III Beer’s Law Data for Salicylic Acid Standard Solutions Trial Concentration (M) Absorbance 1 10 0.301 2 7.5 0.219 3 5.0 0.163 4 2.5 0.074 Best-fit line equation for the salicylic acid standards Test of the Purity of the…