The Synthesis of Aspirin - Revision history

Bes: /* The Synthesis of Aspirin: Week 1 of 2. */

2021-02-18T23:38:44Z

The Synthesis of Aspirin: Week 1 of 2.

Bes at 23:38, 18 February 2021

2021-02-18T23:38:31Z

Bes at 20:28, 11 March 2018

2018-03-11T20:28:13Z

Bes at 12:04, 9 February 2018

2018-02-09T12:04:01Z

Bes at 15:29, 28 April 2016

2016-04-28T15:29:57Z

Bes at 15:26, 28 April 2016

2016-04-28T15:26:02Z

Bes at 15:25, 28 April 2016

2016-04-28T15:25:21Z

Ptun: /* PROCEDURE: */

2016-04-22T15:55:56Z

PROCEDURE:

Ptun: /* PRELAB */

2016-04-22T15:55:14Z

PRELAB

Ptun at 15:54, 22 April 2016

2016-04-22T15:54:35Z

← Older revision		Revision as of 23:38, 18 February 2021
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	[[Media:Aspirin_1.pdf\|PDF]]		[[Media:Aspirin_1.pdf\|PDF]]
		+
	[[Media:1 aspirin syn.doc\|WORD Version]]		[[Media:1 aspirin syn.doc\|WORD Version]]

← Older revision		Revision as of 23:38, 18 February 2021
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	=='''The Synthesis of Aspirin: Week 1 of 2.'''==		=='''The Synthesis of Aspirin: Week 1 of 2.'''==

		+	[[Media:Aspirin_1.pdf\|PDF]]
	[[Media:1 aspirin syn.doc\|WORD Version]]		[[Media:1 aspirin syn.doc\|WORD Version]]

← Older revision		Revision as of 20:28, 11 March 2018
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		+	[[General_Chemistry_(Chem_140)\|...back to Chem 140]]
		+
	=='''The Synthesis of Aspirin: Week 1 of 2.'''==		=='''The Synthesis of Aspirin: Week 1 of 2.'''==

← Older revision		Revision as of 12:04, 9 February 2018
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	=='''The Synthesis of Aspirin: Week 1 of 2.'''==		=='''The Synthesis of Aspirin: Week 1 of 2.'''==
		+
		+	[[Media:1 aspirin syn.doc\|WORD Version]]

	===Prelab===		===Prelab===

← Older revision		Revision as of 15:29, 28 April 2016
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	TURN IN CARBON COPIES AT THE END OF EACH LAB PERIOD!		TURN IN CARBON COPIES AT THE END OF EACH LAB PERIOD!
		+
		+	=='''The Synthesis of Aspirin: Week 2 of 2.'''==
		+
		+	===Prelab===
		+
		+	===Purpose===
		+
		+	===Introduction===
		+
		+	===Procedure===

	===Instructors Notes===		===Instructors Notes===

← Older revision		Revision as of 15:26, 28 April 2016
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−	=='''~~Lab 4~~: ~~THE SYNTHESIS OF ASPIRIN: WEEK~~ 1 of 2.'''==	+	=='''The Synthesis of Aspirin: Week 1 of 2.'''==

	===Prelab===		===Prelab===

@@ Line 1: / Line 1: @@
 =='''Lab 4: THE SYNTHESIS OF ASPIRIN: WEEK 1 of 2.'''==
-===PRELAB===
+===Prelab===
 Complete the following Pre-lab assignment in your lab notebook prior to starting the lab.
 :1. Write out the synthesis reaction shown in Scheme 1 in your lab notebook.
@@ Line 13: / Line 13: @@
 '''
-===PURPOSE===
+===Purpose===
 The purpose of this lab activity is to explore the chemical reaction leading to the common product aspirin, also known as acetylsalicylic acid. During this first week, of this lab activity, you will synthesize aspirin. In next week’s lab you will determine the efficiency of your synthesis. During the synthesis you will also be exposed to the use of a suction filtration flask.
-===INTRODUCTION===
+===Introduction===
 As early as the time of Hippocrates (~400 BC), the compound salicylic acid (molecular mass = 138.12 g/mol) was recognized for its pain relieving properties.  Salicylic acid, however, is extremely irritating to the mouth and stomach.  In 1899, the Bayer Company introduced acetylsalicylic acid (molecular mass = 180.15 g/mol), a derivative of salicylic acid, which has the same pain relieving properties, but is less irritating to the stomach.  Acetylsalicylic acid is better known as aspirin. Naming of organic compounds can be confusing. Aspirin is also known by the chemical name 2-acetyloxybenzoic acid.
@@ Line 27: / Line 27: @@
 In this reaction, we say that salicylic acid is the limiting reagent (reactant) and that acetic anhydride is the excess reagent. The amount of acetylsalicylic acid that can be synthesized is a result of how much salicylic acid is added to the reaction mixture.
-===PROCEDURE:===
+===Procedure===
 :1. Prepare a hot water bath using a hot plate and 400 mL beaker that is half-filled with water.  While the water is heating to the boiling point, continue with step 2 in the procedure.
@@ Line 48: / Line 48: @@
 TURN IN CARBON COPIES AT THE END OF EACH LAB PERIOD!
-===Instructors Notes.===
+===Instructors Notes===
 Prelab demonstrations:

@@ Line 28: / Line 28: @@
 ===PROCEDURE:===
-. Prepare a hot water bath using a hot plate and 400 mL beaker that is half-filled with water.  While the water is heating to the boiling point, continue with step 2 in the procedure.
+:1. Prepare a hot water bath using a hot plate and 400 mL beaker that is half-filled with water.  While the water is heating to the boiling point, continue with step 2 in the procedure.
-. Using the top-loading balance, weigh about 2 grams of salicylic acid and place the solid in a DRY 125 ml Erlenmeyer flask. Record the actual mass of the acid to 2 decimal places in your lab notebook.
+:2. Using the top-loading balance, weigh about 2 grams of salicylic acid and place the solid in a DRY 125 ml Erlenmeyer flask. Record the actual mass of the acid to 2 decimal places in your lab notebook.
-. In a fume hood, add ~4 ml of acetic anhydride and 5 drops of concentrated sulfuric acid to the Erlenmeyer flask containing the salicylic acid.  CAUTION! Both acetic anhydride and sulfuric acid are strong irritants. Both need to be handled with care. Notify your instructor or TA to assist in cleaning up any spills. Gloves are available, but are not a substitute for good lab technique.
+:3. In a fume hood, add ~4 ml of acetic anhydride and 5 drops of concentrated sulfuric acid to the Erlenmeyer flask containing the salicylic acid.  CAUTION! Both acetic anhydride and sulfuric acid are strong irritants. Both need to be handled with care. Notify your instructor or TA to assist in cleaning up any spills. Gloves are available, but are not a substitute for good lab technique.
-. Return to your lab bench and swirl the contents of the flask for ~30 sec; all the material may not dissolve. Place the flask in the hot water bath for about ~20 minutes. While the sample is heating, continue to step 5.
+:4. Return to your lab bench and swirl the contents of the flask for ~30 sec; all the material may not dissolve. Place the flask in the hot water bath for about ~20 minutes. While the sample is heating, continue to step 5.
-. Prepare an ice water bath using a 600 ml beaker half-filled with ice and enough water to cover the ice. Place in the ice bath 5 test tubes, each containing ~10 mL of distilled water for later use.
+:5. Prepare an ice water bath using a 600 ml beaker half-filled with ice and enough water to cover the ice. Place in the ice bath 5 test tubes, each containing ~10 mL of distilled water for later use.
-. After the ~20 minutes of heating, remove the flask from the hot water bath and slowly and carefully add a total of 10 ml of cold distilled water to the flask in 1 ml increments with a transfer (plastic) pipette. CAUTION!  This reaction is intended to destroy unreacted acetic anhydride and can be violent!
+:6. After the ~20 minutes of heating, remove the flask from the hot water bath and slowly and carefully add a total of 10 ml of cold distilled water to the flask in 1 ml increments with a transfer (plastic) pipette. CAUTION!  This reaction is intended to destroy unreacted acetic anhydride and can be violent!
-. After 10 ml of the ice-cold water has been added, cool the flask and contents in the ice water bath for 10 minutes, occasionally stirring the contents with a glass rod. The acetylsalicylic acid should begin to form crystals as it cools.
+:7. After 10 ml of the ice-cold water has been added, cool the flask and contents in the ice water bath for 10 minutes, occasionally stirring the contents with a glass rod. The acetylsalicylic acid should begin to form crystals as it cools.
-. Preweigh the combined mass of a piece of filter paper and watch glass using the top-loading balance and record the combined mass in your lab notebook. Collect the crystals using suction filtration as shown in prelab. Wash crystals with ice cold water, using the other test tubes in the ice bath. Once all crystals are transferred into the filter system and are dry, carefully transfer the crystals and filter paper, without losing any aspirin, to a watch glass and place in your lab drawer to fully dry.  You will weigh the aspirin next week. We will be using the synthesized aspirin in the next lab activity.
+:8. Preweigh the combined mass of a piece of filter paper and watch glass using the top-loading balance and record the combined mass in your lab notebook. Collect the crystals using suction filtration as shown in prelab. Wash crystals with ice cold water, using the other test tubes in the ice bath. Once all crystals are transferred into the filter system and are dry, carefully transfer the crystals and filter paper, without losing any aspirin, to a watch glass and place in your lab drawer to fully dry.  You will weigh the aspirin next week. We will be using the synthesized aspirin in the next lab activity.
 Calculations for this weeks work will be completed at the beginning of next week’s lab. There is no reporting sheet for this week.
 TURN IN CARBON COPIES AT THE END OF EACH LAB PERIOD!
-−
 ===Instructors Notes.===

@@ Line 3: / Line 3: @@
 ===PRELAB===
 Complete the following Pre-lab assignment in your lab notebook prior to starting the lab.
-. Write out the synthesis reaction shown in Scheme 1 in your lab notebook.
+:1. Write out the synthesis reaction shown in Scheme 1 in your lab notebook.
-. Balance the reaction if needed.
+:2. Balance the reaction if needed.
-. Calculate the molecular mass of salicylic acid (A) and acetylsalicylic acid (C). Show your work.
+:3. Calculate the molecular mass of salicylic acid (A) and acetylsalicylic acid (C). Show your work.
-. Calculate the theoretical yield (the amount) of acetylsalicylic acid staring with 1.98g of salicylic acid. Show your work.
+:4. Calculate the theoretical yield (the amount) of acetylsalicylic acid staring with 1.98g of salicylic acid. Show your work.
 [[File:Scheme 1- The synthesis of aspirin.png|400px|thumb|center]]
@@ Line 12: / Line 12: @@
 '''CAUTION!  In this lab you will be handling acetic anhydride (B) and concentrated sulfuric acid. Both of these compounds are strong irritants to your skin, please handle these with care. Notify your instructor or TA to assist in cleaning up any spills.
 '''
 ===PURPOSE===