universalcj
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Weigh 2.0 g of 2-Hydroxybenzoic Acid and Put it in a Pear Shaped Flask.
Clamp the Flask and Suspend it in a Beaker of Water.
Add 5.0 cm^3 of Ethanoic Anhydride and 5 drops of Concentrated Sulfuric Acid to the Mixture in the Flask
Fix a Condenser on the Flask.
In a Fume Cupboard , Warm the Mixture carefully Under Reflux in a the Water Bath using a Bunsen Burner for 5 minutes
Swirl the Mixture gently until All the Solid has Dissolved.
Remove the Flask from the Hot Water Bath and Add Crushed Ice and Distilled Water to Break down any Unreacted Ethanoic Anhydride.
Stand the Flask in a Bath of Iced Water until Precipitation is Complete.
Filter off the Product Under Reduced Pressure
Dissolve the Impure Product in the Minimum amount of Ethanol to a Conical Flask
Warm UNTIL the Mixture Nears the Boiling Temperature of the Mixture
Continue Adding Further Ethanol and Heating UNTIL All of the Soluble Solid has Dissolved
Allow the Liquid to Cool UNTIL Crystals of the Organic Solid have Formed( More Crystals can be Obtained by Cooling the Solution Below the Room Temperature in an Ice Bath )
the Mixture is then Filtered to Remove Soluble Impurities using a Buchner Funnel
the Crystals are Washed with a Small Amount of Ice-Cold Solvent and then Dried in a Desiccator
Calculate the Percentage Yield of the Product. & Measure the Melting Temperature of the Product

these are the steps for THE PREPARATION OF ASPIRIN CP 16 Chemistry

do we need to memorise this much precisely ?
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EierVonSatan
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You don't need to memorise the fine details - you do need to know the procedure. What I mean by that is you have to write down a method that someone else can follow to do the practical and explain why each step is important.

I would summarise the first few steps as:

1. Add ''mass'' 2-hydroxybenzoic acid to a flask, submerged in room temperature water. [or use a heating block]
2. Add ''volume/mass" ethanoic anhydride followed by x drops of H2SO4 to the flask.
3. Whilst stirring, heat the mixture to reflux.
4. After "time" allow the mixture to cool to room temperature and add ''volume" of distilled water.
5. Cool mixture in an ice bath until no more precipitate forms.

etc.
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universalcj
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(Original post by EierVonSatan)
You don't need to memorise the fine details - you do need to know the procedure. What I mean by that is you have to write down a method that someone else can follow to do the practical and explain why each step is important.

I would summarise the first few steps as:

1. Add ''mass'' 2-hydroxybenzoic acid to a flask, submerged in room temperature water. [or use a heating block]
2. Add ''volume/mass" ethanoic anhydride followed by x drops of H2SO4 to the flask.
3. Whilst stirring, heat the mixture to reflux.
4. After "time" allow the mixture to cool to room temperature and add ''volume" of distilled water.
5. Cool mixture in an ice bath until no more precipitate forms.

etc.
oh i got it!!! really really thank you !!!
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