Rinsing in Esterification? (1 Viewer)

[Rip the Jacker]

Theres these questions I have to answer for the esterification of ethanoic acid and 1-pentanol (1-pentyl ethanoate) - Worksheet 17 for those of you who use conquering chem.

Questions are:

Explain why the reaction mixture was washed firstly with water.

The (first) ester layer is slightly acidic. Why is it washed with Na2CO3?

If you need more information, tell me -

I have no idea what to do, since I think i was away when the class did the experiment so, any help would be greatly appreciated. Thanks in advance =D

 

[rnitya_25]

how can the reaction mixture be washed with water? if you mean why the reaction mixture vessel was washed with water, i think it is so that other chemicals that may have been in there previously don't alter the experiment's accuracy in results.

 

[Rip the Jacker]

how can the reaction mixture be washed with water? if you mean why the reaction mixture vessel was washed with water, i think it is so that other chemicals that may have been in there previously don't alter the experiment's accuracy in results.

yeah, thats what I thought...but thats what the question says - but I have no idea cuz I havent done the experiment

 

[rnitya_25]

oh ok..lol....we did it last term..can't remember it thoroughly though...just nits and bits

 

[nanashi]

Explain why the reaction mixture was washed firstly with water.

The (first) ester layer is slightly acidic. Why is it washed with Na2CO3?

dont know wat u mean by the first question...
as for Q2, Na₂CO₃ is a base, and will react with the acid in the upper ester layer. the water formed from neutralisation, along with other chemicals in the bottom layer, would then be separated from the top layer.

correct me if im wrong

 

[Templar]

Washing with water gets rid of any unreacted reagents, as both of them are soluble in water, and the ester is not.

 

[Rip the Jacker]

Thank you

 

[LaCe]

Just reiterating
steps to achieving ester from standard solution:
1. Transfer to separating funnel
2. Wash with water to get trid of any unreacted reagents
3. Add NaHCO3 or Na2CO3 to remove any excess acid/to neutralise acid
3. Discard lower aqueous layer
4. Distill crude ester to achieve higher purity