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Esterfication help! (1 Viewer)

SanjoyM

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Okay, this is a simple question, but I think I'm stuck:
Explain why citric acid is not a suitable catalyst for esterfication?

Assess the risks involved in an investigation to produce esters and describes the procedures to minimise these risk (3 marks)

I was thinking about wearing goggles, maintaining a distance, treating the equipments with care? Any others?

Can someone help me please?

Thank you:)
Just started learning about esters, so a bit confused lol
 

Dylanamali

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boiling chips - spread heat out evenly -> reactants are volatile so you don't want immense heat on one location.

refluxing equipment - allows the volatile reactants to be heated, yet due to the refluxing equipment there is no risk of an explosion through a pressure buildup (if it were a closed system).
 

SanjoyM

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So, there are minimal risks involved, but the experiment does pose possible harmful risks? I always stumble on these questions about safety! LOL
Thank you:)
What about the first one?
'Explain why citric acid is not a suitable catalyst for esterfication?"
 

Dylanamali

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not sure.. never come across that question before.

Perhaps it's strength (as a weak acid) makes it unsuitable as a catalyst?

I think the best answer would have to be that concentrated sulfuric acid, not only acts as a catalyst in the reaction, but it also has the ability to shift the equilibrium to favour the side of the products and thus favour the production of ester (increase the yield). It does this through it's property as a dehydrating agent - decreasing the concentration of the water and thus causing the eq. position to favour the products. Perhaps, because citric acid does not have this property as a dehydrating agent it is unsuitable as a catalyst. But then again, catalysts generally have no effect on equilibrium position. So i'm not sure.
 

iampeterr

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citric acid is not suitable because it doesn't dehydrate the solution.
concentrated h2so4 removes water from the products, therefore shifting the equilibrium to the right to increase the yield (ester).
 

Enzym3

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Esterificiation is a dehydration reaction and therefore requires a strong acid as a catalyst, citirc acid is triprotic but it isn't strong (i.e. doesn't fully ionize) and therefore won't cause dehydration


Risk Process to manage risk

Alkanol is flammable heat in a water bath (or with boiling chips, or both) avoid naked flame

Glass wear is breakable Never run with glassware, report any breakages to lab supervisor immediately
and can be sharp

sulfuric acid (catalyst) If spilled onto skin rinse with water immediately and inform first aide officer
is corrosive and harmful
 

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