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Chemistry p1(NIGHTMARE) Coming

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slammer951:
Can anyone help me with this question?

30) Use of the Data Booklet is relevant to this question.
Ethyl ethanoate can be obtained from ethanoic acid and ethanol by the following reaction.
CH3CH2OH + CH3CO2H = CH3CO2CH2CH3 + H2O
Ethanol (30 g) and ethanoic acid (30 g) are heated under reflux together, and 22 g of ethyl
ethanoate are obtained.
What is the yield of the ester?
A 25 % B 38 % C 50 % D 77 %

This is question 30 , November 08

s16:
thank u for answering my qs..

aiyo12345:

--- Quote ---Can anyone help me with this question?

30) Use of the Data Booklet is relevant to this question.
Ethyl ethanoate can be obtained from ethanoic acid and ethanol by the following reaction.
CH3CH2OH + CH3CO2H = CH3CO2CH2CH3 + H2O
Ethanol (30 g) and ethanoic acid (30 g) are heated under reflux together, and 22 g of ethyl
ethanoate are obtained.
What is the yield of the ester?
A 25 % B 38 % C 50 % D 77 %

This is question 30 , November 08
--- End quote ---

The answer would be C - 50%.
You have to calculate the moles of both ethanol and ethanoic acid and take the smaller value.
(since they react in 1:1 ratio, one with more moles would be in excess)
the aformentoned value of moles would equal the theoretical yield of ester in moles
(as again, they are in one:one ratio i.e. one mole of ethanoic acid reacts with one mole of ethanol to form one moles of ester)
then you can multiply RMM of ester given to the mole given to find theoretical yield in mass.
you then divide actual yield by theoretical yield.

Hope this helps  ;)
Meh if it doesn't.

slammer951:
Thanks for the help   ;D

khi2ruh:
can anyone please help me with Q4 Of nov08?

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