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## .Sam. 2 years ago I'm missing something :p

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1. .Sam.

A sample of ethyl propanoate is hydrolysed by heating under reflux with aqueous sodium hydroxide. The two organic products of the hydrolysis are separated, purified and weighed. Out of the total mass of products obtained, what is the percentage by mass of each product? \(\color{blue}{Ans:}32.4% and 67.6 \)% and \(67.6\)%

2. .Sam.

\[M_r(CH_3CH_2COOCH_2CH_3)=102g/mol\] Separated compounds should be carbox and alcohol right \[M_r(CH_3CH_2COOH)=74g/mol\] \[M_r(HOCH_2CH_3)=46g/mol\] What I've found was 38.3% and 61.7%

3. mathslover

You are correct @.Sam.

4. .Sam.

But the answer is 32.4% and 67.6% :(

5. mathslover

The answer (from wherever it has been taken) is wrong.

6. mathslover

The products of the hydrolysis are correct; the molecular masses are also correct then there is nothing left which could be wrong.

7. .Sam.

Hmm I still can't trust my answer, we'll wait for more opinions from others okay :)

8. mathslover

Best choice. :)

9. emcrazy14

You did a mistake in there. The base hydrolysis of esters results in a sodium salt rather than carboxylic acid itself. So, here you'll get sodium propanoate i.e CH3CH2COONa So your Mr will be 96. Now, your percentage by mass of each product will be: (96/142) x 100= 67.6% (46/142) x 100= 32.4%

10. .Sam.

Oh yeah we're not using \(H_2O\) to hydrolyse that ester, derp... Okay got it, thanks @emcrazy14 :)

11. emcrazy14

yw! :)

12. mathslover

Oh, I did 96 + 46 = 162 :D , good work @emcrazy14

13. KL-RC

First of all thanks A LOT for posting this question Sam and No wonder, I was thinking that why is he writing a product of esterification?? instead of a sodium salt?? either way thanks you all! ;D

14. KL-RC

and @emcrazy14 you too!! thanks!!! :D

15. emcrazy14

:)

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