Question

I'm missing something :p

Answer 1

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 \(67.6\)%

Answer 2

\[M_r(CH_3CH_2COOCH_2CH_3)=102g/mol\]
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%

Answer 3

You are correct @.Sam.

Answer 4

But the answer is 32.4% and 67.6% :(

Answer 5

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

Answer 6

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

Answer 7

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

Answer 8

Best choice. :)

Answer 9

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%

Answer 10

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

Answer 11

yw! :)

Answer 12

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

Answer 13

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

Answer 14

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

Answer 15

:)