# Chemistry Topic 3 Quantitative Chemistry Help!!

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#1
I am stuck on this question: 0.0345 grams of hydrochloric acid is reacted with 0.05 grams of ethene. 0.0022 grams of ethyl chloride is obtained. What is the percentage yield of ethyl chloride? Leave your answer to one decimal place.
1
1 month ago
#2
0.0345g +0.05g= 0.845

0.0845/0.0022= % yeild= 38.40909091...
= 38.4 (1dp)
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#3
(Original post by Blackrose06)
0.0345g +0.05g= 0.845

0.0845/0.0022= % yeild= 38.40909091...
= 38.4 (1dp)
mm I'm not sure that is correct..?
0
1 month ago
#4
%yield = (actual yield/theoretical yield) x 100
%yield= (0.0022/0.0845)x 100= 0.2603550296.........
= 0.3(1dp)

sorry i messed up the formula a bit. ^^^corrected version
0
#5
(Original post by Blackrose06)
%yield = (actual yield/theoretical yield) x 100
%yield= (0.0022/0.0845)x 100= 0.2603550296.........
= 0.3(1dp)

sorry i messed up the formula a bit. ^^^corrected version
ohh okay, thanks n that's fine but i have a question - why do we not use moles here?
0
1 month ago
#6
because it's grams, i think. like when you work out concentration, its moles= concentration x Volume. but it can also be Mass= Concentration x Volume. it depends on the question. i think it could be the same for moles though.
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