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Chemistry help

image.jpg Can someone help me with number 5b and explain how we get that I missed a couple of classes and I have no clue

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Percentage yield= how much you got
--------------------------------(divided by) (x100)
how much could possibly be made
(edited 8 years ago)
Reply 2
Avatar for Dora amos
Dora amos
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18
Original post by hxfsxh
Percentage yield= how much you got
--------------------------------(divided by) (x100)
how much could possibly be made


The answer is 86.9% in the book with no explanation
9.20/16.08= 0.547x100= 54.7% is wrong
Original post by vickie89uk
The answer is 86.9% in the book with no explanation
9.20/16.08= 0.547x100= 54.7% is wrong


Right give me a sec, I'll re-read the question
Reply 4
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Dora amos
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Original post by hxfsxh
Right give me a sec, I'll re-read the question


Thank you
Original post by vickie89uk
Thank you


I did this topic just a few months ago, but I'm totally lost as to how to get the answer. It could be the difference between NaHCO3 and Na2CO3, but I'm lost :/
Original post by vickie89uk
The answer is 86.9% in the book with no explanation
9.20/16.08= 0.547x100= 54.7% is wrong


You need to use your answer to part a
Reply 7
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Dora amos
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Original post by samb1234
You need to use your answer to part a
the answer is in the answers section I don't know how to get either of the answers I'm confused

Original post by hxfsxh
I did this topic just a few months ago, but I'm totally lost as to how to get the answer. It could be the difference between NaHCO3 and Na2CO3, but I'm lost :/


So Am I don't worry thanks though
Original post by vickie89uk
the answer is in the answers section I don't know how to get either of the answers I'm confused



So Am I don't worry thanks though


So it's a thermal decomposition reaction. That means that the only reactant on the left hand side of the reaction is NaHCO3, and we know that one of the products is Na2CO3. What can we tell about the number of NaHCO3 there must be, and what else could be produced which would help us to balance the equation
I can do part a but I'm lost on b :/
Original post by surina16
I can do part a but I'm lost on b :/


I'll get to part b in a minute :smile:, but there's no point explaining it until you understand part a
Original post by samb1234
I'll get to part b in a minute :smile:, but there's no point explaining it until you understand part a


is it anything to do with moles? :biggrin: that's all I can do on it haha
Original post by surina16
is it anything to do with moles? :biggrin: that's all I can do on it haha


indeed it is
Original post by samb1234
indeed it is


:banana:
Reply 14
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Original post by samb1234
So it's a thermal decomposition reaction. That means that the only reactant on the left hand side of the reaction is NaHCO3, and we know that one of the products is Na2CO3. What can we tell about the number of NaHCO3 there must be, and what else could be produced which would help us to balance the equation


Have we lost hydrogen so NA2CO3 + H20 (water vapour) + CO2

As water vapour and carbon dioxide are products of the reaction
Original post by vickie89uk
Have we lost hydrogen so NA2CO3 + H20 (water vapour) + CO2

As water vapour and carbon dioxide are products of the reaction


You're correct, you just need to realise what that means about the left hand side of the equation
Reply 16
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Original post by samb1234
You're correct, you just need to realise what that means about the left hand side of the equation


I don't know what that means for the left I thought we had then gained oxygen but I don't know
First you need to balance the equation. So it would become
2NaHCO3 -------> Na2CO3 + H2O + CO2
Original post by vickie89uk
I don't know what that means for the left I thought we had then gained oxygen but I don't know


If you have Na2co3 and h2o there must have been 2 nahco3 in the first place, make sense?
Reply 19
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Original post by Nikitha13
First you need to balance the equation. So it would become
2NaHCO3 -------> Na2CO3 + H2O + CO2


Yep I've got that

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