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HELP HELP!

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its the mass thats given over the mass you had at the beginning... i need an example to explain it better..
Thats the percentage yield. Im talkin about the percentage error or percentage uncertainty...
 
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Can someone explain percentage error calculation? :/

= Error/actual measurement * 100

Example .

56cm3 of Hydrogen was given off in a reaction between Mg and HCl . Assuming reading accuracy of the measuring cylinder is + or - 3 . Find the percentage error.

3/56 * 100 = + or - 5.4%

Or :

The actual mass of a compound is 46.86g and the measured mass is 49.86g find the percentage error .

Wrong measurement - actual measurement / actual measurement * 1oo

49.86 - 46.86/ 46.86 * 100 = 6.4 %
 
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Yeah. Thats correct.
yeh so basically its the error/the actual thing *100... smetimes for the mass you need to check the equation and check the mole ratio.. for ex:.mass used for KHCO3= 2.00g and in the equation its 2KHCO3 error of mass =+-0.01g... therefore 2*0.01/2.00 *100
 
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yeh so basically its the error/the actual thing *100... smetimes for the mass you need to check the equation and check the mole ratio.. for ex:.mass used for KHCO3= 2.00g and in the equation its 2KHCO3 error of mass =+-0.01g... therefore 2*0.01/2.00 *100
Thanks alot! :)
 
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Can someone help me with the Iodine-thiosulfate titrations? like explain it to me. The calculations and steps.
 
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where did you find that?
Its there on the June 2010 Unit 3 paper. Question 3. Its about that titration. In my text book they have that topic but i don't completely understand the calculations. That is why i would like someone to explain it to me.
 
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Its there on the June 2010 Unit 3 paper. Question 3. Its about that titration. In my text book they have that topic but i don't completely understand the calculations. That is why i would like someone to explain it to me.

I have Unit 3 in June so I can't help sorry :)
 
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im giving unit 3b chemistry tommorrow..edexcel
if any one has some questions related to that let me know..i would love to discuss them over here.
 
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