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My experimental value is very different from the literature value. Will I lose marks?


TheDaringPopo

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I'm doing a lab report on measuring enthalpy, and I obtained a value that is VERY different from the literature value that I got off the net. I know why I got it wrong, and I have addressed that in my evaluation, but will IB cut marks for obtaining an answer that is far from the literature value? I know that an answer can never be accurate, but my value is causing a standard deviation of more than 50%, which is way too high. Do I have much to lose?

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Is this for your IA?

Apparently, for Chemistry, if your percentage error was less than 40%, the IB will suspect you've fiddled with your data. It means you have a lot to evaluate on if you have a high error, which is good.

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Is this for your IA?

Apparently, for Chemistry, if your percentage error was less than 40%, the IB will suspect you've fiddled with your data. It means you have a lot to evaluate on if you have a high error, which is good.

That is interesting! Where did you hear that? I believe it, but I always feel more comfortable with a source! :) My teacher has shown us past labs of people who made up their data, and it is an awful sight to see!

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Is this for your IA?

Apparently, for Chemistry, if your percentage error was less than 40%, the IB will suspect you've fiddled with your data. It means you have a lot to evaluate on if you have a high error, which is good.

That is interesting! Where did you hear that? I believe it, but I always feel more comfortable with a source! :) My teacher has shown us past labs of people who made up their data, and it is an awful sight to see!

https://www.youtube.com/watch?v=EEDTzqZpI2I&list=PL40E1D9490EB0D969&index=9

He's an associated IB examiner so

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Is this for your IA?

Apparently, for Chemistry, if your percentage error was less than 40%, the IB will suspect you've fiddled with your data. It means you have a lot to evaluate on if you have a high error, which is good.

That is interesting! Where did you hear that? I believe it, but I always feel more comfortable with a source! :) My teacher has shown us past labs of people who made up their data, and it is an awful sight to see!

https://www.youtube.com/watch?v=EEDTzqZpI2I&list=PL40E1D9490EB0D969&index=9

He's an associated IB examiner so

Ah, yes, I'm very familiar with Thornley! He's really great, isn't he? As to the topic at hand, I suppose you can take that rule and apply it to other experiments. He was using it in that video specifically to talk about the heat being lost, but I suppose it is an okay rule to live by :)

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Is this for your IA?

Apparently, for Chemistry, if your percentage error was less than 40%, the IB will suspect you've fiddled with your data. It means you have a lot to evaluate on if you have a high error, which is good.

That is interesting! Where did you hear that? I believe it, but I always feel more comfortable with a source! :) My teacher has shown us past labs of people who made up their data, and it is an awful sight to see!

https://www.youtube.com/watch?v=EEDTzqZpI2I&list=PL40E1D9490EB0D969&index=9

He's an associated IB examiner so

Ah, yes, I'm very familiar with Thornley! He's really great, isn't he? As to the topic at hand, I suppose you can take that rule and apply it to other experiments. He was using it in that video specifically to talk about the heat being lost, but I suppose it is an okay rule to live by :)

God I love Thornley so much ^_^

But my teacher encouraged us to do a rubbish experiment so we'd have lots to evaluate XD

Edited by Bude
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Is this for your IA?

Apparently, for Chemistry, if your percentage error was less than 40%, the IB will suspect you've fiddled with your data. It means you have a lot to evaluate on if you have a high error, which is good.

While in many ways it's good to have experimental values which do not exactly coincide with the literature values, I wouldn't go so far as to say that the IB will suspect you've fiddled with your data if your % error was less than 40%. You can achieve full marks with errors of 10% or less, and in the same way you can achieve full marks with errors of 50%. The IB want to see that you have thought out your experiment logically in the Design and have tried to control as many variables that may REASONABLY be foreseen to be sources of error. Of course we're not expected to have foreseen every single source of error, which is why we have experimental errors which should facilitate an interesting Evaluation section.

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Is this for your IA?

Apparently, for Chemistry, if your percentage error was less than 40%, the IB will suspect you've fiddled with your data. It means you have a lot to evaluate on if you have a high error, which is good.

While in many ways it's good to have experimental values which do not exactly coincide with the literature values, I wouldn't go so far as to say that the IB will suspect you've fiddled with your data if your % error was less than 40%. You can achieve full marks with errors of 10% or less, and in the same way you can achieve full marks with errors of 50%. The IB want to see that you have thought out your experiment logically in the Design and have tried to control as many variables that may REASONABLY be foreseen to be sources of error. Of course we're not expected to have foreseen every single source of error, which is why we have experimental errors which should facilitate an interesting Evaluation section.

I agree with what you say in that it would be stupid to penalise students for too accurate an experiment, I'm going to go with the source I linked. It just so happens that I had large percentage errors.

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