Question about Paper Chromatography: Is Black Ink Really Black? activity

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tdrost
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Question about Paper Chromatography: Is Black Ink Really Black? activity

Post by tdrost »

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We have completed this experiment and are putting together our results. Can you help us understand the pie charts we are to use? Do we split the pie in half for two colors and in thirds for three colors or are there other numbers we are to use?
Thank you for the help.
The Drosts




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audreyln
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Re: Question about Paper Chromatography: Is Black Ink Really Black? activity

Post by audreyln »

Hello Drosts,

This sounds like a fun project! Your intuition is correct, the pie chart with have two "pieces" for two-colors and three "pieces" for three colors. The size of the pie "pieces" will be the average Rf values you calculated. For example if a blue color has an Rf value of 2.5 and a green color has an Rf value of 1.5, the blue portion of the pie chart will be larger than the green portion.

Good luck,

Audrey
tdrost
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Re: Question about Paper Chromatography: Is Black Ink Really Black? activity

Post by tdrost »

Thank you for the help. We are still not sure how to determine the size of the pie chart pieces because the Rf values do not add up to a whole. Our understanding is that the Rf values are only used to identify a component not to determine how much of it is in the ink. Is that correct? We would like to have a visual on the presentation board to help show the results, but we are just not understanding the best way to do this. Any further explanation would be appreciated.
Thanks,
The Drosts
audreyln
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Re: Question about Paper Chromatography: Is Black Ink Really Black? activity

Post by audreyln »

Hello Drosts,

I completely agree that the procedure's suggestion to use a pie chart is unusual and not the best visual. The Rf values will not add up to a whole.

I think a bar chart for each ink would be more appropriate with a separate bar for each color and the high corresponding to the Rf value.

Audrey
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