maniccrammer
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I have to explain the relationship between glucose concentration and absorbance value in these solutions we tested in class - I’m so confused?? I’ve said for describe the relationship that as conc increases the absorbance value also increases but I’m not sure about the explain part
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Rockman501
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This is because when you add Benedict's solution to a non reducing sugar (after boiling with dilute HCl), the solution turns from blue to brick red. This change in colour means that if there is a greater concentration of the non reducing sugar, the colour of the solution will be darker and so absorbs more light (or prevents more light from passing through), so absorbance increases (or light transmission decreases)
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Huckipity
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(Original post by Rockman501)
This is because when you add Benedict's solution to a non reducing sugar (after boiling with dilute HCl), the solution turns from blue to brick red. This change in colour means that if there is a greater concentration of the non reducing sugar, the colour of the solution will be darker and so absorbs more light (or prevents more light from passing through), so absorbance increases (or light transmission decreases)
Bang on
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Rockman501
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(Original post by Huckipity)
Bang on
Haha thanks man
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Huckipity
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(Original post by Rockman501)
Haha thanks man
Wait, actually you have the right answer, however you may only get 3/4 marks. This is because the reason the absorbance value decreases is due to the copper (I) oxide forming which is an insoluble precipitate so it blocks the light, not because red is a darker colour than blue. Still, props for getting the right idea though
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maniccrammer
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(Original post by Huckipity)
Wait, actually you have the right answer, however you may only get 3/4 marks. This is because the reason the absorbance value decreases is due to the copper (I) oxide forming which is an insoluble precipitate so it blocks the light, not because red is a darker colour than blue. Still, props for getting the right idea though
Thank you!
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