Question

You have been provided five standards and one unknown dilution of a dye. Spectrophotometer was used to measure the absorbance at 600 nm wavelength of the standards.

Dilution Ratio	Absorbance at 600 nm	Dilution
1 : 2,560	0.791	0.000390625
1 : 5,120	0.389	0.0001953125
1 : 10,240	0.199	0.00009765625
1 : 20,480	0.101	0.000048828125
1 : 40,960	0.053	0.0000244140625
Unknown 1 : ????	0.541

On a spreadsheet (Excel or Google sheet), create an appropriately labeled graphical plot of your data and also state your predicted fold-dilution of your Unknown based on its A600 reading. Then, upload your graph (it can be an excel file, or a screenshot of the image of your graph) to the link provided for this question.

Im having trouble on how to even set this up what would i put on the x axis and the y? Please help and explain!!!

Answer 1

X axis would the dilution and Y axis is for absorbance (OD)

Absorbance of unknown sample is 0.541

y = 2013.4x + 0.0018

y=0.541

x= 0.541-0.0018/2013.4

x=0.5392/2013.4

x=0.0002678

Dilution ration would be

1/0.0002678

=3743.13

Therefore the ratio of unknown sample (Abs 0.541) would be

1: 3734