need help with a graph , concentration vs absorbance, linear

[deebird24]

Hey folks,

Any help for this would be gratefuly recieved. I am so confused about where I went wrong recently with a graph. I used Excel, and converted the numbers into LOG to allow for a greater spread of the data, but my lecturer has now asked me WHY did I do that?

 

As you can see the data points have quite a high range, as the concentration was diluted by it's exponent each time (is that the correct term?) I'm not great at maths, but it was diluted by half each time. The absorbance given was the Y axis. I got a straight line and was using the line to find an unknown concentration based on y=mx+c if that makes sense? Please reply to me in non=maths speak, as I am so poor at maths. I have called a local tutor to come help me in the meantime, but I'd love to hear back if anyone knows how they could have plotted this on Excel without all data values being clumped at the bottome of the graph, without converting to LOG

 

Concentration Absorbance

3000 3.148

1500 1.627

750 0.88

375 0.453

187.5 0.257

93.75 0.146

46.88 0.095

23.44 0.076

11.72 0.057

5.86 0.05

2.93 0.047

1.46 0.042

 

As you can see the concentration was double dilution, and I felt the only way I could fit this into a coherent graph was to convert it into LOG, but my lecturer has said, why did you that?

[Bignose]

From what I read, your lecturer didn't necessarily say what you did was wrong, but asked you why you did what you did...