1. The formula for
absorbance is given as:
A = log (Io / I)
where A is absorbance, Io
is initial intensity, and I is final light intensity
log (Io / I) = A
log (Io / I) = 2
Io / I = 100
Taking the reverse which is
I / Io:
I / Io = 1 / 100
I / Io = 0.01
Therefore this means that
only 0.01 fraction of light or 1% passes through the sample.
2. What is meant by
transmittance values is actually the value of I / Io. So calculating for A:
at 10% transmittance = 0.10
A = log (Io / I)
A = log (1 / 0.10)
A = 1
at 90% transmittance = 0.90
A = log (Io / I)
A = log (1 / 0.90)
A = 0.046
So the absorbance should be
from 0.046 to 1
3. at 10% transmittance =
0.10
A = log (Io / I)
A = log (1 / 0.10)
<span>A = 1</span>
