Question

Using a spectrophotometer, and a cuvette with a path length of 1 cm you measure the absorbance (A275) of Guanosine to be 0.70. Calculate the concentration of guanosine in your sample

Answer 1

Answer : The concentration of guanosine in your sample is, $8.33\times 10^{-5}M$

Explanation :

Using Beer-Lambert's law :

$A=\epsilon \times C\times l$

where,

A = absorbance of solution  = 0.70

C = concentration of solution = ?

l = path length = 1.00 cm

$\epsilon$ = molar absorptivity coefficient guanosine  = $8400M^{-1}cm^{-1}$

Now put all the given values in the above formula, we get:

$0.70=8400M^{-1}cm^{-1}\times C\times 1.00cm$

$C=8.33\times 10^{-5}M$

Thus, the concentration of guanosine in your sample is, $8.33\times 10^{-5}M$