Question

Your advisor has given you a tube of GMP that has been sitting in the freezer for many years and wants to know the concentration. There is one problem: the spectrophotometer in the lab has been 'optimized' for use with proteins and only measures at 280 nm. You decide to give it a try. After getting and absorbance reading of 0.2, what is the concentration of GMP in the tube (assuming a 1 cm path length).

Answer 1

2.22 × 10^-5M

Step-by-step explanation:

From Beer-Lambert's law;

A=εcl

Where A = absorbance of GMP= 0.2

ε= molar extinction coefficient of GMP = 9000 M-1cm-1

c= concentration of GMP= the unknown

l= path length = 1 cm

c= A/εl = 0.2/ 9000 M-1cm-1 × 1 cm

c= 2.22 × 10^-5M