How much is the molar extinction coefficient of methylene
blue at wavelenght 664 nm? Are molar extinction coefficient
depend on concentration of solution?

Answer Posted / bob

At 664, it's 74028. Extinction coefficient is not dependent
on concentration, but absorption is directly dependent on
concentration and the distance (length) that the light must
travel through the solution. So you can use a very thin
layer of concentrated solution, or a test-tube full of a
less-concentrated solution to get the same absorbance.

A = e*c*d.
e = extinction coefficent
c = concentration (molarity)
d = depth (optical path length)

Is This Answer Correct ?    20 Yes 5 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

what are UV rays absorbs slightly?

1639


What can be the supporter of combustion except oxygen.

2350


a sample of gas occupies a volume of {450.0 ml}at {740 mm Hg}and[16C]determine the volume of this same sample at [760 mm Hg]and [37c]?

4512


WHAT IS THE SYLLABUS OO GROUP -I?

1726


why athanol-water mixtuere have maximum viscocity in wt% 40?

1269






Why does the experimental lattice enthalpy of NaI differ greatly from the theoretical lattice enthalpy?

2948


what is the difference between elctrefining and electrolysis?

1749


In testing of Cement the formula for water requirement for setting time is as below- Water required for setting time = NC x 0.85 The question is that what is the logic of 0.85 in this formula??

2030


. Given that 2Hg2+ (aq) + 2 e- Hg22+(aq) E0 =0.92V Hg22+ (aq) + 2 e- 2Hg(l) E0 =0.85V Calculate standard free energy change and K for the following process at 25oC Hg22+(aq) Hg2+ (aq) + Hg(l)

6010


4 Identify the substance oxidized, reduced, oxidizing agent and reducing agent for the following reactions

2010


what kind of question can be asked in interview for polarimeter related ?

4728


Normally entropy is expressed as q/T. But, work and heat have same unit. Why can't it be replaced by work?

1778


The rate constant for the second order reaction is 0.54/M.s at 300oC. How long (in sec) would it take for the concentration of NO2 to decrease from 0.62M to 0.28 M? 2NO2(g) 2 NO(g) + O2(g)

2162


What is the requirement to give RFlow when using RID detector?

2588


What is the brigg's raucher reaction?

1845