Question

The absorbance of a chemical solution is 0.5 at 400 nm. The concentration of the solution...

The absorbance of a chemical solution is 0.5 at 400 nm. The concentration of the solution is 50 mM. The pathlength of the cuvette is 1 cm. What is the molar absorptivity of the chemical at this wavelength?

Science   Biology   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

The formula for absorbance is :- A = ɛ x l x c

In this, A is absorbance, ɛ is molar abaorptiviy, l is length of the cuvette and c is the concentration of the solution.

Now we can move the equation for ɛ and it becomes :-

ɛ = A/lc (Here we took lc to the other side)

Now we have the values of A, l and c given.

A is 0.5

c is 50mM = 0.05 M (We converted it into M by dividing 50 with 1000)

l is 1 cm

So putting the values in the equation

ɛ = 0.5/(1 X 0.05)

ɛ = 10 L Mol-1 cm-1

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Calculate the molar concentration of a solution that has a measured absorbance of 0.635 using a...
Calculate the molar concentration of a solution that has a measured absorbance of 0.635 using a 1-cm pathlength cuvette and an extinction coefficient of 46,000.0 M-1cm-1.
Ergosterol, a precursor of vitamin D, has δmax = 282 nm and molar absorptivity ε =...
Ergosterol, a precursor of vitamin D, has δmax = 282 nm and molar absorptivity ε = 11,900 M-1cm-1. 1). What is the concentration of ergosterol in a solution whose absorbance A = 6.5×10-2 with a sample pathlength l = 1.00 cm. 2). What is the absorbance of a solution having a concentration of ergosterol of 5.2×10-5 M with a sample pathlength l = 1.00 cm?
At 280 nm the chemokine CCL19 has an extinction coefficient of 8730 M-1cm-1. A solution of...
At 280 nm the chemokine CCL19 has an extinction coefficient of 8730 M-1cm-1. A solution of CCL19 is diluted 50 fold. After dilution (in a cuvette with a 1 cm pathlength) the absorbance at 280 nm is 0.112. What is the concentration of the undiluted CCL19 solution? 978 M 1.28 X 10^-5 M 641 µM 1.00 x 10^6 mM
PLEASE SHOW ALL WORK 1a. To create the calibration curve a 5.00 cm pathlength cuvette was...
PLEASE SHOW ALL WORK 1a. To create the calibration curve a 5.00 cm pathlength cuvette was used in a spectrophotometer to measure the absorbance of a series of standard solutions. The wavelength used was 350 nm. The Beers law plot showed a linear function with the equation of y = 204.5x + 0.1.   If a sample of the same species with an unknown concentration is poured into a 1.00 cm pathlength cuvette and the resulting absorbance was 0.175, what would...
are measuring the concentration of Fe2 in a sample by measuring the absorbance of its complex...
are measuring the concentration of Fe2 in a sample by measuring the absorbance of its complex with ferroxine. Your sample, measured in a 1.00-cm pathlength cuvette, has an absorbance of 0.208 while the reagent blank in the same cuvette has an absorbance of 0.046. What would be the absorbance reading of these two solutions if measured in a cuvette with 8.00 cm pathlength?
If a solution has an absorbance of 0.100 in a 1.00 cm pathlength cuvette, what would...
If a solution has an absorbance of 0.100 in a 1.00 cm pathlength cuvette, what would the absorbance be in a cuvette of 0.55 cm pathlength cell?
5) What is the absorbance at 280 nm of a 3 µL of 1µM protein solution...
5) What is the absorbance at 280 nm of a 3 µL of 1µM protein solution with a molar absorptivity of 23,000 cm-1 M-1 measured in a 0.1cm path length cell? Explain the molecular basis for this phenomena.
An acid-base indicator, HIn, dissociates according to the following reaction in an aqueous solution. HIn---> In-...
An acid-base indicator, HIn, dissociates according to the following reaction in an aqueous solution. HIn---> In- + H+ . The protonated form of the indicator, HIn, has a molar absorptivity of 3827 M–1·cm–1 and the deprotonated form, In–, has a molar absorptivity of 26210 M–1·cm–1 at 440 nm. The pH of a solution containing a mixture of HIn and In– is adjusted to 5.92. The total concentration of HIn and In– is 0.000117 M. The absorbance of this solution was...
25.0 ml C solution is diluted to 50.0 ml and the absorbance is 0.416 in 348...
25.0 ml C solution is diluted to 50.0 ml and the absorbance is 0.416 in 348 nm in a 1.00-cm cuvette. 25.0 ml second solution is added 10.0 ml solution that contains 23.4 ppm of C. After diluted to 50.0 ml this solution has absorbance 0.610 in the same cuvette and wavelength. Calculate concentration (ppm) C in sample.
By Beer’s Law, determine the molar absorptivity of the iron (II) phenanthroline complex using maximum absorbance,...
By Beer’s Law, determine the molar absorptivity of the iron (II) phenanthroline complex using maximum absorbance, the molar concentration of the standard iron solution, and the cell path length. I'm confused because on this lab we have calculated the max Wavelenth (497nm) and used a spectroscopy instrument to measue the max Absorbance at that wavelength for the other samples and unknown. Beers law seem simple, But how would I use it to find the molar absorptivity? SAMPLE (in ppm) Max...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT