Question

A plant extract was analyzed by UV-vis spectroscopy and the following data were obtained: What is...

A plant extract was analyzed by UV-vis spectroscopy and the following data were obtained:

What is the molar absorptivity of the chromophore?

Concentration (M)

Absorbance

5 X 10-5

0.051

10 X 10-5

0.098

15 X 10-5

0.157

Hint: You need to look at the units of molar absorptivity. Rise over run?

0 0
Add a comment Improve this question Transcribed image text
Answer #1

Kindly rate positive and do comment for any doubt.

Add a comment
Know the answer?
Add Answer to:
A plant extract was analyzed by UV-vis spectroscopy and the following data were obtained: What is...
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions
  • (10 pts) The iron content of a well water sample is determined by UV-Vis spectroscopy. A...

    (10 pts) The iron content of a well water sample is determined by UV-Vis spectroscopy. A 10.00 mL aliquot of well water is transferred to a 100.0-mL volumetric flask and 20 mL of 0.10 M nitric acid is added to oxidize iron (II) to iron (II). Next 30 mL of a 0.1 M sodium thiocyanate solution is added to form the deep red complex iron (II) thiocyanate. The solution is diluted to volume with DI water. A reagent blank is...

  • A caffeine sample was diluted by a factor of 1000 and UV-Vis spectra of diluted solution...

    A caffeine sample was diluted by a factor of 1000 and UV-Vis spectra of diluted solution showed Absorbance of 0.0340 at 275nm. The concentration of diluted sample was determined as 2.76 × 10-5 Mol. What is the Molar Absorptivity (e) of caffeine at 275nm in both the diluted and concentrated solutions? Consider thickness of a cuvette – 1cm.

  • 5 A calibration curve used in UV/VIS spectroscopy plots concentration on the y-axis and absorbance on...

    5 A calibration curve used in UV/VIS spectroscopy plots concentration on the y-axis and absorbance on the x-axis. O A) True OB) False Question 5 (2 points) A working standard is prepared by taking 38.00 mL of a 500.0 ppm stock solution and diluting it tos a final volume of 650.0 mL. Calculate the ppm concentration of the working solution. Provide your answer to two places after the decimal and without units. Your Answer: Answer Submit Out 2afactione ad

  • Table 1. Concentrations of [Fe(Phen),1?, M, in water and UV- vis absorbance values recorded at 2...

    Table 1. Concentrations of [Fe(Phen),1?, M, in water and UV- vis absorbance values recorded at 2 -505 nm. Concentration of [Fe(Phen)/, M Absorbance 9.500 x 10 0.999 4.250 x 10 0.480 0.219 2.125 10% 1.063 x 10 0.104 0.000 0.003 Table 2. UV-vis absorbance values of [Fe(phen)]* held at 35 °C after mixing with H SO, and recorded at 5 minute intervals (in water at max = 505 nm). Time (minutes) Absorbance 0.997 0.935 0.877 0.823 0.772 0.724 0.680 0.638...

  • need help on these Suppose you obtained the following data from two standard solutions of known...

    need help on these Suppose you obtained the following data from two standard solutions of known concentrations using a UV-Vis spectroscope: Analysis # Conc. (mg/L) 8.00 20.00 Absorbance (at 255 nm) 0.160 0.390 What is the concentration (in mg/L) of an unknown solution with an absorbance of 0.200 at 255 nm 10 points)? The unknown solution contains the same analyte as the standard solution does (Assume a path length of 1cm). 10. You prepared a stock solution by dissolving a...

  • Part 2. UV-Visible Spectroscopy Cut2 concentration Absorbance (mol/L) 0.0010 0.053 0.0025 0.128 0.0050 0.251 0.0075 0.378...

    Part 2. UV-Visible Spectroscopy Cut2 concentration Absorbance (mol/L) 0.0010 0.053 0.0025 0.128 0.0050 0.251 0.0075 0.378 0.0100 0.510 Diluted unknown, Trial 1 0.079 For your lab notebook: C. Sketch how you could make each of the the 5 standards for Part 2 from a 0.100 mol/L Cu2+ stock solution, 1.25 mol/L NH3 solution, and Dl water. The procedure is referenced in step 2b. Assume you would use 10-mL volumetric flasks to make the solutions. d. Sketch also how you would...

  • 4. The following data was obtained for an ac solution of Picric acid of 9.5 x...

    4. The following data was obtained for an ac solution of Picric acid of 9.5 x 10-‐5 M using a uv-vis spectrophotometer and 0.5 cm cells λ (nm) 330 350 370 390 400 410 430 450 A 0.18 0.28 0.40 0.45 0.52 0.45 0.33 0.12 a) realice graoh of the absorption spectrum of absorptivity molar Coefient (ε) as a function of λ b) Select the optimal wavelength to take the reading on a calibration curve

  • please answer 1-4 &6 Questions The energy of UV light is 70 kcal/mole at 400 nm...

    please answer 1-4 &6 Questions The energy of UV light is 70 kcal/mole at 400 nm and 140 kcal/mole at 200 nm. Why is UV radiation damaging to the eyes and skin? (Hint: Think about the energy required to break a C-C bond.) 2. Which is more energetic: 235 nm or 325 nm light? Explain. 3.) Why is UV spectroscopy used more frequently in organic chemistry than visible spectroscopy? 4. Using the structure of methyl orange as an example, draw...

  • Use your own words to describe what is a reversible reaction and define dynamic equilibrium. What...

    Use your own words to describe what is a reversible reaction and define dynamic equilibrium. What is the equilibrium Keg expression for the chemical reaction performed in this lab? (5 points) 2.Explain what is the purpose of using UV-vis spectroscopy for this particular experiment. What is the maximum wavelength in nm that the TA used to collect the absorbance value of Fe(SCN)2+ ? (5 points) 3.Use the absorbance and concentration data provided in the first part of the TA video...

  • Pre-Lab Assignment 1) Draw the reaction mechanism for the reaction. 2) Determine the limiting reagent. Procedure...

    Pre-Lab Assignment 1) Draw the reaction mechanism for the reaction. 2) Determine the limiting reagent. Procedure 1 Place approximately 1 g of stilbene dibromide prepared in last week's experiment in a 50 mL round bottom flask. Record the exact mass. Add 0.8 g of KOH and 4 mL of triethylene glycol from the syringe provided in the fume hood (rinse any crystals from the sides of the flask while adding triethylene glycol). 2 Heat the stirred reaction mixture to a...

ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT