You are measuring lycopene in samples of tomato sauce. You extract a 2.1 mL samp

Question

You are measuring lycopene in samples of tomato sauce. You extract a 2.1 mL sample of tomato sauce 3X with 5 mL hexane. You pool the extracts and bring to a final volume of 25 mL with hexane. You then evaporate the extract under N2 and resolubilize to a final volume of 3 mL hexane. You then measure the sample at 502 nm on an old school spectrophotometer that only measures intensity of the incident light (I0, 158 units) and the light transmitted through the sample (I, 54 units), and has a path length of 0.94 cm. The molar absorptivity of lycopene at 502 nm is 1.72 105 Lmol?1 cm?1 . The serving size of tomato sauce is 1 US legal cup.

Lycopene MW=536.89 g/mol, formula=C40H56

1. What is the light transmittance of the sample?

2. What is the % light transmittance of the sample?

3. What is the light absorbance of the sample?

4. What is the concentration (M) of the diluted sample?

5. What is the concentration (g/mL) of the diluted sample?

6. What is the concentration (g/mL) of the original sample?

7. What is the amount of lycopene (mg) in 1 serving?

You are measuring lycopene in samples of tomato sauce. You extract a 2.1 mL sample of tomato sauce 3X with 5 mL hexane. You pool the extracts and bring to a final volume of 25 mL with hexane. You then evaporate the extract under N2 and resolubilize to a final volume of 3 mL hexane. You then measure the sample at 502 nm on an ???old school a?? spectrophotometer that only measures intensity of the incident light (10, 158 units) and the light transmitted through the sample (I, 54 units), and has a path length of 0.94 cm. The molar absorptivity of lycopene at 502 nm is 1.72 A? 105 L a?cmol?1 cm?1 . The serving size of tomato sauce is 1 US ???legal ??cup. Lycopene MW=536.89 g/mol, formula=C40H56 1. What is the light transmittance of the sample? 2. What is the % light transmittance of the sample? 3. What is the light absorbance of the sample? 4. What is the concentration (A Mu M) of the diluted sample? 5. What is the concentration (A Mu g/mL) of the diluted sample? 6. What is the concentration (A mu g/mL) of the original sample? 7. What is the amount of lycopene (mg) in 1 serving?

Explanation / Answer

Incident light Io = 158 units

Transmitted light It = 54 units

1.

Incident light Io = 158 units

Transmitted light It = 54 units

Transmittance T = It/Io = 54/158 = 0.341

2. % light transmittance of the sample = 100 T = 34.1 %

   3. Absorbance A = log (Io / It )

                     = log (158/54) =

                     = log2.926 =

                        = 0.466

    4.

L

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.