Math Problem Statement

Suppose you measure the absorbance of a yellow dye solution in a 1.00 cm cuvette (b=1.00 cm).

The absorbance of the solution at 427 nm is 0.30 . If the molar absorptivity of yellow dye at 427 nm is 27400 M–1cm–1, what is the concentration of the solution in M?

Solution

To calculate the concentration of the solution using the given data, we can use Beer-Lambert's Law, which is:

A=εbcA = \varepsilon \cdot b \cdot c

Where:

  • AA is the absorbance (0.30),
  • ε\varepsilon is the molar absorptivity (27,400 M-1^\text{-1}cm-1^\text{-1}),
  • bb is the path length (1.00 cm),
  • cc is the concentration in molarity (M).

We can rearrange this formula to solve for the concentration cc:

c=Aεbc = \frac{A}{\varepsilon \cdot b}

Now we plug in the values:

c=0.3027400M1cm11.00cmc = \frac{0.30}{27400 \, \text{M}^{-1} \, \text{cm}^{-1} \cdot 1.00 \, \text{cm}}

Let me calculate that for you.The concentration of the yellow dye solution is approximately 1.09×105M1.09 \times 10^{-5} \, \text{M}.

Would you like more details or have any questions about the calculation? Here are five related questions:

  1. What happens to the concentration if the absorbance increases?
  2. How does the molar absorptivity affect the sensitivity of absorbance measurements?
  3. Can Beer-Lambert’s law be applied for highly concentrated solutions?
  4. What are the limitations of the Beer-Lambert law?
  5. How would you measure the absorbance of a different wavelength for the same dye?

Tip: For very dilute solutions, absorbance values might be too small to measure accurately, so ensuring a sufficiently concentrated sample is key.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Chemistry
Beer-Lambert Law
Algebra

Formulas

A = ε × b × c
c = A / (ε × b)

Theorems

Beer-Lambert Law

Suitable Grade Level

Undergraduate (General Chemistry)