Finding Beer's Law Slope: Homework Help

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In summary, the speaker has created a graph of Absorbance vs. Concentration using data from a lab and is now attempting to find the slope of the curve. They used Excel to get a trendline of y = 228.19x + .0369 and are questioning if this is the correct slope to use for Beer's Law. They are seeking quick feedback and confirmation.
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Homework Statement


I made a graph of Absorbance vs. Concentration from data I got in the lab.
I graphed it and now am trying to figure out how to find the slope of the curve.
It's supposed to be a Beer's Law calibration curve.



Homework Equations





The Attempt at a Solution


I used Excel and got y = 228.19x + .0369 as the trendline.
Would 228.19 be the Beer's Law slope I need to use to find the concentrations of other absorbances later in the lab? It seems too high, but I really need feedback fast, please. Thank you.
 
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Yes, it's the slope. Make sure you have chosen x and y correctly, though.
 

What is Beer's Law?

Beer's Law, also known as the Beer-Lambert Law, is a scientific principle that describes the relationship between the concentration of a solution and the amount of light it absorbs. It states that the absorbance of a solution is directly proportional to its concentration and the length of the path the light travels through the solution.

Why is it important to find Beer's Law slope?

Finding the slope of Beer's Law allows us to determine the concentration of a solution by measuring its absorbance. This is important in various fields such as chemistry, biochemistry, and environmental science, where accurately measuring the concentration of a solution is crucial for experiments and analyses.

How do I find the slope of Beer's Law?

The slope of Beer's Law can be found by plotting a graph of absorbance versus concentration for a series of known solutions and then calculating the slope of the best-fit line. Alternatively, it can also be calculated using the formula: slope = absorbance / concentration.

What factors can affect the slope of Beer's Law?

The slope of Beer's Law can be affected by several factors such as the type of solvent used, the wavelength of light used, and the temperature and pressure of the solution. It is important to keep these factors constant when determining the slope to ensure accurate results.

Can I use Beer's Law for all types of solutions?

No, Beer's Law is only applicable to solutions that follow the Beer-Lambert Law, which means that the concentration of the solution is directly proportional to its absorbance. This is usually true for dilute solutions, but for concentrated solutions or solutions containing colored impurities, other methods may need to be used.

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