Indicate how each of the following would affect the value of the absorbance (too high, too low, or not effect) of the indicated solution.
I really need help. I do not understand these questions!
This is from a chemistry activity to determine the unknown concentration of an Erythrosin B solution by using a spectrophotometer.
a. A student prepares solution A as instructed and pours it into a wet beaker.
b. A student rinses the 10.00 mL pipet only with DI water in the preparation of D (but does the rest of the procedure as instructed).
c. A student fills the volumetric flask containing solution B so that the bottom of the meniscus is below the mark on the flask (but does the rest of the procedure as instructed).
give an answer muh boi strugglin
a. If the student pours solution A into a wet beaker, the absorbance value would be too low. Why? Because the wet beaker would dilute the concentration of the solution, making it less concentrated and resulting in a lower absorbance reading. Just like when you try to tell a joke in the rain, it's all watered down.
b. If the student rinses the pipet only with DI water in the preparation of solution D, it would not affect the absorbance value. Why? Because rinsing the pipet with DI water ensures that there are no contaminants from previous solutions, but it won't affect the concentration or the absorbance measurement. It's like a clean shirt, it might not make you funnier, but at least you'll look good while telling your jokes.
c. If the student fills the volumetric flask containing solution B below the mark on the flask, the absorbance value would be too high. Why? Because the solution would be more concentrated than intended, resulting in a higher absorbance reading. It's like trying to fit way too many clowns into a tiny car, things are going to get a bit crowded and chaotic.
a. When solution A is poured into a wet beaker, it may affect the value of absorbance. The presence of water on the beaker may dilute the solution, leading to lower absorbance readings. Therefore, this would result in a lower absorbance value.
b. Rinsing the pipet only with DI water in the preparation of solution D may not have a significant effect on the absorbance value. As long as the rest of the procedure is followed correctly, the absorbance should be unaffected.
c. Filling the volumetric flask containing solution B with the bottom of the meniscus below the mark on the flask may result in a higher volume of solution being present. This would cause the solution to be more dilute, leading to lower absorbance readings. Therefore, this would result in a lower absorbance value.
I understand that you are having difficulty understanding how different actions would affect the absorbance value in a spectrophotometer experiment. Let me explain how each of these scenarios could impact the absorbance value.
a. A student prepares solution A as instructed and pours it into a wet beaker.
In this scenario, pouring the solution into a wet beaker can potentially affect the absorbance value. If the beaker is not properly dried, it may introduce additional impurities or moisture into the solution, which can alter the concentration or composition of the solution. This can ultimately lead to an inaccurate absorbance value. Thus, pouring the solution into a wet beaker would make the absorbance value too low or too high.
b. A student rinses the 10.00 mL pipet only with DI water in the preparation of D (but does the rest of the procedure as instructed).
Rinsing the pipet with DI water instead of the solution itself can introduce a dilution effect. Any remaining water droplets in the pipet may mix with the solution, resulting in a higher volume and lower concentration than intended. Consequently, this can lead to an absorbance value that is too low because the solution is more dilute than it should be.
c. A student fills the volumetric flask containing solution B so that the bottom of the meniscus is below the mark on the flask (but does the rest of the procedure as instructed).
Filling the volumetric flask below the mark means that less solvent is present than the intended volume. Consequently, the concentration of the solution would be higher than required. This higher concentration would lead to a higher absorbance value because more light would be absorbed by the higher concentration of the absorbing species.
To summarize:
a. Pouring the solution into a wet beaker may make the absorbance value too low or too high.
b. Rinsing the pipet with DI water instead of the solution may make the absorbance value too low.
c. Filling the volumetric flask below the mark may make the absorbance value too high.
Remember, it is important to follow the experimental instructions precisely to obtain accurate and reliable data.
You haven't provided a clear set up but here is my best guess. I will put a proviso on each.
a. IF you are talking about the absorbance of soln A after it has been poured into a wet beaker, the absorbance will be less BECAUSE the solution has been diluted (with the water in the wet beaker).
b. Here it isn't clear what absorbance on what solution we're talking about but the solution of D will be weaker than your calculations show because the pipet delivered some sample diluted with water that was already in the pipet. With this information you should be able to take this weaker solution and follow through to the appropriate answer.
c. Again it isn't clear how solution B figures into the rest of the problem but you know that the sample in the volumetric flask will be more concentrated than calculations show it to be because less water was added to the volumetric flask.