Indicate how each of the following would affect the value of the absorbance (too
ID: 918443 • Letter: I
Question
Indicate how each of the following would affect the value of the absorbance (too low, too high, no effect) of the indicated solution. Explain your answers. A student prepares solution A as instructed and pours it into a wet beaker. A student rinses the 10.00 ml pipet only with D1 water in the preparation of D (but does the rest of the procedure as instructed). 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).Explanation / Answer
a. If we are considering the measurement of absrobance of solution A , and if we have poured it into a wet beaker, then it means that we have diluted the solution. The presence of water in beaker will dilute the solution A poured in it.
From Beer Lambert's law, the absrobance is directly proportional to concentration of solution, so due to decrease in concentration the value of absrobance will be low.
b. If we are measuring the absrobance of solution D itself then the concentration of solution D will again be low as there is distilled water in the pipette which will dilute the solution. Hence the absrobance of solution D will be less.
c. If we are measuring the absrobance of solution B itselft, then as we have filled less amount of water in the volumetric flask (lower meniscus than the mark) so it will be more concentrated as per our expectations.
Due to more concentration of solution B , the absrobance value will be high for solution B.