Lab on Determining hard water
Not sure if I answered this currently, not completely sure how to explain either.
If a student has a non-zero blank correction, but forgets to include that correction in his/her calculations:? a. Would his/her calculated [EDTA] be correct, too high, or too low? b. Would his/her calculated [Ca] in the unknown be correct, too high, or too low?
Not quite sure if my answers are right:
A. EDTA would be a too high
B. Calculate would be low
I don't know your procedure but you can answer the question by looking at the formula you used and where you have volume, substitute a larger number and see how that affects the answer.
Thanks
To determine whether the answers provided are correct, we need to understand the concept of a blank correction and how it affects the calculations.
In the context of determining hard water, a blank correction is used to account for any impurities or color in the reagents used in the analysis. By measuring the reagents without the water sample, any impurities in the reagents can be accounted for and subtracted from the final calculations.
Let's address each part of the question:
a. If a student has a non-zero blank correction but forgets to include that correction in their calculations, the calculated [EDTA] (Ethylenediaminetetraacetic acid) would be too high. This is because the blank correction is meant to account for any impurities or color that could overestimate the amount of EDTA present in the solution. Without subtracting the blank correction, the calculated concentration of EDTA would be higher than it should be.
b. Similarly, if the student forgets to include the blank correction in their calculations, the calculated [Ca] (Calcium) in the unknown solution would be too low. This is because the blank correction accounts for any impurities or color that could react with the EDTA and interfere with the calcium analysis. Without subtracting the blank correction, the calculated concentration of calcium would be underestimated.
To ensure accurate results, it is essential to include the blank correction in the calculations when determining hard water. It helps eliminate errors caused by impurities in the reagents, ensuring more reliable and precise results.