Answer to Question #93584 in General Chemistry for Miguel Lacsson

Question

4.
A In determining the percent acetic acid in vinegar, the mass of each vinegar sample is measured rather than the volume. Explain.
B. If the vinegar is measured volumetrically, (e.g. pipet) what additional piece of data would be needed to complete the calculation for the experiment?

5. The buret is filled NaOH titrant and the initial volume reading is immediately recorded without waiting the recommended 10 t0 15 seconds. However, the 10 to 15 second time lapse does occur before the reading is made. Does this technique error result in an increase,a decrease, or have no effect on the reported percent acetic acid in the vinegar? Explain.

6.The endpoint of the titration is overshot! Does this technique error in an increase, a decrease, or have no effect on the reported percent acetic acid in the vinegar. Explain.

Answer 1

A) As a rule, in the analysis of vinegar, the mass fraction of acetic acid is determined. And to find the mass fraction of the component you need to know the mass of the mixture
B) It is inconvenient to use volume in this situation. Since to find the mass by volume, it will be necessary to measure the density, and additional measurements will introduce additional errors.
5) Before removing the initial value, you must wait for all drops to drip. If you do not do this, the result may be underestimated.
6) This error will lead to an overestimation of readings