What effect would be on the normality of unknown acid? Explain why.
a) if NaOH solution is pipetted into a conical flask containing some distilled water
b) if an air bubble is out from the burette
c) if too much acid is ran out during both titrations although the volumes of acid agreed
with each other
a) Molarity of the NaOH solution would be lower then expected, causing the molarity of the unknown acid calculated to be lower.
b) This would cause you to calculate more volume of the base then actually added. This will cause an increase in the molarity calculated for the unknown acid *** See note at the end.
c) This will cause an increase in the molarity of the acid since the volume of the NaOH will increase.
** See note at the end.
Use the following relationships to reason explanations.
Molarity=moles/volume
M1V1=M2V2
Where
M1=molarity of the acid
V1=volume of the acid
M2=molarity of the base
and
V2=volume of the base
*** I am interpreting this question as an air bubble being seen in the buret. If there is no air bubble in the buret then the results shouldn't be effected.
** I am interpreting this question as using more acid then anticipated.
To determine the effect on the normality of an unknown acid in the given scenarios, let's consider each situation individually:
a) If NaOH solution is pipetted into a conical flask containing some distilled water:
In this case, if the NaOH solution is added to the conical flask containing distilled water, there is no direct effect on the normality of the unknown acid. The normality of an acid or base is determined by its chemical composition and concentration, and adding the NaOH solution to water does not directly alter the normality of the acid being tested.
b) If an air bubble is removed from the burette:
When conducting a titration, an air bubble in the burette can cause inaccuracies in volume measurements. If the air bubble is not considered and accounted for, it can lead to a higher volume being measured, which affects the calculated normality of the acid. Therefore, in this case, removing the air bubble from the burette is crucial to get an accurate measurement and determine the correct normality of the unknown acid.
c) If too much acid runs during both titrations, although the volumes of acid agreed with each other:
If too much acid runs during multiple titrations, it indicates a potential error in the measurement or handling of the acid. This situation can affect the accurate determination of normality. Titrations rely on precise volume measurements, so if there is excessive acid running out, it means more acid is being used than intended, leading to an overestimation of concentration. Consequently, the normality determined would be higher than the actual value.
In summary, the normality of an unknown acid is not directly affected by adding NaOH solution to water. However, it can be affected by the presence of air bubbles in the burette, which can cause volume measurement errors and impact the calculated normality. Similarly, if too much acid runs out during titrations, it can lead to an overestimation of normality due to excess acid being used. Therefore, it is crucial to ensure accurate volume measurements and prevent errors in order to obtain reliable normality values.