Question

Question : The accuracy of this experiment depends on good technique. Would the following techinque errors result in an erroneously high or an erroneously low calculated molarity of an NaOH solution? Breifly explain your reasoning for each answer. a) The KHP you used had not been dried. b) When filling the buret with NaOH you left a air bubble in the buret tip.The bubble was released during your first KHP titration. c) After completeing the titration you noticed droplets of titrant clinging to the inner wall of the buret.

Answer 1

Molarity = Mol/V

mol of NaOH!

then

a) The KHP you used had not been dried.

if not dried, then we will assume there is "more" acid, than actual acid.. we will then relate to "much" acid. The calculation involves relating moles of acid = moles of base, therefore, you will expect lower concnetration

b)When filling the buret with NaOH you left a air bubble in the buret tip.The bubble was released during your first KHP titration.

The air bubble will "increase" the NaOh amount needed... since we use less volume, you will expect a lower concnetration of NaOH

c) After completeing the titration you noticed droplets of titrant clinging to the inner wall of the buret.

The "titrant2 is NaOH, it didn't reacted so you spend much more that required, the concnetration will be less since you will calculate, wrongly, that you needed x volume when in reallity, the x quantity is too high