Question

Questions (Pay attention to units and significant figures for the calculations sted molarity of NaOH 1. For each of the following circumstances indicate whether the calculated molarity of would be lower, higher or unaffected. Explain your answer in each case a. The inside of the pipet used to transfer the standard HCl solution was wet with water. b. You added 40 mL of water to the titration flask rather than 25 mL. c. The buret, wet with water, was not rinsed with NaOH solution before filling the buret with NaOH solution. d. Five (5) drops of phenolphthalein were added to the solution to be titrated rather than three (3) drops. Page 2 of 4 18 - Report

Answer 1

(HCI) Molarity of Acid (monobrotic) x volume of Fl. Calculated molarity of ala OH - auct volume of Nach used a). b). This will dilute the Hel sol", and a lower volume of NaOH will be used for neutralisation of Hel. And this if lower volume of NaOH is used then calculated molarity of Mact will be higher. This again will dilute Hel in titration flask and again less. volume of Nooh will se used for neutralisation. And again calculated molarity will se higher. This will cause dilution of Naoh and thus more volume of Nach will be used for neutralisation and this in this case calculated molarity will be lower. Volume of indicator (phenolphthalein, don't affects the neutralisation volume of alaot. This in this case, the calculated molarity of Naolt will remain unaffected. c). d).