Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

REPORT SHEET EXPERIMENT Titration Curves of 26 Poly protic Acids B. Standardizat

ID: 518179 • Letter: R

Question

REPORT SHEET EXPERIMENT Titration Curves of 26 Poly protic Acids B. Standardization of Sodium Hydroxide (Naoh) solution Trial Mass of bottle +KHP 7.4 L2 50s29 Mass of bottle Mass of KHP 7.DDI used 56 Final buret reading 1850mL Initial buret reading ML. 226 bo mL of NaOH used Molarity of NaOH mai 22 Average molarity (show calculations) Standard deviation (show calculations) C. Determination of the Acid Dissociation Constants and the Molarity of the Unknown Acid Trial 3 Trial I Trial 2 2s Volume of unknown acid Molarity of NaOH from above mL of NaoH at eq. point I mL of NaOH at eq point 2 Molarity of unknown acid Copyright 2012 Pearson Education, Inc.

Explanation / Answer

moles of NaOH = moles of KHP

Moles of KHP= mass of KHP/molar mass = 0.448/204.22 = 0.00219 mol

moles of NaOH = 0.00219 mol

volume = 18.50 ml = 0.01850 L

molarity of NaOH = moles/volume = 0.00219/0.01850 = 0.118 M

Similarly for trial 2: 0.150 M

trial 3: 0.192 M

average = (0.118+0.150+0.192)/3 = 0.153 M

Standard deviation: [(0.153-0.118)2 + (0.153-0.150)2 + (0.153-0.192)2]/3

= (0.01225+0.000009+0.001521)/3 = 0.0046