We did an Vitamin C Titration experiment. We got 2 tablets of Vitamin C and crus

Question

We did an Vitamin C Titration experiment. We got 2 tablets of Vitamin C and crushed them up and seperated into 3 flasks. We then added 50 mL of distilled water and added 3 drops of phenolphthalein to each flask. Then we started titrating.

Flask 1: 0.40g vitamin c and dispensed 18.94 mL of NaOH 0.3260g of vitamin c in this sample after reaction

Flask 2: 0.45g vitamin c and dispensed 21.18mL of NaOH 0.3646g vitamin c in this sample after reaction

Flask 3: 0.42g vitamin c and dispensed 19.18 mL of NaOH 0.3301g vitamin c in sample after reaction

My questions are:

1. how do I calculate the mass of vitamin C in one full tablet?

2. how do I calculate the percent error of my work?

Thanks in advance

Explanation / Answer

1 mole of ascorbic acid (vitamin C tablet) reacts with 1 mole of NaOH

So, mass of asocrbic acid in three flasks

Flask 1 = 0.09773 M x 0.01894 L x 176.12 g/mol = 0.3260 g

Flask 2 = 0.09773 M x 0.02118 L x 176.12 g/mol = 0.3645 g

Flask 3 = 0.09773 M x 0.01918 L x 176.12 g/mol = 0.3301 g

Total mass of ascorbic acid in two tablets = 1.0206 g

1. mass of ascorbic acid (vitamin C) in one tablet = 0.5103 g

2. Actual mass of 1 vitamin C tablet = (0.40 + 0.45 + 0.42)/2 = 0.635 g

Percent error = [(0.635 - 0.5103)/0.635] x 100 = 19.64%

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.