Question

Calculate the approximate volume of the vinegar sample needed for the analyses Mass of flask (g) Mass of flask + vinegar (g) Mass of vinegar (g) Buret reading of NaOH_2 initial (mL) Buret reading of NaOH, final (mL) Volume of NaOH used (mL) Molar concentration of NaOH (mol/L) Moles of NaOH added (mol) Moles of CH-3COOH in vinegar (mol) Percent by mass of CH_3COOH in vinegar(%) Average percent by mass of CH_3COOH in vinegar (%)
Please help with calculations and solutions written out. Thank you!

Answer 1

From the data

                                                 Trial 1 (g)                      Trial 2 (g)

A. 3. mass of vinegar =               3.352                              3.351

B. analysis

3. Volume of NaOH =               19.8 ml                             19.5 ml

4. molarity of NaOH = 0.1 M

5. moles of NaOH = 0.1 x 19.8 = 1.98 mmol                   1.95 mmol

6. moles of CH3COOH =             1.98 mmol                   1.95 mmol

7. mass of CH3COOH = 1.98 x 60.05 = 0.119 g             0.117 g

Average CH3COOH = 0.118 g

8. Percent CH3COOH in vinegar = 0.118 x 100/3.352 = 3.52%

9. Average percent by mass = 3.52%