A 30.84ml volume of 0.128M NaOH is required to reach
thephenolphthalein endpoint in the titration of a 5.441g sample
ofvinegar. Calculate the Percent acetic acid in the vinegar.

Respuesta :

Answer:

Percent acetic acid in the vinegar is 4.35%.

Explanation:

[tex]Moles (n)=Molarity(M)\times Volume (L)[/tex]

Moles of NaOH = n

Volume of NaOH solution = 30.84 mL = 0.03084 L

Molarity of the NaOH  = 0.128 M

[tex]n=0.128 M\times 0.03084 L=0.003948 mol[/tex]

[tex]NaOH+CH_3COOH\rightarrow CH_3COONa^++H_2O[/tex]

According to reaction ,1 mole of NaOH reacts with 1 mol of acetic acid.

Then ,0.03948 mol of NaIOH will recat with:

[tex]\frac{1}{1}\times 0.003948 mol=0.003948 mol[/tex] of acetic acid.

Mass of 0.03948 moles of acetic acid = 0.003948 mol × 60 g/mol = 0.2368 g

Mass of vinegar solution = 5.441 g

Percent acetic acid in the vinegar :

[tex]=\frac{0.2368 g}{5.441 g}\times 100=4.35\%[/tex]