Answer:
7.7%
Explanation:
the balanced equation for the neutralization reaction is:
CH3COOH+NaOH→CH3COONa+H2O
from the balanced equation above,the mole ratio of CH3COOH to NaOH is 1:1
no of mole of CH3COOH= no of mole of NaOH
no of mole of NaOH= concentration(M) × Volume(L)
=0.2 M× 0.02556=0.005112 mol
since, no of mole of CH3COOH= no of mole of NaOH
no of mole of CH3COOH=0.005112 mol
However ,no of mole =mass/molar mass
molar mass of CH3COOH=60.052g/mol
mass of CH3COOH=0.005112×60.052
=0.307g
percentage by mass of acetic acid in the vinegar=0.307/4
=0.07675×100%
=7.675%
