A student found a 500 cm3 sample of vinegar. Knowing that vinegar is a solution of ethanoic acid (CH3COOH) and water, this student decided to take a 25.0 cm3 sample, dilute it with 25.0 cm3 of water and then react it with sodium hydroxide. The dilute sample required 37.0 cm3 of 0.850 mol dm–3 sodium hydroxide solution to react entirely with it via the following reaction: CH3COOH(aq) + NaOH(aq) → NaCH3COO(aq) + H2O(l)

Calculate the concentration of ethanoic acid in the original sample of vinegar.

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.