The pKa value of ethanoic acid CH3COOH , also known as acetic acid, is approximately 4.76. This value represents the acidity of the ethanoic acid, with lower pKa values indicating stronger acids.If the pH of the solution is 5, it means the solution is slightly acidic, as the pH scale ranges from 0 to 14, with 7 being neutral. Since the pH of the solution 5 is greater than the pKa of ethanoic acid 4.76 , it indicates that the solution contains more of the conjugate base CH3COO- than the acid CH3COOH . In other words, the ethanoic acid is not fully protonated in the solution, and the solution has a higher concentration of acetate ions CH3COO- than ethanoic acid molecules CH3COOH .The difference between the pH and pKa values can be used to determine the ratio of the concentrations of the conjugate base and the acid using the Henderson-Hasselbalch equation:pH = pKa + log [A-]/[HA] Where [A-] is the concentration of the conjugate base CH3COO- and [HA] is the concentration of the acid CH3COOH . In this case:5 = 4.76 + log [CH3COO-]/[CH3COOH] Solving for the ratio of [CH3COO-] to [CH3COOH], we get:log [CH3COO-]/[CH3COOH] = 5 - 4.76 = 0.24Taking the antilog:[CH3COO-]/[CH3COOH] = 10^0.24 1.74This means that in a solution with a pH of 5, the concentration of acetate ions CH3COO- is approximately 1.74 times greater than the concentration of ethanoic acid molecules CH3COOH .