Answer:
pH = 4.57
Explanation:
pH = pKa + log ([OAc⁺]/[HOAc])
Ka(HOAc) 1.8 x 10⁻⁵ => pKa = -log(1.8 x 10⁻⁵) = 4.74
[OAc⁻] = 0.20M
[HOAc] = 0.30M
pH = 4.74 + log([0.20]/[0.30]) = 4.47 + (-0.17) = 4.57
The rule is number your table 1 2. 3 4 5 6 7 0 the number of shells increase as you go further up as it indicates the number of electrons on the outer shell e.g Argon will have 3 electrons on its outer shell hope this helps if not its then tighttt
