Electrolyte solutionsHigh frequency

• A.When $20\ \mathrm{mL}$ of $\mathrm{NaOH}$ solution has been added, the solution is neutral
• B.When the solution reaches $\mathrm{pH}=7$, exactly $20\ \mathrm{mL}$ of $\mathrm{NaOH}$ solution has been added
• C.When $40\ \mathrm{mL}$ of $\mathrm{NaOH}$ solution has been added, $c(\mathrm{Na^+})=c(\mathrm{CH_3COO^-})+c(\mathrm{CH_3COOH})$
• D.When the solution reaches $\mathrm{pH}=7$, $c(\mathrm{Na^+})=c(\mathrm{CH_3COO^-})$

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