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Tolong kerjakan nomee 1 dan 2, dengan cara

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Tolong kerjakan nomee 1 dan 2, dengan cara Memenuhi ketentuan dapet jawaban terbaik

1 Jawaban

  • pH masing-masing larutan sebelum bercampur

    CH3COOH 0,1 M (Ka = 10–5)

    CH3COOH ⇔ H+ + CH3COO–

    [H+ ] = \sqrt{Ka x M}

    [H+ ] = \sqrt{ 10^{-6} }

    [H+ ] = 10^{-3} M

    pH = - log [H+ ]

    = - log 10-3

    = 3



    NaOH 0,1 M

    NaOH → Na+ + OH–

    [OH- ] = x · [OH]

    = 1 · 0,1

    = 0,1 M

    pOH = - log [OH- ]

    = - log 0,1

    = - log 10-1

    = 1

    pH = 14 – pOH

    = 14 – 1

    = 13



    pH setelah pencampuran

    Reaksi CH3COOH + NaOH → CH3COONa + H2O

    Mol mula-mula 20 mmol 10 mmol

    Mol reaksi 10 mmol 10 mmol 10 mmol 10 mmol

    -------------------------------------------------------------------------------------------------

    Mol sisa 10 mmol - 10 mmol 10 mmol

    (dalam 200 ml larutan)

    [CH3COONa] = \frac{mol CH3COONa}{volume} \\ =\frac{10}{200}

    = 0,05M

    [CH3COOH] = \frac{(mol CH3COOH)}{volume} \\ =\frac{10}{200}

    = 0,05M

    H+ = Ka. \frac{CH3COOH}{CH3COONa}

    H+ = 10-5 \frac{0,05}{0,05}

    H+ = 10^{-5}

    pH = -log [H+]

    = -log 10-5

    = 5

    Jadi, pH setelah pencampuran adalah 5