Page 47 - Ebook Interaktif Asam Basa Berkonteks Green Chemistry dan Socio Scientific Issues (SSI)

Maka:

[H⁺][Se²⁻]
Ka₂ =
[HSe⁻]

(0,0072 + x)(x)
1,0 x 10⁻¹¹ = diasumsikan 0,0072 + x ≈ 0,0072 dan 0,0072 - x ≈ 0,0072
(0,0072 - x)

(0,0072)(x)
1,0 x 10⁻¹¹ =
(0,0072)

x = 1,0 x 10⁻¹¹ M

Sehingga,
[H₂Se] = (0,40 - x) = (0,40 - 0,0072) = 0,39 M
[HSe⁻] = (0,0072 - x) = 0,0072 M atau 7,2 x 10⁻³ M
[H⁺] = (0,0072 + x) = 0,0072 M atau 7,2 x 10⁻³ M
[Se²⁻] = 1,0 x 10⁻¹¹ M

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