Question

Sebanyak 3,16 gram (CH3COO)2Ca (Mr=158) dilarutkan dalam air hingga volumenya 200 ml. Jika Ka CH3COOH=2.10^-5, pH larutan adalah.....
(pakai langkah penyelesaiannya please)

Answer 1

ANSWER ::::#



mol = massa/Mr
mol = 3,16/158
mol = 0,02 mol

M = mol/Vol
M = 0,02/0,2
M = 0,1 M

[H⁺] = √Ka • M

[H⁺] = √2 x 10⁻⁵ • 0,1

[H⁺] = √2 x 10⁻⁶

[H⁺] = 1,4 x 10⁻³

pH = -log [H⁺]

pH = -log [1,4 x 10⁻³]

pH = 3 - log 1,4