Question

Suatu larutan denga. pH = x diencerkan 1000 kali sehingga menjadi pH = 5. Harga x adalah...
A. 2
B. 3
C.4
D.5
E.6

Tolong bantu ya... thanks :)

Answer 1

V1 M1 = V2 M2
1 M1 = 1000 10^-5
M1 = 10^-2 M

x = - log H+ = - log 10^- 2= 2 B

Answer 2

PH = 5, maka :
[H⁺] = 10⁻⁵
M = 10⁻⁵ Molar

Pakai rumus pengenceran :
M1 x V₁ = M₂ x V₂
10⁻⁵ x 1000 = M₂ x 1
M₂ = 0,01

[H⁺] = Molaritas x Valensi
[H⁺] = 0,01 x 1
[H⁺] = 10⁻²

pH = -log H⁺]
pH = -log [10⁻²]
pH = 2

Jadi, harga x adalah 2 (Jawaban A)