hitunglah ph campuran 100ml hcl 0,2 m dan 100 ml Nh4OH 0,2 m (kb = 1 . 10 pangkat -5)

100 mL HCl 0,2 M + 100 mL NH4OH 0,2 M
Kb = 1 × 10^-5

pH campuran ... ?

n HCl = M × V
n HCl = 0,2 × 100
n HCl = 20 mmol

n NH4OH = M × V
n NH4OH = 0,2 × 100
n NH4OH = 20 mmol

#Reaksi
..... HCl + NH4OH => NH4Cl + H2O
M : 20 ........ 20
R : 20 ........ 20
_____________---
S : --- .......... --- ............. 20 ....... 20

M = n/V total
M = 20/(100 + 100)
M = 20/200
M = 0,1

Garam NH4Cl bersifat asam.

[H^+] = √( Kw/Kb × M )
[H^+] = √( 10^-14/10^-5 × 0,1 )
[H^+] = √( 10^-9 × 0,1 )
[H^+] = √( 10^-9 × 10^-1 )
[H^+] = √( 10^-10 )
[H^+] = 10^-5

pH = - log [H^+]
pH = - log 10^-5
pH = 5