Page 79 - KIMIA SMA KELAS XI BERBASIS PjBl

6. a.
7.
Diketahui M. HCl = 0,1 M V. HCl = 20 mL
V. Sampel = 15 mL Ditanya ; M Sampel .... ?
Diketahui data hasil percobaan M NaOH = 0,1 M
Ditanya ; M HCl .... ?
Jawab
Menghitung rata-rata volume HCl
𝑉 𝐻𝐶𝑙 = 23,4+24+23,8+24,2+25 = 120,4 = 24,08 55
Menghitung M HCl
M1 × V1 = M2 × V2
0,1 × 25 = M2 × 24,08
𝑀2= 2,5 =0,10𝑀 24,08
b. Diketahui : M = 0,10 M Ditanya : pH ...?
Jawab :
Jawab
[𝐻+] = 𝑀 × 𝑎 [𝐻+] = 0,10 × 1 [𝐻+]=0,10= 1×10−1 𝑝𝐻 = −𝐿𝑜𝑔[𝐻+]
𝑝𝐻 = −𝐿𝑜𝑔[10−1]
𝑝𝐻 = 1
M1 × V1 = M2 × V2
0,1 × 20 = M2 × 15
𝑀2= 2 =0,133𝑀 15
Kimia Kelas XI SMA/MA
69