-
Lampiran Perhitungan
1. Konsentrasi pengenceran larutan
M1 = konsentrasi awal asam asetat atau asam fosfat
V1 = volume awal asam asetat atau asam fosfat
M2 = konsentrasi akhir asam asetat atau asam fosfat
V2 = volume akhir asam asetat atau asam fosfat
M1 x V1 = M2 x V2
0.1 M x 20 mL = M2 x 100 mL
M2 = 0.1 M x 20 mL
100 mL
M2 = 0.02 M
2. Volume rata-rata
a. Asam asetat
V = V1+V2+V3
n
= 9.6453+9.2713+9.7949
3
= .
= 9.5795 mL
b. Asam Fosfat
V = V1+V2+V3
n
= 35.8253 +35.4139 +43.6793
3
= 114.9162
= 38.3054 mL
3. Konsentrasi larutan setelah titrasi
a. Asam asetat
M1 x V1 = M2 x V2
0.02 M x 25 mL = M2 x 9.5705 mL
M2 = 0.02 M x 25 mL
9.5705 mL
M2 = 0.05 M
b. Asam Fosfat
M1 x V1 = M2 x V2
0.02 M x 25 mL = M2 x 38.3054 mL
M2 = 0.02 M x 25 mL
38.3054 mL
M2 = 0.013 M
-
4. Ka Asam asetat
a. Titrasi pertama
CH3COOH H+ + CH3COO
-
Volume ekuivalen = 6.65 mL
Volume ekuivalen = 3.325 mL
pH volume ekuivalen = 4.8
pK = pH
-log Ka = - log [H+]
Ka = [H+]
pH = - log [H+]
4.8 = - log [H+]
[H+] = 1,6 x 10
-5
Ka = 1,6 x 10-5
b. Titrasi kedua
CH3COOH H+ + CH3COO
-
Volume ekuivalen = 6 mL
Volume ekuivalen = 3 mL
pH volume ekuivalen = 4.8
pK = pH
-log Ka = - log [H+]
Ka = [H+]
pH = - log [H+]
4.8 = - log [H+]
[H+] = 1,6 x 10
-5
Ka = 1,6 x 10-5
y = 1.074x + 1.780R = 0.862
0
2
4
6
8
10
12
14
0 5 10 15
pH
Volume
Grafik Asam Asetat 1
Series1
Linear (Series1)
-
c. Titrasi ketiga
CH3COOH H+ + CH3COO
-
Volume ekuivalen = 6.43 mL
Volume ekuivalen = 3.2 mL
pH volume ekuivalen = 4.9
pK = pH
-log Ka = - log [H+]
Ka = [H+]
pH = - log [H+]
4.9 = - log [H+]
[H+] = 1,2 x 10
-5
Ka = 1,2 x 10-5
5. Ka1 Asam Fosfat
H3PO4 H+ + H2PO4
-
y = 1.137x + 2.062R = 0.870
0
2
4
6
8
10
12
14
0 5 10
pH
Volume
Grafik Asam Asetat 2
Series1
Linear (Series1)
y = 1.078x + 1.997R = 0.867
0
2
4
6
8
10
12
14
0 5 10 15
pH
Volume
Grafik AsamAsetat 3
Series1
Linear (Series1)
-
Ka = H+ [H2PO4
]
[H3PO4]
H2PO4- H+ + HPO4
2-
Ka = H+ [HPO4
2]
[H2PO4]
HPO42- H+ + PO4
3-
Ka = H+ [PO4
3]
[HPO42]
nilai pK = pH log GARAM
ASAM
[garam]=[asam]
pK = pH
a. Titrasi pertama
Volume ekuivalen = 12.67 ml
Volume ekuivalen = 6.335 mL
pH volume ekuivalen = 2.4
pK = pH
-log Ka = - log [H+]
Ka = [H+]
pH = - log [H+]
2.4 = - log [H+]
Ka1 = 4 x 10-3
b. Titrasi kedua
Volume ekuivalen = 11.33 ml
Volume ekuivalen = 5.6 ml
pH volume ekuivalen = 2.4
y = 0.336x + 0.865R = 0.957
0
2
4
6
8
10
12
14
0 10 20 30 40
pH
Volume
Grafik Asam Fosfat 1
Series1
Linear (Series1)
-
pK = pH
-log Ka = - log [H+]
Ka = [H+]
pH = - log [H+]
2.4 = - log [H+]
Ka1 = 4 x 10-3
c. Titrasi ketiga
Volume ekuivalen = 15.33 ml
Volume ekuivalen = 7.6 mL
pH volume ekuivalen = 2.4
pK = pH
-log Ka = - log [H+]
Ka = [H+]
pH = - log [H+]
2.4 = - log [H+]
Ka1 = 4 x 10-3
y = 0.341x + 1.046R = 0.960
0
5
10
15
0 10 20 30 40
pH
Volume
Grafik Asam Fosfat 2
Series1
Linear (Series1)
y = 0.272x + 0.813R = 0.956
0
5
10
15
0 20 40 60
pH
Volume
Grafik Asam Fosfat 3
Series1
Linear (Series1)
-
6. Ka2 Asam Fosfat
a. Titrasi pertama
Volume ekuivalen = 12.67 ml
Volume 3/2 ekuivalen = 19.005 mL
pH saat volume 3/2 ekuivalen = 7.7
pK = pH
-log Ka = - log [H+]
Ka = [H+]
pH = - log [H+]
7.7 = - log [H+]
Ka2 = 2 x 10-8
b. Titrasi kedua
Volume ekuivalen = 11.33 ml
Volume 3/2 ekuivalen = 16.995 mL
pH volume 3/2 ekuivalen = 7.8
pK = pH
-log Ka = - log [H+]
Ka = [H+]
pH = - log [H+]
7.8 = - log [H+]
Ka2 = 1,6 x 10-8
c. Titrasi ketiga
Volume ekuivalen = 15.33 ml
Volume 3/2 ekuivalen = 22.995 mL
pH volume 3/2 ekuivalen = 7.7
pK = pH
-log Ka = - log [H+]
Ka = [H+]
pH = - log [H+]
7.7 = - log [H+]
Ka2 = 2 x 10-8
