Reaction Medium

Volume of thiosulfate (0.01 N) solution, mL.

Recovery, %

HCl (0.1 M)

5.4

54.0

water

6.4

64.0

Acetate buffer (pH, 3.6)

7.1

71.0

Acetate buffer (pH, 3.8)

7.9

79.0

Acetate buffer (pH, 4.0)

8.2

82.0

Acetate buffer (pH, 4.2)

8.4

84.0

Acetate buffer (pH, 4.4)

8.7

87.0

Acetate buffer (pH, 4.6)

9.1

91.0

Acetate buffer (pH, 5.0)

9.7

97.0

Acetate buffer (pH, 5.2)

10.0

100

Acetate buffer (pH, 5.4)

9.8

98.0

Acetate buffer (pH, 5.6)

9.6

96.0

Acetate buffer (pH, 7.0)

8.6

86.0

Acetate buffer (pH, 8.5)

6.9

69.0

Acetate buffer (pH, 10.0)

5.7

57.0