Measuring Range

0.002 to 0.004%

0.004 to 0.02%

0.02 to 1.5%

1.5 to 4.5%

Number of Pump Strokes

4

2

1

1/2

Correction Factor

1/9

1/5

1

3

Sampling Time

3 minutes per pump stroke

Detecting Limit

0.0004% (n=4)

Color Change

Pink Pale Blue

Reaction Principle

Isopropyl alcohol reduces potassium dichromate to
form chromic sulfate, which is pale blue in color
CH₃OH + Cr⁶⁺ + H₂SO₄ Cr³⁺

15% (for 0.02 to 0.5 %), 10% (for 0.5 to 1.5 %)