3.3 Redox Standards & Checking

To confirm meter accuracy 475mV, 263mV and 83mV standards are available. Redox standard 475mV is a ready prepared solution. Redox standards at 263 and 86mV can be prepared as follows:

Redox Standard - 263mV @ 25oC

1. Take a 20ml sample of Kittiwake pH 4 Buffer Solution. 
2. Add a small quantity (approx 0.05-0.1g) of Quinhydrone Powder.
3. Shake vigerously to mix.
(Very little quinhydrone will dissolve, so the solution will end up grey/black).
4. The Redox Standard is now ready for use.
5. Discard after use.

Redox Standard 86mV @ 25oC

1. Take a 20ml sample of Kittiwake pH 7 Buffer solution.
2. Add a small quantity (approx 0.05-0.1g) of Quinhydrone Powder.
3. Shake vigerously to mix.
(Very little quinhydrone will dissolve, so the solution will end up grey/black).
4. The Redox Standard is now ready for use.
5. Discard after use.

Order Information

AS-K24893-KW 475mV Redox Standard 500ml
AS-K20011-KW pH 4 Buffer Solution 500ml
AS-K20008-KW pH 7 Buffer Solution 500ml
AS-K24891-KW Quinhydrone Powder 10g