Australia's Science Forum

Hi all,
Can anyone give me hints/tips or a new experiment for this?

I have tried pouring 150ml of 1.0M Dextrose soln in a bottle and added 3M NaOH. Finally when I add 4 - 5 ml of Indigo Carmine (200mG in 100ml distilled water), the bluey green colour does not last long and shaking doesn't bring it back. Should I be using a stronger soln of something than what I am?

Regards,
Lou P.

Hi loopy,

Try using 0.1M Dextrose solution as I seem to think that this solution is too strong hence the reason for the quick change and no reverse reaction.

As a guide: Dissolve 9 G of dextrose in 500 mL of distilled water and stir until all have dissolved. OR simply dilute the solution 1/10th the strength (50mL of 1.0M dextrose in 500mL of Distilled Water this will give 0.1M dextrose solution).

(Reversing Oxidation and Reduction reactions can be quite temperamental when it comes to solution concentrations).

I hope this has fixed your problem.

Robb..........