ferroxyl indicator dissolving Agar

Afternoon all. I've been asked to make a ferroxyl indicator gel with the following

Potassium Hexacyanoferrate
Phenolpthalein indicator
Potassium Nitrate
Agar

I've made the solution but the method suggest to sit it on a steam bath so the Agar dissolves. We haven't got a steam bath but a water bath or the microwave. I usually dissolve Agar in the microwave when we do microbiology. Wasn't sure if this was a good idea being there is Phenolphtalein indicator involved. Any thoughts on how I can dissolve the Agar. For info the water bath gets to 110c

Cheers for your help
 
Can you not prepare the agar in the microwave as you would for micro and then stir in the phenolp. etc once its cooled a little.
 
...and I'm sure that you are, but make sure you're using technical agar, not nutrient agar, otherwise you're going to inadvertently grow all sorts of nasty bugs in it!
 
A steam bath is just a beaker full of water heated until it produces steam with whatever it is you want suspended above it in a basin (assuming you can get a large enough set up).

Your water bath goes to where? Superheated water... albeit it is the uneven heating of water baths that the method is attempting to remove with a steam bath.
 

Peter Sigsworth

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Afternoon all. I've been asked to make a ferroxyl indicator gel with the following

Potassium Hexacyanoferrate
Phenolpthalein indicator
Potassium Nitrate
Agar

I've made the solution but the method suggest to sit it on a steam bath so the Agar dissolves. We haven't got a steam bath but a water bath or the microwave. I usually dissolve Agar in the microwave when we do microbiology. Wasn't sure if this was a good idea being there is Phenolphtalein indicator involved. Any thoughts on how I can dissolve the Agar. For info the water bath gets to 110c

Cheers for your help
Heated stirrer to 90 degrees and clears then keep molten in water bath @ 60 so they can handle it and pour into tubes etc.. I do this every year. Edexcel SC13b1 Investigating rusting - if you have labLogger I can share the template instructions/exp request.
 
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I've been known to boil up the agar carefully on a bunsen (watch closely as it can boil over - use a larger than you think flask because it's awful to clean out of the drawers it dribbles into :rolleyes:) then you can add the phenolphthalein etc when it's cooled down enough to handle it. I don't have a heated stirrer. We do have a microwave and an autoclave, but a bunsen works too!
 
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