Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: MarianaM on 22/08/2019 13:49:53

Title: Ethanol replacement for a red cabbage-based natural indicator?
Post by: MarianaM on 22/08/2019 13:49:53

Ashley asks...

I have to make a natural indicator at home for a project and test household items, I chose to use red cabbage but I don’t have ethanol as the instructions suggest, can I use acetone or nail polish remover instead?

Can you help?

Title: Re: Ethanol replacement for a red cabbage-based natural indicator?
Post by: alancalverd on 22/08/2019 14:26:26

Try vodka. The traditional unflavored clear spirit contains very little apart from water and ethanol, and is the optimum concentration for cleaning inkjet printer heads! Also delicious mixed with sloe juice and sugar, or raspberry juice. These ay even have indicator properties.

Red cabbage juice is generally adequately soluble in water anyway, and cooked strips of red cabbage make a handy substitute for litmus paper.

Beetroot is interesting as it changes color at a much higher pH than cabbage.

Worth playing with turmeric too, though you may need an oily solvent like carbon tetrachloride ("Thawpit" or "Dabitoff" greasy stain remover) or turpentine paint thinner to get a strong enough solution.   

Title: Re: Ethanol replacement for a red cabbage-based natural indicator?
Post by: Bored chemist on 22/08/2019 18:54:28

You can probably get away with using methylated spirit.
The purple colour will be "painted over" by the cabbage.