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I understand that talcum powder is insoluble to water, would alcohol or something be able to dissolve it?

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Talcum powder is made from talc, a silicate mineral with formula unit: $\ce{Mg3Si4O10(OH)2}$. Silicates tend to be pretty much insoluble in water, but it is possible to dissolve them in strong acids. I don't know about talc specifically, but many silicates can be dissolved in concentrated nitric acid. Hydrofluoric acid is also commonly used for dissolving minerals for chemical analysis. Both are very very dangerous substances that really shouldn't be used without proper training and safety equipment. I don't think there's really anything accessible for a home experimenter, unfortunately.

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  • $\begingroup$ would dissolving talc in strong acids then make the properties of talc change? I understand that acids can be solvents but i would think acids are very strong and are mostly oxidizing agents (especially nitric acid) $\endgroup$ – Nick Sep 10 '14 at 5:03
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    $\begingroup$ Well it won't be talc anymore. Dissolving anything changes its properties to some extent. Talc is only talc because it has the composition it does in the atomic arrangement it does. In order to dissolve, the talc must lose its solid structure. In the case of using an acid, you're right that an oxidation reaction does sometimes cause dissolution, especially with things like elemental metals. When used for digestion, HF tends to pull out Si as $\ce{SiF4}$. In acidic conditions, I found a reference to this dissolution reaction for talc: $\ce{Mg3Si4O10(OH)2 +6H+ + 4H2O -> 3Mg^{2+} + 4H4SiO4}$ $\endgroup$ – Michael DM Dryden Sep 10 '14 at 5:32
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I consider that there is no solvent that can dissolve talcum powder, indeed if you consider "solving" as having your material into solution but maintaining the crystalline structure, only some inorganic compounds (most of them transition metal complexes) are soluble even in water or in other organic solvents (like alcohol).

Quoting wikipedia, we find:

Talc is not soluble in water, but it is slightly soluble in dilute mineral acids.

In any case, solving it will keep intact its structure. This is naturally true for the case of silicates, which are characteristics by their insolubility.

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