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Specialty Chemistry Forums => Citizen Chemist => Topic started by: Skootch on February 07, 2018, 01:20:45 PM

Title: Exothermic reactions with specific thermodynamic properties [REQUEST]
Post by: Skootch on February 07, 2018, 01:20:45 PM

Hi All,

I would like to find an exothermic reaction which can reach upwards of 150-200 degrees Celsius for a short period of time (5-15 minutes). I would like to heat up only 0.05 grams of a certain material.

I so far have been researching a "supercharged" iron oxidation reaction with a salt catalyst in aqueous environment (or with activated charcoal with water in the pores).

I have also been looking into Potassium Ferrate reduction with water, but I am not sure if this will produce heat.

I know that hand-warmer companies have engineered the packets to not get too hot too fast, and to last for hours. I wish to do the OPPOSITE, create a very speedy oxidation reaction which produces a lot of heat very quickly, and then subsides.

Would anyone have any expertise or input on this? I am trying to avoid seriously toxic components, but any suggestions are super helpful.

Thanks in advance everyone.

Title: Re: Exothermic reactions with specific thermodynamic properties [REQUEST]
Post by: tomventiegemail on November 22, 2018, 05:03:35 PM

i got the same question, you didnt receive any answers here?
did you ask elsewhere?
did you find a solution?

Title: Re: Exothermic reactions with specific thermodynamic properties [REQUEST]
Post by: Corribus on November 30, 2018, 10:21:01 AM

Thermite is the obvious answer for really rapidly heating chemical reaction.

https://en.wikipedia.org/wiki/Thermite

But it may be overkill.

The original post indicates some lack of clarity on the part of what is desired, which is probably why the post didn't get much attention. I.e., target temperature, mass of material, and rate are all mentioned. These are all related but different concepts. Heating rate of a substance to a target temperature is a complex function of not only the heating source, but the heat capacity and transfer properties of both the source and the target, it's initial temperature, and any phase changes it must go through.  Likewise how fast a reaction mixture reaches a target temperature depends on a lot of properties, such as the reaction thermochemistry, the quantity, shape and materials of the reaction vessel, and how the reactants are introduced to each other. None of this information is provided in the opening post, so any answer that could be provided would only be general.