A Strange Reaction!

[dan1231]

Hi,

 

Here is a weird question:

Is there a chemical reaction that can generate heat for long amounts of time without smoke? In a contained environment.

And, can the same chemicals be used again for the same reaction?

 

The reaction and re-reaction must be simple, could sunlight be used to charge the chemical?

 

Thanks for reading

 

Dan

[Turtle]

Hi,

 

Here is a weird question:

Is there a chemical reaction that can generate heat for long amounts of time without smoke? In a contained environment.

And, can the same chemicals be used again for the same reaction?

 

The reaction and re-reaction must be simple, could sunlight be used to charge the chemical?

 

Thanks for reading

 

Dan

 

I don't know about the sunlight, but would you count an electolytic cell as chemical? Gasses, but no smoke, heat, contained, & reusable to a degree.:naughty: Thanks for writing.:evil:

[dan1231]

Thanks, sounds good...

 

I have a constraint, and that is the size in which the reaction must take place, and what the reaction must do.

 

1.the container must not be more than 30cm length, 20 cm width, 5 cm depth.

2.The reaction must generate enough heat to boil a pot of water.

[Turtle]

Thanks, sounds good...

 

I have a constraint, and that is the size in which the reaction must take place, and what the reaction must do.

 

1.the container must not be more than 30cm length, 20 cm width, 5 cm depth.

2.The reaction must generate enough heat to boil a pot of water.

 

Here is a thread we have discussing heating water by AC electrolysis:

http://hypography.com/forums/chemistry/5332-ac-electrolysis.html?highlight=AC+electrolysis

 

Here's a couple threads on solar reflectors:

http://hypography.com/forums/science-projects-homework/6465-solar-parabolic-trough-charcoal-oven.html

 

http://hypography.com/forums/science-projects-homework/7501-building-parabolic-mirrors.html

[dan1231]

thanks, i'll take a look

[Nootropic]

What about an ammonium dichromate volcano reaction? I don't know how much heat is actually generated, and it definitely appears to not generate smoke. Check it out for yourself:

 

http://http://jchemed.chem.wisc.edu/jcesoft/cca/CCA3/MAIN/VOLCANO/PAGE1.HTM

[Mercedes Benzene]

What about an ammonium dichromate volcano reaction? I don't know how much heat is actually generated, and it definitely appears to not generate smoke. Check it out for yourself:

 

::gasp:: :hihi:

No, no, no!

Can you say "carcinogenic"? This is a very toxic reaction, and I would also imagine quite expensive.

Please do not attempt.

[dan1231]

The ideas and feed back you have all given is good, and I appreciate the help.

I need the reaction to last a very long time (about 4 hours!)

 

 

Imagine I went camping. I had my backpack on, whilst walking, I was some how charging a small container (solar?). come the night, I would boil water and generate heat from this small container. The device could be turned on and off.

The device must be able to be used the next day, as soon as charged.

 

The “device” must be simple, cheap, burn for about 4 hours or more and most importantly it must not kill me (eg. Toxic gas, explosions, catch fire, burn a hole through my hand, you get the picture).

 

Thanks

 

Dan

 

P.S is it possible to get an ultra thin solar panel, can a solar panel be folded up and placed in your pocket?

[Jay-qu]

yes you can get solar panels of the sort!

 

I have seen a reaction, not suited for your purposes, but what it did was a liquid was turned into a solid inside a little heat pack thing and the thing heats up.. hard to explain, but then you boil it and the solid turns back to a liquid ie its reuseable.

[hallenrm]

Let's get the facts straight before we attempt a solution to your problem. You asked

 

Is there a chemical reaction that can generate heat for long amounts of time without smoke?

 

So first of all you must understand what is a chemical reaction? and also how and when does a chemical reaction produce heat?

 

If you really want to know the answer to my first question visit the following link that leads you to an article on chemical reactions in wikipedia.

 

Briefly a chemical reaction, in the common usage of the term, means rearrangement of atoms of a chemical substance, this reaarangement can entail making or breaking of chemical bonds.

When a chemical bond is formed or broken energy, either in the form of heat or light is absorbed or evolved.

 

Thus it must be evident that the heat that can be evolved from a chemical reaction is limited by the number of chemical bonds in the substances involved in the chemical reaction and their bond energy.

 

Explosives are commonly known chemical substances that evolve a lots of heat from small quantities, same is true for many nuclear transformations, radioactive decay etc. which are not conventional chemical reactions. They are used in nuclear reactors to produce lots of sustained heat.

 

I think, you got your reply. :)

[hallenrm]

On further thinking, I think what you need is a rechargable [[battery]] an electrochical cell that can be charged using sunlight. Well devices for both are available, you can have a portable photovoltaic panel that would do the job. However, I doubt it would have enough power to heat sufficient water. :)

[quatumrulesoverall]

Uh, I thought many exorthemics reaction would generate heat without releasing smoke, wouldn't they?

[Mercedes Benzene]

Uh, I thought many exorthemics reaction would generate heat without releasing smoke, wouldn't they?

 

Yes, a lot do. Unfortunately, you don't generally get much energy out of reactions that don't produce smoke. :cocktail:

One simple exothermic reaction is putting calcium chloride in water. A lot of heat is generated just from the CaCl2 dissolving in water! Granted this isn't enough energy to boil water, but it's still fairly interesting.

 

I'll try to work on some sort of reversible reaction that produces sufficient heat.

Quite a challenge.

[quatumrulesoverall]

So do you want to create smoke? I thought you dont :xx: , alright, if yes, why you try combustion of some organic reaction?:hihi: