Introduction: How to Dramatically Demonstrate a Decomposition Reaction

This chemical volcano is a result of the decomposition of Ammonium Dichromate.

A decomposition reaction (aka analysis reaction) follows the general formula below

A--> B + C

A compound breaks down into smaller components.

This is the demonstration of the decomposition of Ammonium Dichromate

(NH4)2Cr2O7 ---> N2 + 4H2O + Cr2O3

Cr2O3 -the green solid


Chromium III and chromium VI, as well at its compounds, including ammonium dichromate, are known carcinogens. Chromium will irritate the mucous membranes. Therefore, take care to perform this demonstration in a well-ventilated area (preferably a ventilation hood) and avoid skin contact or inhalation of the materials. Wear gloves and safety goggles when handling ammonium dichromate.


antienoob (author)2009-07-29

were could i find the materials needed for this. cose i so wont to try this at home.

pwest71 (author)2009-06-25

Any way to make a similar effect, but safe for in a home? Looking to make a "faux" volcano/waterfall.....

MacLean (author)2009-05-17

so what chemical is first burned? ammonium?

duckman1970 (author)2009-05-17

yah it worked whoooo BANG! ahhh ahhhhh ahhhhhhh sick volcano man

szechuan53 (author)2009-04-21

very nice I also needed a shovel (I just used a little beach shovel though)

hacedor (author)2009-03-26

I needed a shovel!?!

The Fallen (author)2008-09-21

this is a decomposition reaction, where is all the energy coming from? breaking bonds requires energy, correct?

Holden_vy_s (author)The Fallen2009-02-10

Heat is energy. Did you now watch the clip?

Well, he kinda heated it up with a torch.. =/ If that's not energy, then I don't know what is.

Arbitror (author)2008-12-18

That is neat!

I_am_Canadian (author)2008-07-28

lol looks like a volcano

alwinovich (author)I_am_Canadian2008-08-21

nice jou must be the first one to notice that on the whole world! congrats! would you like a cookie?

alwinovich (author)alwinovich2008-08-24


I_am_Canadian (author)alwinovich2008-08-21

I would love one, thanks.

tubajoey1 (author)2008-08-13

where might i get the materials for this? like, somewhere i could go locally, not the internet. thanks!

big-jamie (author)2008-07-12

makes a hell of a mess lol but very cool (H)

GorillazMiko (author)2008-02-02

Looks awesomely awesome to the most awesomeness of awesome, keep up the great videos!

tyeo098 (author)2008-02-02

Ultimate science fair volcano!

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