OREGON STATE UNIVERSITY

Ammonium Dichromate


photo, ammonium dichromate  volcano

A miniature volcano occurs when (NH4)2Cr2O7 is decomposed!  

This mini volcano is analagous to a cinder/spatter cone.

 

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small photo, lighting volcano with bunsen  burner

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small photo, lighting volcano with bunsen  burner

Quicktime

Ammonium dichromate, (NH4)2Cr2O7, is an orange crystalline solid at room temperature. It can be ignited with high heat, such as that from a bunsen burner.

 

small photo, volcano burning

Video for Windows

small photo, volcano burning

Quicktime

The orange (NH4)2Cr2O7 is decomposed according to the equation below:

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

The dark green solid "volcano" is Cr2O3.
Note:   This is quite toxic...
Mirrored from the U. Illinois Dpt. of Chemistry