Envisioning Chemistry

Chemical Garden II

When a piece of metal salt is dropped in the solution of sodium silicate, a membrane of insoluble metal silicate is formed. Due to the osmotic pressure, water enters the membrane and breaks it, generating more insoluble membranes. This cycle repeats and the salt grows into all kinds of interesting forms. This film recorded the osmotic growth of 6 salts inside sodium silicate solution. The growth was so life-like, no wonder Stéphane Leduc thought it might have something to do with the mechanism life over 100 years ago. (Photography: Wenting Zhu

Teachers can download a Worksheet for using this film in classrooms.

 

Cobalt(II) chloride in sodium silicate solution

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Copper(II) nitrate in sodium silicate solution

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Iron(III) chloride in sodium silicate solution

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Copper(II) sulfate in sodium silicate solution

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Zinc sulfate in sodium silicate solution

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Calcium chloride in sodium silicate solution

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You may wonder, what does "II" mean in the film name? Well, there is a film (below) called Chemical Garden from Beautiful Chemistry three years ago. 

 
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