Extracting iodine from seaweed

A close-up photograph of wet laminaria ribbon seaweed (or kelp) on a beach

Source: © Shutterstock

Discover how ribbon seaweed (or kelp) can be used as a source of iodine in this demonstration or class experiment. Includes kit list and safety instructions.

Ribbon seaweeds contain iodine compounds which they obtain by extracting iodide ions from seawater.

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