Impressive experiments with iodine to show your kids

Easy experiments with iodine

[Deposit Photos]

The im­por­tance of io­dine in hu­man life

Io­dine is an el­e­ment that holds 53rd place in the pe­ri­od­ic ta­ble. It is a non-ra­dioac­tive non-met­al. It is very im­por­tant in hu­man life. A lack of io­dine in the body caus­es re­tar­da­tion in phys­i­cal and men­tal de­vel­op­ment, and growth de­fi­cien­cies. A deficit of io­dine also caus­es hy­per­thy­roidism. Al­though the io­dine con­tent in the or­gan­ism is low, 25 mg, this does not make it any less im­por­tant for the body. It also takes part in the me­tab­o­lism process. The io­dine in the body is main­ly con­tained in the thy­roid gland. So it is im­por­tant to in­clude ad­di­tion­al io­dine in our diet, es­pe­cial­ly in re­gions where there is a low io­dine con­tent in the wa­ter.

Io­dine is also found in na­ture, for ex­am­ple in al­gae. It is also pro­duced chem­i­cal­ly through cer­tain re­ac­tions.

[Deposit Photos]

A lit­tle his­to­ry about the dis­cov­ery of io­dine

In dis­cov­er­ies, ev­ery­thing is al­ways sim­ple and ac­ci­den­tal. The dis­cov­ery of io­dine can be blamed on a cat which knocked over so­lu­tions in flasks. One flask con­tained the re­mains of iod­ic salts treat­ed with salt­peter, and the oth­er con­tained sul­fu­ric acid. The cat’s own­er, the French chemist Bernard Cour­tois, no­ticed a vi­o­lent re­ac­tion when these two com­po­nents mixed, with the re­lease of pur­ple va­por. This was io­dine. An el­e­ment with­out which we could not imag­ine life.

Ex­per­i­ments with io­dine

Io­dine is a very good in­di­ca­tor, so any re­ac­tion with this el­e­ment is very easy to ob­serve. You can con­duct a few ex­per­i­ments with your kids, as these ex­per­i­ments are very sim­ple and ed­u­ca­tion­al. At school they don’t al­ways find the time for such ex­per­i­ments. So you can eas­i­ly car­ry them out at home and show the kids what an in­ter­est­ing sci­ence chem­istry is. Click here to find out how to re­veal fin­ger­prints with the help of io­dine Ex­per­i­ment “Find the starch”

With this ex­per­i­ment we can see what prod­ucts con­tain io­dine, and how much of it. You will need:

  1. 5% io­dine so­lu­tion;
  2. starch;
  3. pipette;
  4. dis­pos­able cup;
  5. prod­ucts with and with­out starch.
[Flickr, Creative commons by Tess Watson is licensed under CC BY 2.0]

First make an io­dine so­lu­tion. Even a child can do this. Take a cup, pour wa­ter into it and add a few drops of io­dine. The so­lu­tion is ready.

Now take dif­fer­ent types of food and place them on a plate: bread, rolled oats, a raw pota­to, a boiled pota­to, a lemon, a radish, a car­rot and a cu­cum­ber. Put sev­er­al drops of io­dine so­lu­tion on them and see how they re­act with io­dine. On the bread, oat meal, cheese and boiled pota­to, a re­ac­tion takes place, and the io­dine turns blue. We draw the con­clu­sion that these prod­ucts con­tain starch. We also con­clude that there is much starch in boiled pota­toes, as the col­or is rich­er. But in radish­es, lemons and cu­cum­bers, we do not ob­serve any starch. So by ex­per­i­ment, we clear­ly see the pres­ence of io­dine in dif­fer­ent types of food.

Ex­per­i­ment “In­ter­ac­tion of starch with io­dine”


To con­duct this ex­per­i­ment, you will need:

  • starch;
  • 3 glass­es;
  • wa­ter;
  • io­dine.

Boil a paste from starch. Take 3 glass­es and pour the paste into the 1st glass, starch with wa­ter into the 2nd, and just wa­ter into the third. Add sev­er­al drops of io­dine to each glass. See the re­sult. In the first cup we ob­serve a so­lu­tion with a rich blue col­or, in the sec­ond a so­lu­tion with a light blue col­or, and in the third a light brown col­or. We may con­clude that the re­ac­tion took place more ac­tive­ly with the paste. Heat-treat­ed starch gave a re­ac­tion more quick­ly.

Ex­per­i­ment “Dis­col­or­ing io­dine”

You can see the re­ac­tion of io­dine and ascor­bic acid For the ex­per­i­ment, take:

  • io­dine so­lu­tion;
  • 2 glass­es;
  • so­lu­tion of ascor­bic acid;
  • wa­ter.

For the so­lu­tion of ascor­bic acid, you will need 20 pills and 60 ml of wa­ter. Pour io­dine into the wa­ter con­tain­ing starch. We get a rich blue col­or. Then mix the so­lu­tion of ascor­bic acid with the io­dine so­lu­tion. The so­lu­tion in­stant­ly be­comes col­or­less. We see some “mag­ic”. The sci­ence of chem­istry does mir­a­cles.

You can car­ry out these ex­per­i­ments to­geth­er with your kids in your spare time. They will find them very in­ter­est­ing and mem­o­rable. Spend time with your chil­dren in a fun and ed­u­ca­tion­al way.