Loading ...It’s a classic experiment and a sure-hit favorite around Easter. 
Soak a raw egg in vinegar and over the course of time, the vinegar will dissolve the eggshell. What you’re left with is the egg’s translucent membrane to protect the egg. Even though it’s a classic, I’ve never done this demo on the television show because it takes so long for the eggshell to dissolve in vinegar (about 7 days). But this year I had to try something new. What about substituting 3 molar hydrochloric acid for vinegar? The goal is to dissolve the calcium carbonate in the egg shell and 3M HCl should do the trick. The first attempt was a success, but I stumbled upon a great technique at the same time. Instead of doing the reaction in a beaker, I put the egg in a 1000 mL graduated flask and cover the egg with 150 mL of 3M HCl. This makes the reaction easy to see and very controllable. As the acid dissolves the egg, carbon dioxide gas is produced and a white foam of calcium chloride slowly rises in the cylinder. When the reaction is complete (you’ll see the naked egg), rinse the egg and… Voila… you got a naked egg! Watch the video.
Before you flood the post with comments, I know that hydrochloric acid is not in the kitchen chemist’s bag of goodies. But you have to share something for the chemistry teachers every once in a while.
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April 21st, 2006 at 5:35 am
Very cool. Where can I get some 3M HCl so I don’t have to wait 7 days?
May 17th, 2006 at 9:13 pm
Befriend a high school chemistry teacher. 3M HCl is still a relatively strong acid and needs to be respected. Have a chemistry teacher help you remove the shell after school - it should take about 3 minutes at the most.
May 27th, 2006 at 10:30 pm
i am doing a science progect and i was w discoverd this chemical reaction like an awsome scientist like you or another scientist
May 27th, 2006 at 11:40 pm
I don’t understand how you get the membrane to fluff up again with air. You poke two holes in it? How do you fold it?
May 27th, 2006 at 11:57 pm
By just bouncing the egg membrane between your hands, a little air works it’s way in through the holes. After a few seconds, the membrane fills with air and the egg looks restored. Be sure to take a look at the video…
http://wm.kusa.gannett.edgestreams.net/news/1144710032384-04-10-06-spangler-4p.wmv
October 12th, 2006 at 11:47 am
sweet! im doing this experiment now, but with a twist! isnt that awsome?
February 16th, 2007 at 1:34 am
We have been trying to dissolve an eggshell with Diet Coke, but so far the soda has just become very murky. Are the acids in sodas able to dissolve an eggshell? Should we be changing the soda around the egg daily? Could that make a difference?
March 15th, 2007 at 9:19 pm
Has anyone had success dissolving an eggshell with soda?
April 23rd, 2007 at 2:00 pm
I like the experiment but i wished it was only three days because i have to do a science experiment
December 2nd, 2007 at 9:40 am
looks really cool. Where can I see the cooked egg demo?
February 6th, 2008 at 8:33 pm
I have done this egg experiment many times with my grandchildren, each time a young one is amazed, I ran out of grand kids, but I actually have a naked egg in a glass of water now waiting for the kids to ?? should I bring it to their school? well finally they said yes, but I didn’t have to wait 7 days, my distilled white vinegar only took 2 or 3 days, it helps to rub the shell off if in a hurry, that works faster, as the children only were at my home for 3 days in a row, so I wanted to “rush it” they loved it, and the older one had forgotten about it when we did it as a youngster, also I have stood an egg on end during the “Spring Equinox” that really shocked them, but my timing has to be correct with that as well, gravity is a playful thing sometime!
February 6th, 2008 at 10:41 pm
Some people use concentrated vinegar - available in many grocery stores - to speed up the process, as well. Chemistry teachers have the luxury of using hydrochloric acid (3 molar works well) and the process goes very quickly (just a few minutes), but handling and disposing of the remaining acid has to be left to the chemistry teachers who know what they’re doing.
Sharon… your grandchildren have to think you’re the coolest science grandma!