For this Easter let us have fun with chemistry and dye eggs. Dyeing eggs is not only great fun for kids but is a central part of the Easter festival. With the increased number of food colouring agents, the way to prepare attractive dyed eggs will not only attract kids to eggs but provide an aesthetic look for these eatable eggs when placed on the dining table.
Here is how to do it
Dip eggs in a single layer in a pan, add water so that the eggs sink in them. Gradually heat the water and bring it to boil. Turn down the heat and allow the eggs to simmer in the hot water. This will make the eggs hard boiled. Cool the eggs and allow the outer shell to dry.
To colour eggs, the following natural colours may be considered:
Brown: Coffee, tea or outer layers of onions.
Yellow: Turmeric or saffron
Purple: beets, purple onion skin
For the next step you may:
1. Mix half to one table spoon of any food colouring material you have; (turmeric, kumkum, saffron etc.), with two teaspoons of vinegar in a cup that is deep enough for the eggs. Fill it with water to about the half way point. Gently place the eggs into the cups (use a soup spoon for this purpose) and avoid cracking. The longer the eggs are left in the dye the darker the shade they turn. You may sequentially add different colours for a differently coloured eggs.
2. If the mark on the boiled egg is made with different coloured crayons and then dipped in the food colouring dye, the waxy portion prevents dye from adhering to the egg and therefore the crayon colours stay with other parts nicely coated with the dye. This will allow the kids to colour their drawings and they can draw any specific figure on the eggs.
3. Wrap a rubber band around the hard boiled eggs and allow the eggs to swim in the dye for sometime. After removing from the dye solution, allow the eggs to dry and then remove the rubber band. The places where rubber band was wrapped will be devoid of the dye whereas the exposed portion is uniformly coated with dye. You may now either paint the rubber band area with another type of dye or dip in a different type of dye!
4. If you wish to have marble designed eggs, place a tablespoon of oil, one tablespoon of vinegar and one table spoon of food colouring. Add enough water to cover the egg, stir quickly and drop the boiled hard egg. Pull the egg as quickly as possible and pat dry with paper towel. Since the oil and water are immiscible, they develop good marbled eggs.
5. You may wish to create a modern art on the eggs: take differently cut sponge pieces, dip them in different dyes and try swabbing the walls of the egg. There could be an overlap of light colour dyes on a dark coloured dye but then you have a design of choice. The other type of colouring includes having molten wax falling on the hard eggs with coloration on it, painting using a cotton swab all are left to the imagination of the kids.
The role of Vinegar
If you were wondering about the role of vinegar in the whole process, vinegar contains acetic acid. Since the shell of the egg is mostly calcium carbonate, addition of a weak organic acid (vinegar) softens the shell surface.
More fun with eggs
You may try an additional experiment by dipping the raw egg in vinegar for a longer time and try checking the spongy nature for the eggs. The egg is so spongy that it enables one to insert the soft egg into a small mouth of a conical flask and when the egg dries again, it becomes harder. This way you can insert an egg with a large diameter into a small mouthed conical flask! Isn't that fun!