A "rubber egg" is made by soaking a raw egg with its shell still intact in regular household vinegar for a specified length of time. In 2 to 3 days the egg shell will be completely dissolved by the vinegar, leaving behind the egg cell membrane, which will have taken on a rubbery consistency that holds the egg together.Know More
The shell of an egg is made of calcium carbonate, which is the same composition as that of limestone. The acetic acid in vinegar reacts with the calcium carbonate shell to produce carbon dioxide gas and dissolved salt. This reaction gradually wears away the hard shell of the egg until it is completely gone. The "rubber egg" science experiment is a favorite among elementary students all over the world and it is often conducted to demonstrate the importance of calcium for the bones and teeth.
To make a rubber egg, one will need the following:
Place the egg inside the container gently. Make sure that the egg shell and the membrane are intact.
Pour the vinegar into the container until the egg is completely submerged. Bubbles may already start forming on the shell of egg a few minutes after pouring in the vinegar. Set aside for 2 to 3 days.
After 2 to 3 days, the egg shell will have completely dissolved, leaving a muck floating on the surface of the vinegar. Pour out the vinegar and gently take out the rubber egg.
The rubber egg experiment also demonstrates the semi-permeable properties of the egg membrane, which allows the vinegar to pass through the membrane freely. This same experiment can also be done with chicken bones with the same result, although it may take a few more days to fully dissolve the calcium in the bones.Learn more about Chem Lab
Those who can't tell whether an egg is hard boiled or raw can tell the difference by placing the egg on a flat surface and spinning it by hand; a cooked egg will spin smoothly, while a raw egg will wobble. The difference in spin quality between a raw and hard-boiled egg is due to the yolk. In a cooked egg, the yolk will be solidly encased within the cooked white and will not be able to move when spun, leading to a smooth spin, while a raw egg's yolk will be able to move freely, which will cause the egg's center of gravity to shift as the yolk moves within the egg.Full Answer >
Whether or not an object, such as an egg, floats is a function of its density relative to the medium it's submerged in. Objects that are less dense than their surroundings are buoyant and float. Objects that are denser than their surroundings sink.Full Answer >
If you prepare the hard-boiled egg beforehand, you can complete this demonstration in just a few minutes. This experiment requires the egg, an appropriately sized glass bottle, a sheet of paper and a match. A typical juice drink bottle has the right size opening.Full Answer >
An element is made of only one kind of atom, while a compound contains the atoms of two or more elements. For example, gold is made of only one kind of atom, so it is an element, but water is a mix of hydrogen and oxygen, so it is a compound.Full Answer >