Floating a Egg in the middle of water By Chris and Ricky
IntroductionWe chose density as our scientific area. Theexperiment we did is related to density columns.We chose density because Chris found theexperiment on Youtube and he found it exciting.
ExperimentOur experiment was trying to float a egg in the middle of water.The steps for doing that were:Step 1: Fill 3 cups with 250ml of water and place a fresh egg inone of the glasses, watch as it sinks.Step 2: Put 4 tsp of salt into one of the glasses stir it up andplace an egg in the water.Step 3: Put 4 tsp of salt into the last cup stir it up and pour outsome of the salt water. Now place an egg in the water. Slowlyand carefully pour fresh water into the glass of salt water.
HypothesisOur hypothesis was that the egg in the second cupwould float at the top and the egg in the third cupwould float in the middle of the water.
Materials Needed:3 Cups900 millilitres of water8 tsp of salt3 Eggs
ResultsThe egg in the second cup floated at the top.The egg in the third cup floated in the middle of thewater.
Why it worksDensity is the amount of space something takes up per volume and whenyou add more mass to the same amount of space being taken up you canchange the density of a liquid. When you drop a raw egg into fresh waterthe egg does not displace enough water making the egg more dense thanthe water around it. That creates an unbalanced force which sends the eggto the bottom of its container. When you add 4 tsp of salt to 250 ml ofwater and stir, the salt crystals break down into molecules and and fill inthe holes in between the water molecules. The solution now has more massin the same space or volume, which changes the density of the water. Whenyou add the egg to the salt water you displace the same amount of waterbut that space has more molecules in it and the egg becomes less densethan the salt water around it. When you slowly add fresh water to saltwater the less dense fresh water floats on top of the more dense salt waterand you create a density column of water. The egg sinks through the lessdense fresh water and floats on the more dense salt water. To makeanything that doesn’t float, such as a bowling ball that doesn’t float, youjust have to increase or lower the density of the liquid you want the objectto float in.
ConclusionOur results supported our hypothesis and we learntabout density and why our experiment works