The Floating Egg
We have 4 glasses of water. If we put sugar in the first glass; salt in the second, flour in the third, and nothing in the fourth, which one will the egg float in first?
We predict the egg will float in the flour water first because the flour looks the thickest.
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The Science Behind It
What is salt? Salt is a natural mineral made up of two
elements, sodium and chlorine.
What is sugar? A sweet crystal substance gotten from many
plants, such as sugar cane and sugar beet, used to make food sweeter.
flour? A powder gotten by crushing
grain, usually wheat, used to make bread and cakes.
What is density? Density
is the amount of space in an object. For
example, a balloon may be the exact same size as a bowling ball; but, if you
have a bathtub full of water and you put the balloon in the water it will not
overflow, if you put the bowling ball into the same tub the water it would
What happens if you add an
ingredient to water? If the ingredient
dissolves in water then the density of the water will change. This mixture is called a solution. Once enough of an ingredient is added,
changing the density of the water, the egg will float.
Why does an egg float in water? It cannot float in plain water because the
density of the egg is greater than the plain water; therefore, the egg will
sink. When enough salt is dissolved in
water, it makes a solution and the water becomes more dense. The increased level of density of the water causes
an upward push, allowing the water to float the egg.
Will sugar dissolve in water? Yes, sugar dissolves in water making a
solution, but it dissolves better in hot water than in cold. For this reason more sugar has be added than
salt to float the egg.
The flour will not dissolve in water like
the salt and sugar did. After adding many
tablespoons of flour, and continuing to stir the mixture, the egg will finally
float. When the flour and water is mixed
together, it never dissolves in the water and eventually settles to the
bottom. This is called a suspension. The egg will temporarily float because it is suspended
in the water.
We reject our hypothesis because the egg floated in the salt water first not the flour. The egg floats in the salt water first because it is the densest. Just like it is easier to float in the ocean because salt water allows us to be buoyant.( buoyant means: able to stay afloat or rise to the top of a liquid or gas) Sugar is the next dense. It takes 6 tablespoons to make the egg float. The next variable, flour, does not change the composition of the water and does not allow the egg to float. In the demonstration flour just builds up at the bottom of the cup and the egg just rests on the flour. Lastly an egg can never float in regular water unless you add a variable as demonstrated
I am 10 years old and I have a younger sister in 3rd grade. I love soccer and cheerleading.
I am 10 years old and I have two younger brothers one in 3rd grade and one in 2nd grade. I love playing basketball and lacrosse.
We are Melissa and Nadia
We worked great together on this exciting science project because we are such good friends.