Discovery Express
  • Welcome!
  • Blog
  • Check out our store!
  • 9 Apples Math Game
  • Your questions answered!
  • About

Floating Egg

6/14/2015

1 Comment

 
Author: Maddie Van Beek

Have you ever heard that muscle weighs more than fat? The truth is, a pound of muscle weighs the same as a pound of fat! It’s just that muscle is denser than fat. Check out the photo below:

Picture
http://cdn2-b.examiner.com/sites/default/files/styles/image_content_width/hash/4d/e6/4de678acd329b0766b9f2b067d49fec6.jpg?itok=x7A5pn0j
As you can see, one pound of muscle simply takes up less space than one pound of fat. This is because the material in muscle is more dense than the material in fat. 



How much do you know about density? If you’ve been following us for a while, you may have tried our liquid stacking tower experiment that demonstrates the densities of different liquids. Check that out here (http://discoveryexpress.weebly.com/homeblog/rainbow-in-a-jar-learning-about-liquid-density)! Today, we are going to create an easy demonstration involving liquid density just by using an egg and salt water. 



What IS density?

Picture
http://astro.unl.edu/classaction/outlines/intro/density.jpg
Even though two different items might take up the same amount of space, their densities may be different. Take a look at the photo below. All of the cubes are the same size, yet some of them weigh more than others. Why is that? Because their densities vary. For example, wood is less dense than steel. 

Picture
http://www.flinnsci.com/store/catalogPhotos/AP6058cat.jpg
Picture
http://inspirationlaboratories.com/wp-content/uploads/2012/11/density-comparison.jpg
As you can see, the object on the left side has greater density than the object on the right side. Although both cubes are the same size, the matter in the left cube is packed more tightly, and thus is more dense than the cube on the right. 



Here is yet another example of the varying densities of different materials. 

Picture
http://www.mathswrap.co.uk/wp-content/uploads/2013/03/Density-cubes.jpg
Make sense? 



Now that you understand the basics of density, here is a video that explains how to find density:

Let’s try our density demonstration! 



YOU WILL NEED:

  • Water
  • Salt
  • An egg
  • A glass
  • Teaspoon



Here’s what to do!

  1. First, fill a glass with one cup of plain water. 
  2. Carefully drop the egg into the glass of tap water. What happens? Make a sketch of the egg in your observation journal and record any other observations. 
  3. You should have seen the egg sink to the bottom of the glass of tap water. What do you think will happen if you drop an egg in a glass of salt water? Let’s find out!
  4. Remove the egg from the glass, and then use a teaspoon to stir salt into your glass of water. Make sure the salt dissolves completely before you add more. Count how many teaspoons of salt it takes before no more salt will dissolve. When you reach the point where salt will no longer dissolve, your water is saturated. You cannot dissolve an unlimited amount of salt (or any solute).  Liquids (a solvent) reach a certain point where they will no longer dissolve any more solute (in this case, salt). 
  5. Now that you have your salt water solution, carefully pour half a cup of tap water on top of the salt water. Make sure you do this so that you disturb the salt water as little as possible. What do you think is more dense, the salt water or the tap water? Why? 
  6. Carefully drop the egg into the glass of water. What do you see? How was this different than the first time you dropped the egg into the tap water? 
  7. You should have seen the egg sink past the tap water in the top half of the glass until it hit the salt water. It “magically” floats in the middle of the glass. Why does it do this? As you know, the salt water is more dense than the tap water, so the egg sinks right past the tap water but floats on the surface of the salt water. 
  8. Extension: How else can you determine which liquids are more dense? Use a balance to compare different liquids. Make sure you use two identical cups with equal amounts of liquids when you are making comparisons. 
  9. Look at the example below: You can see that water weighs more than an equal amount of rubbing alcohol. This means that the rubbing alcohol is less dense than water. 
Picture
http://www.middleschoolchemistry.com/img/content/lessons/3.5/alcohol_vs_water.jpg
10. Find other household liquids that you can compare! Make sure to record your observations in your observation journal.



Since you have eggs already, check out these other “eggcellent” activities! 

Acid Base Reactions: http://discoveryexpress.weebly.com/homeblog/experimenting-with-eggs-acid-base-reactions-and-osmosis

Nature Abhors a Vacuum: http://discoveryexpress.weebly.com/homeblog/nature-abhors-a-vacuum-how-to-put-an-egg-in-a-bottle

Sedimentation and Crystallization: http://discoveryexpress.weebly.com/homeblog/sedimentation-and-crystallization-how-to-make-egg-geodes




References:

  • https://www.youtube.com/watch?v=kE8I_M2pyg8
  • http://www.middleschoolchemistry.com/lessonplans/chapter3/lesson5
  • http://www.sciencekids.co.nz/experiments/floatingeggs.html
1 Comment
Michael link
3/3/2022 01:00:13 am

Great Article! Thank you for sharing this is very informative post, and looking forward to the latest one.

Reply

Your comment will be posted after it is approved.


Leave a Reply.

    Follow us on Pinterest!
    Picture
    Check out our new game for math education, grades 1-7!

    Archives

    February 2019
    January 2019
    December 2018
    November 2018
    October 2018
    September 2018
    August 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    December 2017
    November 2017
    October 2017
    September 2017
    August 2017
    July 2017
    June 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016
    July 2016
    June 2016
    May 2016
    April 2016
    March 2016
    February 2016
    January 2016
    December 2015
    November 2015
    October 2015
    September 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    March 2015
    February 2015
    January 2015
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014
    January 2014

    Categories

    All
    Age 10 12
    Age 12 14
    Age 14 16
    Age 16+
    Age 8 10
    Anatomy/Physiology
    Biology
    Chemistry
    Engineering
    Food Science
    Geology/Earth Science
    Health Science
    Math
    Microbiology
    Physics
    Plant Science
    Psychology
    Weather Science

Proudly powered by Weebly