100 Days of Science #18-- Floating Eggs

We watched a super fun marine biology class on the computer a couple of weeks ago and at the end of the video we were given a list of fun experiments to try at home.  We could not wait to dive in!

I already had all the ingredients needed to try floating a hard boiled egg in salt water so that's what we started with. It was a lot of fun and I actually encouraged each boy to try this one on their own.

For this experiment you will need:

A hard boiled egg (we used one each)
A clear jar big enough for the egg to move up and down freely
water
salt
a spoon or stick for stirring

We began by filling each glass about half way with water.  You want to make sure the water completely covers the egg.  At this point the egg will be lying nicely along the bottom of the glass.

My kids began slowly adding salt to their glass.  They had some debate about whether sea salt or regular table salt would work better so they experimented with different kinds.

As they poured the salt in they periodically stopped to stir up the salt.  Sometime they stirred around the egg, other times they tried removing the egg/ stirring/ and then putting it back in.

It took a LOT of salt before we began seeing the egg move away from the bottom of the glass.

Evan, who used only table salt, was the first one to get his egg to float all the way to the top of the glass.

I then asked him if he could get his egg to float or suspend between the top of the glass and the bottom so he added just a little bit of water.

As the salt settled to the bottom we could more clearly see his egg "floating" in the middle of the glass

 Alec was next to get his egg to float! He quickly added a bit of water and managed to get his egg to float too.

Ian used the most salt (can you see it all in the bottom of his glass?)  His egg floated right to the top and he really didn't have room to add any more water.

He found just a tiny bit of water made the egg sink a bit and it looked so neat when some of the salt settled back down and the water cleared up just a bit.

This was such a fun experiment learning about density and buoyancy. 

Others in this series:

1. Bernoulli's Principle
2. Ecotarium Trip 
3. Air Molecule Experiment
4. Kitchen Science
5. Corn Maze Field Trip 
6. Birds of Florida 
7. Making Static Music
8. Un-Make It Monday
9. Wind Tunnel Experiment
10. Biomes Field Trip
11. Disappearing Coin Trip
12. Snuffing out a Candle With Baking Soda
13. Making Plastic from Milk
14. Friction Experiment 
15. & 16. Snow Experiments
17. Making an Iceberg

19.  Looking at Microscopic Organisms 

20.  Eco Plant pals

21&22.  Two Experiments with Cotton Candy

23. Springfield Science Museum Trip

24.  Teaching Children the Signs of Spring

25.  Color Changing Slime

26.  Growing Tickle Me Plants

27.  Learning About Soil Sampling

28.  Making Super Bouncy Balls 

29. Exploring the New England Shoreline

30.  Color Changing Flower Experiment 

31.  Roger Williams Zoo Trip

32.  Edible Silly Putty 

33.  Raising Tadpoles

34. More Microscope Fun

35. Making Homemade Ice Cream

36.  Observing Plants Breathe 

37.  Trip to Save the Bay Exploration Center and Aquarium

38. Making Fresh Peach Preserves 

39.  Making Solar S'mores

40.  Growing a Crystal Garden

41 & 42.  Jolly Rancher Candy Apples and Lollipops

43.  Volcanic Lemons 

44.  Oozing Pumpkins 

45.  Growing a Germ Farm

46.  Looking at the Germ Farm Under a Microscope

47 & 48.  Building Model Molecules Two Ways 

49.  Kitchen Chemistry Experiments 

50.  Fall Leaf Chromatography 

51.  Color Changing Experiments with Iodine

52.  Learning About Birds in Winter

53. Iodine and Starch Experiment
54. Flouride and Calcium Experiment
55. Botanical Gardens in Winter
56.  Making Cell Models
57. Which Has More Water; Ice or Snow?
58. Exploding Snow and Water Baggies
59.  Exploring Minerals
60. Visiting the Hartford Science Museum
61-63. 3 STEM Bridge Challenges
64. Making Models of the Earth
65. Plate Techtonics with Graham Crackers
66.  Homemade Lava Lamp
67.  Science Movies We're Watching
68. Index Card Towers
69.  Botany at the Botanical Gardens
70. Best Board Games for Science 
71. Homemade Frozen Yogurt Pops
72.  Starburst Rock Cycle 
73. & 74. Sinking a Marshmallow
75. Jumping Conversation Hearts 
76-78. Building a Paper Airplane 3 Ways 
79. Learning About Hummingbirds 
80.  Planting an Herb Garden 
81. Mushroom Spores 
82. - 84.  Penny Saturation Experiments 
85. Sink or Float?
86. Disappearing Ink 
87. Sedment Layer Jars
88. Tie Dye Science 
89-91. DNA Experiments 
92.  Homemade Butter 
93. Floating Marker Art 
94. & 95. Oil Spills & Water Filtration 
96.- 98. Making Rock Candy & Rock Candy Experiments 
99. Rocket Science 

100. Permaculture Garden Tour