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Science Rocks!

Make An Egg Float


your results

Sent in by:
Katie of Preston, WA and Jim of AZ

Some science that's sure to float your boat.

Materials Needed

  • water
  • 2 eggs
  • liquid soap
  • cooking oil
  • salt
  • sugar
  • glass
  • tablespoon
  • balance scale



  1. Check with an adult before you begin.
  2. Fill a glass half full with water. Place an egg into the water. The egg will sink because it is more dense than the water.
  3. Start adding salt to the water one tablespoon at a time. Help the salt dissolve by stirring it into the water. What happens? How much salt do you have to add to get your egg to float?

Ready for us to float the science scoop? Adding salt to the water squishes more molecules into the water. This makes the water more dense. When there was no salt in the water, the egg was more dense than the water and it sank. Adding salt to the water makes the water more dense than the egg which makes the egg float. If you weigh a cup of saltwater and a cup of fresh water, the saltwater will weigh more than the fresh water even though it is taking up the same amount of space (a cup). This is because the saltwater is more dense than the fresh water.

Design your own experiment by thinking of a question you'd like answered. Would sugar dissolved in water make an egg float? How about soap or oil? Make a prediction, test it out and send your results to ZOOM.

Some of your Results

Whitney, age 11 of Christchurch wrote:
the sat water floated but the rest didnt I dont know im doing a science fair on it for school

Alex, age 16 of MI wrote:
it floated in the salt water and not in the tap water

Kyana, age 11 of New York wrote:
the egg floated to the top and then I tried to put fresh water in another glass than it didn't float to the top (this was without the salt

Logan, age 10 of Lagrande, OR wrote:
once I put all the objects I used into the licwid I droped the egss they sunk a bet then floated back up to the top and keep floating

Kyla, age 11 of Ozark wrote:
I just put 4 teaspoons in the jar and it floated.

Anood, age 11 of Amman wrote:
The egg floats after I added the salt to the water since the water becomes more dense

Corey, age 12 of Hartford wrote:
I used a hot glass of water and and salt & vinegar I Also had an extra glass I put cold water but it did not work so I used baking soda and I stured it and it floated WOW!

Katira, age 9 of Baltimore, MD wrote:
when I put the egg in the water it didn't float but when I put medium and large salt and started to mix everything the egg floated

Cassie, age 13 of Richmond, NY wrote:
i took about 17 table spoons but then I stired for about 8seconds and then the egg floated but it did work!

Isabel, age 14 of Waco, TX wrote:
it floated for about 8 minites

Kiera, age 11 of Baltimore, MD wrote:
my egg floated when I put in about 3 tablespoons. It was so kool

Reece, age 12 of North Delta, BC wrote:
The egg floated in salt and in cooking oil but not in sugar or vinager

Mikiyas, age 11 of Indianapolis, IN wrote:
it took us 15 tea spoons for the egg to float but it was awesome.

Jalea, age 11 of Buckeye, AZ wrote:
i just added salt to the cup and it floated in the matter of 2 minutes!!!

Faisal of Folsom Sacramento, CA wrote:
it took 7 tris to make the egg float in three cups of water

Mary, age 9 of Sammamish, WA wrote:
the egg floated when I used salt!

Josh, age 12 of Woodmere, NY wrote:
i used sugarwater and saltwater I found out that the more I put in the denser it became but just because its denser doesnt mean I should work better. but since the thickness of it makes it rise the more you put in the more it floats

Daniela, age 11 wrote:
the egg floated in the salt.

Emily, age 12 of Everly, IA wrote:
I put 15tbls. of salt an the egg floated.

Micah, age 11 of Independence, MO wrote:
What happened was I used milk mixed in water to see if the egg would float but it didn't. The egg floated in the salt water "the magic solution".

Mike and Chris of Bethel, AK wrote:
it was fun I mean took a while but was OK. I dont know how to make the egg stay in the middle though hard it either floated or sunk

Kiyona, age 13 of NY wrote:
first you fill the glass up with water then you put salt, vineger, water

Curran, age 11 of Houston, TX wrote:
I used sugar, salt, and oil. the salt did the best, then sugar then oil. THIS PROJECT WAS GREAT!

Keyera, age 9 of Bossier City, LA wrote:
I did it with baking soda and it started to float in hot water then I had an extra glass and it floated to after I dtirred it the I did it with salt in cold water but is stay sunkun so I did one with baking soda and I stirred it and it floated WOW!

Anysia, age 10 of Leesburg, FL wrote:
I put baking soda 2 tesapoons

Jorge, age 15 of Phoenix, AZ wrote:
first I got a cup then I add water 2 the cup and NEXT I addthe egg and 12 scoops and the egg was floating it was cool!!!

Daisy, age 9 of Fontana wrote:
when I put the oil in it, then the egg the egg did not go up but when I put the sugar in it, it went up!

Ren, age 9 of Franklin, TN wrote:
when we put the egg in the salt water it started to float

Johnny, age 16 of CA wrote:
firs I poot a too tabl spoonz an it diddnt flot but thenn I put three mor an it starded to flot. it waz messy but my mom cleand it for me

Antonette, age 14 of Chicago, IL wrote:
when I did this I used vinegar to see if the egg would float and it did and then the vinegar started to cook the shell of the egg which is very cool to watch this procedure you should really try it but so the egg shell disappear it would take approximatley 2 to 3 days

not yet implemented