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Science Rocks!

What's More Dense?


your results

Sent in by:
Paul of Eagan, MN

More dense experimentation!

Materials Needed

  • one cup of water
  • one cup of light corn syrup
  • one cup of cooking oil (like vegetable oil or corn oil)
  • food coloring (to be added to water)
  • nickel
  • grapes
  • Lego(tm) piece
  • one large clear container, like a pitcher



  1. Do you think a grape will sink or float in syrup? How about in water, or in oil?
  2. First, add some food coloring in the water. This will help you see the water. Then, drop one grape into the cup of water, one grape into the cup of corn syrup, and one grape into the cup of cooking oil. In which liquid does the grape float and in which does it sink?
  3. Next, try dropping a Lego(tm) piece and a nickel. Will they float on the syrup, will they float on the water, or will they float on the oil? Or will they just sink?
  4. Then, combine the cups of syrup, water and oil into the large clear container. What happens?
  5. Density is one of the things that makes things float. The three liquids float on top of one another because they have different densities. The syrup is the densest. The oil is the least dense. The water's density is in between the syrup and oil.
  6. All three liquids take up the same amount of space in the container. But the denser one, the syrup, is heavier. That's why the water floats on the syrup. The oil is less heavy than the water. That's why the oil floats on the water.

Keep experimenting with these three liquids and then send any other discoveries you make to the ZOOMsci feedback area.

Some of your Results

Pedro, age 10 of New York, NY wrote:
the grape floated on the syrup

Kelaysia, age 11 of Clarksdale, MS wrote:
The 2 legos floated

Joyce, age 10 of Duluth, MN wrote:
I found that oil is denser than water.

Lorena, age 11 of Toppenish, WA wrote:
I filled a tub with water then I threw in a regular Pepsi then a Diet Pepsi. The Diet Pepsi floated and the regular Pepsi sunk because it had a greater amount of sugar. pretty wicked experiment!

Faith, age 12 of New York wrote:
it worked. the grape floated on the syrup. the nickel didnt float on the syrup because of its presure. the water floated on the syrup and the oil floated on the water

Angel, age 12 of Denver, CO wrote:
the grape had the most density

Patricia, age 10 of Chicago, IL wrote:
the grape did not float only in oil the toothpick floated th eraser sinked

Ana, age 10 of New York, NY wrote:
It worked just like when you did it! It was amazingly awesome! so cool!

Taylor, age 13 of St. Johns, NF wrote:
The same thing happened expect I used a penny and it floated on top of the corn syrup! And after I tried putting milk in it and it turns out that it has less density than corn syrup but more density than the oil and it made like milk bubbles formed with oil, water and milk! it was pretty cool!!!

Aditya, age 8 of Toronto, ON wrote:
The grape stayed longer compare to the popcorn seed, and the whole rasin was the same as the rasin.

Jacob, age 6 of Montreal, QC wrote:
We put water, oil, corn syrup and liquid hand soap together in a glass. The oil floated on the water, the water floated on the liquid hand soap, and the liquid hand soap floated on the corn syrup. The salt floated on the oil, except for some globs of salt that sank to the bottom of the glass. The ice cube floated on the oil until it started melting then it sank to the water level and floated on the water. The Lego and the grape floated on the water (between the oil and water). The nickel sank to the bottom of the glass.

Chelsea, age 14 of Columbus, GA wrote:
The molasis went to the bottom.

Tate, age 11 of Baudette, MN wrote:
The same result that was supposed to. Syrup is most dense.

Kemar, age 6 of Hollywood, FL wrote:
The apple juice stayed at the top and the vegeatale oil stayed at the top juice stayed at the very botom.

Kyle, age 10 of Kennetcook, NS wrote:
The water floated on the corn syrup then the oil floated on the water. I put ketchup in it and it all came apart.

Kayelan, age 12 of Gallatin, TN wrote:
I loved the project. I did it at home since I'm homeschooled. I used light corn syrup, vegetable oil, and water. The funny thing was, I didn't have any blue food coloring! So I used purple! I love purple. And everything worked great, but when I dropped the grape in, I couldn't at all! But I looked on the top and saw the grape. I blend in the purple water.

Kajamil, age 7 of Lancaster, PA wrote:
My object floated in the cooking oil and in the water, and in the corn syrup. It floated because it had air in it. It also weighs less than the cooking oil, water, and the syrup. That's how.

Jack, age 13 of Bronx, NY wrote:
When I did this I instead of a nickel I dropped a quater and in sunk in the bottom and the grape floated on the water and the raisin floated on the syrup. I didnt use any of the other materials.

Laurel, Nathan & Joel of Upland, CA wrote:
We added flour to the solution instead of of salt. We noticed that flour was lighter than the oil so it stayed on top. Chunks of it fell down in round globs and then oil released from the globs and floated up in bubbles. The big chunk of flour stayed on top of the oil. It was cool!

Sophie & Reuben, age 5 of Keene, NH wrote:
We did the experiment with water and olive oil. We used olives, paper, legos, pennnies, and balls. The olive and penny sank in both jars. The paper and legos floated in both jars. The ball floated in water, but sank in oil, but when we combined the water and oil, the ball floated in the oil, which was on top of the water.

Taylor & Dimond of Guilderland, NY wrote:
#1:Coffe-Mate, Veggie Oil, and Water. We pourd the water in first, then the oil, and then the cofee-mate. When the cofee-mate was pourd, it mixed wit the water and the oil went on top.

Isis, age 10 of Margate, FL wrote:
I used honey instead of syrup and in it the penny was the only thing that sunk. The experement woeked great I used it for my project at school.

Kassandra, age 12 of Bridgeton, NJ wrote:
I used colored water Vegistable oil and corn syrup. The corn syrup sunck to the bottom the colored water was between the corn syrup and vegistable oil. Pour them at diffrent times the less dense will float to the top.

Josie, age 12 of Vancouver, BC wrote:
I tried it with water, oil and normal corn syrup. The results were awsome! I really liked the way that when I mixed it all up it leveled it's self out. And when I droped a piece of paper, it sunk threw the oil but floated on top of the water. I'm even going to do this project for school!

Kianna, age 7 of Houston, TX wrote:
I got pretty much the same results as everyone else. When I combined all three liquids, it was neat to see the grape at the bottom of the water, floating on the corn syrup. I wanted to see an object at the bottom of the oil floating in the water - I tried a hair barrette, a pretzel stick and a small rubber ball. RESULTS: Although all the objects were light enough to float on the water, they were not heavy enough to float through the oil. If anyone finds and object that is heavier than oil but lighter than water, please publisize your results!

Anna, age 5 of Madison wrote:
When we tried oil and water, the oil floated to the top. When I dropped ice cubes in, they floated in the oil, ABOVE the water. This surprised us (my dad and me) because ice is made of water. We thought it would float in the water but not in the oil. This means the oil is heavier (denser) than the ice cubes.

Rebekka, age 7 of Allentown, PA wrote:
The chocolate went to the bottom, the water went to the middle and the oil went to the top. I then added some salt which stayed in the layer of oil.

Skyler, age 10 of West Concord, MN wrote:
The lego sunk in all but the Corn Syrup. The nickel sunk in all. The grape sunk in all but the Corn Syrup.

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