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Beautiful Liquid Density Experiment Demonstrated with Ocean Layers!

Science for kids is one of our favorite subjects! We’ve done a lot science experiments for kids Today, we will show you an extremely simple way to make a layers of the ocean liquid density experiment. We’ve done other types of liquid density experiments for kids before, but this time, we decided to try and make a density jar that mimics the layers of the ocean! Kids will have a blast with ocean science experiments just like this one!

Easy layers of the ocean liquid density experiment! 3 ingredients and a 10 minute experiment makes this the easiest science fair project ever!

Ocean Density Experiment

Follow these directions to learn how to make your own liquid density experiment that mimics the layers of the ocean.

Ocean Layer Experiment Hypothesis

In addition to learning about the ocean layers, you can explore the density of different liquids in this liquid density experiment. Discuss what liquid the children think might be the most and least dense liquids and objects and record their predictions.

What is Liquid Density in Science?

Different liquids have different densities based on their weight. A cup of oil, for example, will weigh a little less than a cup of syrup.

Liquids with the highest density will sink to the bottom of a cup, while liquids with a lower density will rise to the top.

In general, density is how many particles are inside each liquid. In an equation, density equals mass divided by volume.

When the mass of an object increases but the volume stays the same, the density increases.

In the ocean liquid density experiment, kids can learn how the different densities of water separate the layers of the ocean.

What are the Layers of the Ocean?

Don’t miss the Cartesian diver experiment!

The ocean has several different layers, but there are three main layers, which we represent here.

The surface ocean: This is warm and where a lot of sea life hangs out. The sun lights up this part of the ocean. The surface ocean takes up the top 200 meters of the ocean.

The thermocline ocean: The thermocline is the area of the ocean where the temperature drops rapidly and the density increases quickly. This layer starts at 100 meters and transitions to the deep ocean. The deeper in the thermocline layer you are, the colder it is.

The deep ocean: This is the majority of the ocean (about 90%). It varies in depth, but often still has a lot of ocean life living in it. It is cold and dense. It is typically just above freezing. The deep ocean starts at about  200 meters deep, but can be deeper than 1,000 meters.

How to Turn this Science Activity into a Science Fair Project

Today, we will show you an extremely simple way to make a liquid density experiment. We've done other types of liquid density experiments for kids before, but this time, we decided to try and make a density jar that mimics the layers of the ocean!

To make any science demonstration into a science fair project, all you have to do is have a question and some variables to gest.

You can take this experiment one step further by dropping a variety of household objects of various weights into the liquids. Let your children guess where they think the objects will settle. Use objects like:

  • Coins
  • Plastic beads
  • Bottle caps
  • Plastic bottle caps
  • Popcorn
  • Grapes
  • Safety pin
  • Metal nuts or screws

Denser objects will fall further down the column of liquids (some may fall all the way to the bottom), while less dense objects will stop somewhere along the way. You can use this as an easy way to compare the density of a liquid to a solid.

In addition to learning about the ocean layers, you can explore the density of different liquids in this liquid density experiment.

Record the results and then you have a fun addition to classic science fair projects for kids!

What You Need for a Science Fair

You’ll want to have these supplies on hand before doing your science fair project. Shop the included Amazon storefronts to make things easier and don’t forget to download the free science fair planning checklist before getting started!

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Science Fair Project Planning

When you’re planning your project, you want to keep everything organized. Click the image below to get my free science fair project checklist so you can start organizing your project from the start.

You may also want to check out this list of science fair project research supplies.

Supplies for a Science Fair Project

There are so many supplies for science fair projects that are individual to each project, but if you want a general list of possible supplies and inspiration for your project, check out my selection of science fair experiment supplies on Amazon.

Supplies for a Science Fair Presentation

Your science fair presentation is important! It should look presentable and eye-catching. Check out this list of my favorite science fair presentation supplies.

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More Ocean Science Experiments

If you love the ocean liquid density experiment, you’ll love these other fun ocean science experiments and ocean science fair projects!

Jellyfish in a Bottle Science Project

Easy Ocean Slime Recipe Without Borax!

Ocean-Ready, Easy Egg Carton Oyster Craft for Kids!

Ocean worksheets

Learn about the layers of the ocean and learn about density at the same time!Here is how to set up and complete the ocean liquid density experiment.

Essential Supplies for the Ocean Liquid Density Experiment

  • 3 separate clear containers (we used mason jarsir?t=schomonk 20&l=as2&o=1&a=B001DIZ1NO)
  • 1 large container
  • A heavy liquid (could be honey, corn syrup, or molasses)
  • Water
  • Vegetable oil
  • Food coloring
  • Objects of various weights (metal nuts, marshmallows, pom poms, plastic figures, anything you have lying around your classroom or home that won’t be damaged when wet)

How to Do the Ocean Density Experiment

The ocean liquid density experiment isn’t difficult to do, which makes it a perfect simple science fair project for kids in early elementary school. Follow along with the printable step-by-step directions below for how to complete this fun layers of the ocean science demonstration!

science fair display board example
liquid density experiment

How to Do the Layers of the Ocean Science Project

Prep Time: 10 minutes
Active Time: 45 minutes
Additional Time: 2 minutes
Total Time: 57 minutes
Difficulty: easy
Estimated Cost: $5

I'm completely fascinated by density, and my kids and students have also always been equally excited about learning about how liquids can stay separated based on their density.

I've found that density jars are one of the easiest ways to communicate the concept of density to kids, because it is a bit of an abstract concept, but when they see the same amount of liquid separate, it's clear that there is a reason for that!

Here is how to set up and complete the ocean liquid density experiment.

Materials

  • A heavy liquid (molasses will produce the darkest bottom layer)
  • Water
  • Clear mineral oil or vegetable oil
  • Food coloring
  • Objects of various weights (metal nuts, marshmallows, pom poms, plastic figures, anything you have lying around your classroom or home that won't be damaged when wet)

Tools

  • 3 small containers
  • 1 large mason jar

Instructions

To set up this experiment, first discuss with students the layers of the ocean. The ocean has several layers, but there are three major ones.

  • The surface ocean is warm and home to a variety of sea life. This area of the ocean is illuminated by the sun. The top 200 meters of the ocean are occupied by the surface ocean.
  • The thermocline ocean: A thermocline is an area of the ocean where the temperature rapidly drops and the density rapidly increases. This layer begins at 100 meters and progresses to the deep ocean. The deeper you go into the thermocline layer, the colder it becomes.
  • The deep ocean comprises the vast majority of the ocean (roughly 90%). It varies in depth but often contains a lot of marine life. It's cold and dark. The temperature is usually just above freezing. The deep ocean begins at about 200 meters and can reach depths of over 1,000 meters.
  1. If you are doing this experiment as a science fair project, have your student hypothesize which liquids will be the heaviest and which objects will float or sink. Record the hypothesis. supplies for ocean layer jar
  2. Fill your three containers with 3/4 of a cup each of water, vegetable oil, and molasses.
  3. Dye the water blue and add a bit of blue dye to your molasses.
  4. Layer the liquids in the large container in the following order: Molasses, water, vegetable oil. liquid density experiment science project
  5. Have the student drop different objects into the ocean layers and see where each object settles. This way you can determine how dense each of those objects are,
  6. Record the results and put them in a science presentation. liquid density science fair project
  7. For additional research for older kids, have them find out what types of animals live in each ocean layer and what specific biological functions they use to prevent from being compressed by the dense water in the deeper ocean layers.
  8. Older children may also like to add more ocean layers to their jars.

    Notes

    Turn this layers of the ocean in a jar activity into a science fair project!


    Drop various household objects of varying weights into the liquids. Allow your children to speculate on where they believe the objects will land. Use objects such as:

    • Coins
    • Plastic beads
    • Bottle caps
    • Popcorn
    • Grapes
    • Paper clips
    • Marshmallows
    • Metal nuts or screws


    Denser objects will fall further down the liquid column (some may even reach the bottom), whereas less dense objects will stop somewhere along the way.

    This is a simple way to compare the density of a liquid to that of a solid.


    Record the results in accordance with your science fair's rules and present them on a tri-fold science fair presentation board.

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