Which solids dissolve in water?

Todays experiment is very simple, but hopefully fascinating for even very young children. We’re going to investigate which solids dissolve in water.

What you need

  • Transparent containers
  • Water ( hot and cold )
  • Substances to try and dissolve eg. sugar, coffee, pepper, sand.

dissolving experiment


Add a teaspoon of whichever solid you are testing to a glass of cold water and a glass of hot water, stir and observe the difference.

Look to see if the solid dissolves in the hot water and cold water and if one is better than the other.

Can you design a chart to record your observations?

Which solids dissolve in water

Things like salt, sugar and coffee dissolve in water. They are soluble. They usually dissolve faster and better in hot water.

Pepper and sand are insoluble, they will not dissolve even in hot water.

flour and water

For older children

Everything is made of particles which are always moving. When a soluble solid ( solute ) is mixed with the right liquid (solvent), it forms a solution. This process is called dissolving.

Two things that affect the speed at which the solid dissolves are temperature and the size of the grains of the solid. Caster sugar which is made of fine particles will dissolve quickly, but bigger sugar particles will take longer.

Solids dissolve faster in hot water as in hot water the water molecules are moving faster, so bump into the solid more often which increases the rate of reaction.


Which solids dissolve in water?

Did you know we now have a book?

Science Sparks Book

There are 25 comments

  1. Smallgood

    For some reason, I struggled to understand solids dissolving in liquids. It was probably until I was in high school and taking Chemistry before I really got it. 😉 I like the little experiment.

  2. Beth

    Very fun & simple enough for my little ones! Welcome to TGIF LInky Party. Thanks for linking up. Don’t forget to grab the TGIF button for your post or sidebar so others can find the party & link up too. Thanks & see you next week,
    Beth =-)

  3. Victoria (Cherry Bomb Bakery)

    Loved this experiment – My daughter is nearly 5 and she loved setting up and carrying out the experiment 🙂 We wrote about it first a nd then after we wrote our findings down and then the sciency part too – She has to practise her sentence writing for school (she is in YR R) and it’s not a secret that my daughter loves to write. I wanted to give her a reason to write so experiments are a great way so I don’t have to pluck a random sentence out of the air on demand – THANK YOU THANK YOU THANK YOU!

  4. Seriously Cool 5 Minute Science Projects for Kids -

    […] One of my favorite experiences as both a teacher and mother is when my kids (real and classroom) have the “AHA” moments.  And with this neat water experiment, your Little Einsteins will be saying “H2-Ohhh!” before you know it!  You’ll need various cooking and baking items such as baking powder, salt, sugar, pepper, various candies, and/or other spices.  Watch what happens when water is mixed with each and then discuss the science behind what makes an object soluble or insoluble in water.  Find the activity DIY here and an excellent lesson behind the science from Science Sparks. […]

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