DISSOLVING EXPERIMENT: DOES IT DISSOLVE?

Alumna: María Jesús Sainz Sánchez

Objective

I want my five years old students to learn the concept of dissolving and to recognize which substances dissolve into water and why.

Materials

See through plastic cups, spoons, paper, coffee, salt, rice, olive oil and pepper.

Experiment

1. Material presentation

 First of all, I put 7 different substances on a table and ask the students what they think we are going to do with that.

2. Previous knowledge and free activity

I ask the students whether they know what dissolving is and find out their previous knowledge about the subject. Then, I let the children observe, touch, smell and guess what these substances are (sugar, salt, coffee, rice, curry, oil and pepper).

3. Directed activity

 I ask the students what they think would happen if we put those substances into water. The children have to make hypothesis and predict whether those substances would dissolve or not. After that, they have to dump the substance into a cup with water and stir.

4. Conclusions: confirmation of the hypothesis

We check whether their predictions were right. If the substance dissolves into the water, we put the cup next to a paper that says “yes”, if not, we put it next to a paper that says “no”. Finally, I ask the students, “Why do you think we can see some substances in the water and others we can’t?”

 The children answer what they think. Then, we all together come to the conclusion that it’s because some substances have completely dissolved into water. They are still there, but they have broken into tiny pieces that we can’t see. Some substances dissolve and others don’t.

5. Evaluation

I show them a cup with milk and a bowl with chocolate powder, then I ask them what they think would happen if we mix them together. If they say it would dissolve, it means they have learned the concept of dissolving.

6. Cleaning up together

At the end, once we have finished our experiment, everybody cleans up the mess together.     

* What they have learned: dissolving means to break into really small pieces and to completely mix into a solution.