Lesson 7 of 10
What this picture explains
Show on a big screenWhy does soup taste salty when you cannot see any salt? Why do gases mix but stones hardly do? One picture answers both.
Step 1 of 3
- A wooden stool is made of a huge number of particles.
- Take every particle away. Nothing is left.
- The particles are all the stool is made of.
The rule
Salt breaks into particles too small to see. They spread through the soup. Gas particles move freely, so gases mix. Stone particles are held in place, only shaking, so stones hardly mix.
Ask three things. How close are the particles? How strong is the pull between them? How freely do they move?
| The question | The idea |
|---|---|
| Why can you not see salt in soup? | Particles too small to see |
| Why does a smell spread? | Particles always move |
| Why does a gas fill a jar? | Weak pulls, free movement |
| Why does a solid keep its shape? | Strong pulls, fixed places |
Slide the pull. Pick a question. Read the answer.
Loading lab…
Try the lab to finish this lesson.