Track quiz
Here are the seven rules, in the exact words each lab uses.
| Idea | The rule, as the lab applies it |
|---|---|
| Pieces too small to see | Every substance is made of tiny particles. They are too small to see. A piece of chalk is a huge number of chalk particles. |
| Gaps between them | There are gaps between particles. These gaps are called interparticle spaces. Dissolved sugar goes into the gaps between water particles. |
| They never stop moving | Particles never stop moving. They bump into each other and spread out. They spread faster when the water or air is warm. |
| Three arrangements | In a solid, particles are packed close and held by strong pulls. In a liquid, they slide past each other. In a gas, they move freely in every direction. |
| Warming them up | Warm a solid and its particles vibrate more. At the melting point, they leave their places. The solid becomes a liquid. At the boiling point, they move far apart. The liquid becomes a gas. |
| Squeezing | Push a gas and its particles move closer. A gas has a lot of empty space between its particles. A liquid has very little, so water hardly squeezes. |
| What this picture explains | Ask three things. How close are the particles? How strong is the pull between them? How freely do they move? |
Chalk is ground to a fine powder. What is each tiny speck?
Sugar is stirred into water and vanishes. The water tastes sweet. What does this show?
Sugar is added to water. After stirring, the level is a bit lower than with undissolved sugar. Where did the sugar particles go?
What fills the gaps between particles?
A purple crystal is dropped into three glasses of water. One is hot, one is warm and one is ice cold. Which glass turns pink first?
Incense burns in one corner. After a while the whole room smells of it. Why?
How do particles in a solid differ from those in a liquid?
Oil pours from a bottle. A steel spoon keeps its shape. Why?
Table salt poured into a bowl takes the bowl's shape. Is it a liquid?
A solid is warmed until it melts. What do its particles do at the melting point?
A syringe is full of air. The tip is closed. You push the plunger in. What happens to the air particles?
A syringe is full of water. The tip is closed. Why does the plunger hardly move?
Every particle is taken out of a wooden stool. What is left?
Chapter 7 of your NCERT book is Particulate Nature of Matter. Read it. Ask each time: how close, how strong a pull, how free?
Next: Nature of Matter: Elements, Compounds, and Mixtures.