Solid, Liquid, Gas — Explained

Grade 6 · Particles · Page 1 of 3

Name Date

DIRECTIONS: Use particles to explain why each state behaves as it does.

Solid

Liquid

Gas

Same particles in all three boxes. Count them if you like.

#		Solid	Liquid	Gas
1.	Keeps its own shape?
2.	Can be poured?
3.	Can be squashed into a smaller space?
4.	How are the particles arranged?
5.	How do the particles move?

So What Got Bigger?

Grade 6 · Particles · Page 2 of 3

DIRECTIONS: Heat a metal bar and it gets longer. What got bigger?

A stuck metal jar lid loosens under hot water. Power lines sag lower in summer. Bridges have gaps at each end to close up in the heat.

When the bar got longer, did the particles themselves get bigger? Say what actually changed.

#	Statement	True or false?	Why
7.	When ice melts, the ice particles turn into water particles.
8.	A gas can be squashed because there is empty space between its particles.
9.	When water boils, the particles break apart into smaller pieces.
10.	Cooling a gas down makes its particles move more slowly.

A friend says a gas weighs nothing, because it is mostly empty space. Answer him — and name something from grade 5 that settles it.

Grade 6 · Particles · Page 3 of 3

DIRECTIONS: When heated particles move enough to break away, the state changes. Predict each before reading the next.

#	What is weighed, then left for an hour	Does the mass go up, down, or stay the same?
12.	an ice cube inside a sealed freezer bag, left on the counter
13.	a pan of water boiling on the stove, uncovered
14.	the same pan of water boiling with a tight lid on it

Two of those three have the same answer. Explain why, using the particles rather than the words "melted" and "boiled".
The odd one out lost mass. Was any matter destroyed? Say where it went and how you could catch it.
A kettle's white cloud is tiny droplets that have cooled back down; the gas itself is invisible. Which is closer to the spout — the cloud, or the clear gap in front of it? Why?