States + Properties of Matter
Energy + Phase Change
Mixtures + Pure Substances
Atoms + Matter
100

Name all 3 main states of matter.

solid, liquid, gas

100

When you heat an ice cube, what state does it change into?

liquid

100

True or False: In a mixture, the substances keep their own individual properties.

True

100

What are the tiny particles called that make up all matter?

Atoms

200

Give one physical property (besides state) that can be used to describe or sort matter.

color, hardness, texture, buoyancy, melting/boiling points, density...

200

What happens to molecules in matter when energy is added?

They heat up, moving and spreading them around.

200

Give an example of a solution and explain what makes it a solution.

sweetened tea, Kool-Aid, lemonade, saltwater, the air in this room...

solution: a mixture of substances that is uniform throughout

200

True or False: Atoms make up the mass of solids and liquids, but not gas.

False! Atoms make up all matter!

300

Explain why a liquid takes the shape of its container but keeps the same volume, while a solid does not change shape at all.

In a liquid, molecules can move past each other and flow into a container's shape. Molecules in a solid cannot slide past one another and have a fixed shape.

300

Put these in order from least energy to most energy: liquid water, ice, water vapor.

ice < liquid water < water vapor

300

A bowl of trail mix with raisins, nuts, and pretzels is a mixture. Is this a solution or just a mixture? Explain.

Not a solution: all of the separate parts are visible and not evenly distributed throughout the mixture.

300

You are shrunk down small enough to see the atoms in a rock. Describe what you see. (Include information on movement.)  

The atoms in the rock are packed tightly together, with almost no motion. Atoms are next to one another in fixed positions and do not slide past one another or bounce off of each other.

400

Two objects are the same size, but one sinks in water and one floats. They are both made of solid material with no holes. Explain why one floats and one sinks. (Hint: use scientific terms!) 

The object that sinks has more matter in it than the one that floats, so the higher mass makes it sink. It is less buoyant.

400

Explain, in terms of particle movement and energy, why an amount of matter in a gaseous state takes up more space than the same amount of matter in a liquid state.

Gas particles have higher energy and move much faster, so they hit one another and need to spread out. Particles in liquid move slower, so they sit closer together and slide past each other slowly.

400

Oil and water are mixed together, but the oil floats on top instead of blending in. Is this a solution? What does that tell you about whether the substances kept their individual properties?

Not a solution: the oil and water stayed visibly separate and each kept its own properties, which is why you can still see two distinct layers instead of one blended-together liquid.

400

A large piece of wood and a tiny pebble have the same mass. The large wood floats, and the pebble sinks. Which has the greater volume?

large wood: buoyancy does not change the fact that both have the same mass and are made of the same "amount" of "stuff", the wood's "stuff" is just spread through a larger volume

500

I have a big bottle of Purple Air gas. If I open the Purple Air bottle in a small room and leave it open, what will happen to the Purple Air molecules and the molecules in the room's air?

The Purple Air molecules will mix with the room's air molecules and fill the room (which is now the container). 

500

Your ice cube melts into a tiny puddle, then the water fully evaporates. Describe what is happening to the energy and the particles at each step (solid→liquid, then liquid→gas).

solid→liquid: energy is added to fixed particles from heat, so solid particles gain movement as the ice melts into a liquid

liquid→gas: more energy is added to the liquid particles, enough that they can bounce out of the liquid puddle and become gas

500

A student says, "Once you mix two substances together, they're no longer the same substances — they've become something new." Is the student correct when describing a mixture? Explain why or why not.

No: in a mixture, the substances are combined but not chemically changed, so each one keeps its own original properties and could theoretically be separated back out.

500

A scientist says, "Atoms are like tiny building blocks." Explain what this comparison means and why it's a useful way to think about matter.

Everything is made of small basic parts. Even though the finished "structures" (objects) look very different from each other, everything is made of atoms arranged in different ways.