States of matter
What are the three main states of matter?
Solid, liquid, gas
What are the tiny bits that make up all matter called?
Atoms and molecules / particles
What is mass?
The amount of matter an object has
In a marble vs. foam ball in water activity, which one sinks and why?
Marble sinks because it is denser than water
True or False: Matter is anything that has mass and volume.
True
Give one example of a solid, one example of a liquid, and one example of a gas found in the classroom.
desk - solid; water bottle water - liquid; air - gas
What is a molecule? Give the water molecule example.
A group of atoms bonded together; water = two hydrogen + one oxygen = H2O
What is volume?
The amount of space an object takes up
If syrup is poured into water and sinks, what does that tell you about syrup’s density compared to water?
Syrup is denser than water
True or False: Air is not matter because we cannot see it.
False — air has mass and volume
Which state of matter has particles tightly packed in an orderly arrangement and holds its shape?
solid
What does “attractive forces” between particles mean?
Forces that pull particles toward each other; stronger in solids, weaker in liquids, weakest in gases
Match the object to the best SI unit: paperclip, bag of apples, measuring spoon, milk carton.
paperclip — grams (g); bag of apples — kilograms (kg); measuring spoon — millilitres (mL); milk carton — litres (L)
You have two same-size balls: clay and cotton. Which is denser and why?
Clay is denser because its particles are packed more closely
True or False: Liquids have a definite volume but not a definite shape.
True
Explain how water can be in all three states of matter; name each state and an example.
Ice — solid; liquid water — liquid; steam — gas
Compare particle motion and attractive force in a diamond, orange juice, and air.
Diamond — very strong attraction, particles tightly held; orange juice — weaker attraction, particles closer but move more; air — weakest attraction, particles far apart and move fast
Define density in one sentence.
Density is how closely packed the particles/matter are in a given volume
What will happen if you drop a small piece of sponge and a small rock of the same size into water?
The rock will likely sink and the sponge will likely float because the rock is denser than the sponge
True or False: In solids, particles move quickly and are far apart.
False — particles move slowly and are close together
Describe what happens to particle arrangement and movement when a solid becomes a liquid (melting).
Particles move faster and become less orderly; they are still close but can move past each other
Develop a short model explanation: why can you compress gas more easily than a rock?
Gas particles are far apart so they can be pushed closer (compressible); rock particles are tightly packed and strongly attracted so not easily compressed
Name one tool you could use to measure mass and one tool to measure volume.
Mass — balance or scale; Volume — graduated cylinder or measuring cup
Which floats on water — oil or water — and why?
Oil floats on water because oil is less dense than water
True or False: Two objects of the same size must have the same density. Explain your answer.
False — they can have different densities depending on how tightly packed their particles are; e.g., clay vs cotton