States of Matter
What are the three main states of matter?
Solids, liquids, and gases
Is melting ice a physical or chemical change?
Physical change
What tool do we use to measure the mass of an object?
A balance (or scale)
True or False: Matter can be created or destroyed.
False — matter cannot be created or destroyed
Matter is anything that has __________ and takes up __________.
Matter has mass and takes up space
Give one example of a solid, one liquid, and one gas.
Examples will vary: Solid (rock, ice, pencil), Liquid (water, milk, juice), Gas (air, helium)
Name one sign of a chemical change.
Possible signs: gas bubbles, change in color, new smell, heat or light produced, new substance formed
Which physical property describes how shiny something is?
Reflectivity
When a solid melts, does the total amount of matter change?
No — the matter just changes form (solid to liquid), but the amount stays the same
What do we call how well a material dissolves in water?
Solubility
How are the particles spaced in a solid compared to a gas?
The particles in a solid are tightly packed together and vibrating in a fixed place and gas particles are far apart and moving quickly.
Is dissolving salt in water a physical or chemical change? Explain.
Physical change — the salt is still salt, it can be separated, no new substance is made
A magnet sticks to one object but not another. What physical property is being tested?
Magnetism (or magnetic property)
You break a chocolate bar into pieces. What happens to the total mass?
The total mass stays the same because all the pieces still equal the original chocolate bar.
What is a conductor?
A conductor is something that allows heat or electricity to pass through it easily.
Why does a liquid take the shape of its container, but a solid does not?
Liquids take the shape of their container because their particles can slide past each other. Solid particles are packed tightly and stay in place.
Baking a cake changes the batter into a new substance. Why is this a chemical change?
Chemical — the dough changes into something new when heated (new smell, new substance, cannot change back)
Why is measuring mass important when comparing two objects?
Mass helps us compare how much matter is in each object. The heavier object has more mass.
Vinegar and baking soda fizz in a closed container. Why does the total mass stay the same?
The total mass stays the same because nothing leaves the container — all gas stays inside.
What is a mixture? Give one example.
A mixture is two or more substances mixed together but not chemically changed. Example: trail mix, sand and water
A student says air is “nothing.” Use evidence to explain why air is matter.
Air is matter because it has mass and takes up space (balloons fill with air, air can be weighed, etc.)
A student sees sugar burn and turns black. Explain why this is a chemical change using evidence.
This is a chemical change because burning sugar creates a new substance. The sugar changes color to black and cannot be changed back into sugar. The heat causes it to react and form something new, so it’s a chemical change.
What tool is used to measure volume, length, and weight?
and
List 5 different properties of matter besides the ones listed above.
Volume is measured with length x width x height or displacement for irregular sized objects. Length is measured with a metric ruler or a meter stick. Weight is measured using a balance or scale.
Possible properties of matter: size, shape, color, material, magnetism, reflectivity, flexibility, state of matter, solubility, hardness, melting point, boiling point, freezing point, conductivity, density, odor,
A student heats water until it evaporates and says the water is “gone.” Explain why the water did not disappear.
The water changed to a gas (water vapor), not disappeared. The total matter stayed the same.
What is the difference between a mixture and a solution? Give two differences.
A mixture can be separated easily and each part keeps its own properties. A solution is a special mixture where one substance dissolves in another and cannot be easily seen or separated.