This property describes whether an object will sink or float
Relative Density
A salad is an example of this type of mixture
A mixture where substances maintain their physical properties
The salt dissolves, but the matter is still there
This invisible matter is inside of a balloon
Gas particles
Which has mass? Gas or light
Gas has mass, light does not
This physical property describes whether a substance allows energy to flow
Conductivity
In a mixture of sand and iron filings, this tool would be best for separating them
A magnet
This tool could be used to show that the mass of a solution is the same as the mass of both substances combined
A triple beam balance or digital scale
True or False: An empty glass actually has no matter inside.
False — it contains gas (air), which is matter
True or False: In a mixture, the substances lose their properties.
False - In a mixture, the substances maintain all of their physical properties
Two cubes the same size are placed in water. One sinks and one floats. Why is the sinking cube more dense than water?
Because it has more mass packed into the same volume, making its density greater than water’s.
Salt water is an example of this type of mixture
A solution where the substances maintain some of their physical properties
This is an example of a solution where matter is conserved
Sugar + Water
Lemonade mix + water
etc.
When you put a balloon in cold water, the balloon changes shape. This happens to the air particles inside
They are condensed closer together.
Kool-Aid powder in water is this kind of mixture
A student says wood is a good conductor of electricity. Use evidence to explain whether they are correct.
No, wood is an insulator. Conductors (like metals) allow electricity to flow; wood does not.
Two students argue: one says sugar water is just a mixture and can be separated with a filter the other says it’s a solution. Who is correct and why?
The second student; sugar water is a solution because the sugar dissolves and cannot be easily separated without evaporation.
You mix 50g of salt with 200g of water. The solution “looks smaller” than the separate parts. Has matter been lost? Explain with evidence.
No, the mass is still 250g. Salt dissolves but doesn’t disappear—matter is conserved.
Explain why an inflated basketball feels heavier than a deflated basketball.
It has more gas particles packed inside, adding mass.
A student mixes salt and sand together. Another mixes sugar into water. Compare the two mixtures using physical properties.
Salt + sand is a mixture where each substance keeps its properties and can be separated easily (e.g., magnet/filtration). Sugar + water is a solution where sugar dissolves, changing the appearance but conserving matter.
A student wants to investigate which materials are best at insulating heat. This is how they should test it and what they should measure
Wrap cups with different materials (cloth, foil, plastic, etc.), add hot water, measure temperature change after 10 minutes. The material that least change in temperature is the best insulator.
How would you separate a mixture of sand, salt, and iron filings?
Use magnet to remove iron, add water to dissolve salt, filter out sand, evaporate water to get salt.
How would you prove matter is conserved when sugar dissolves in water. What tools would you use and what data would you collect?
Use a balance to measure mass before and after mixing; record that total mass stays the same.
When a balloon is left in the sun, it gets bigger. This is why that happens
The gas particles inside gain thermal energy, move faster, and spread farther apart, causing the balloon to expand.
When sugar dissolves in water, you can’t see the sugar anymore. Using the particle model of matter, explain why the sugar has not disappeared.
The sugar particles break apart and spread evenly among the water particles. They are too small to see, but they are still present, and the total mass stays the same.