States of Matter and Phase Changes
Describe the particles of the three states of matter
Solid: Particles tightly packed and dont move
Liquid: Particles loosely packed and move around a little
Gas: Particles are spread out and move freely
Define conductor and insulator
Conductor: A material that light, electrical, heat or sound energy can pass through.
Insulator: A material that conducts electricity, heat or sound poorly.
What tool and units do we use to measure a substance?
Balance (grams)
Ice melting is a...
physical change.
List the 4 phase changes
Freezing, Melting, Condensation and Evaporation.
Define solubility and list 1 soluble material
The amount of a material that can dissolve in a liquid(solvent).
Salt and sugar are soluble.
What tool and units do we use to measure a liquid?
Graduated Cynlinder (mililiters)
Wood burning is a...
Chemical change.
A bottle of water was left in a car overnight. The next day the bottle of water was frozen. What phase change happened overnight and why?
The water in the bottle went from a liquid to a solid, it froze. This happened because it was cold overnight.
Define how to test solubility
Pour the material into a glass of water and mix.
Watch to see what happens, if the material dissolves it is soluble and if the material is still there it is insoluble.
Before mixing vinegar and cream of tartar in a plastic bag the mass was 47 grams. What will be the mass after mixing and why?
The mass should still be 47 grams. This is a closed system so no particles can be added or escape.
Boiling water is a...
Physical change.
After doing an investigation in science the students used wipes to clean off their desks. One student noticed that the desks started off wet but then dried up. What phase change happened and why?
The wipes have liquid in them, which made the desks wet. The liquid particles evaporated and became gas particles.
Define how to test materials for thermal conductivity. Along with that share what it means if the material gets hot or stays cold
Materials can be placed into a bowl with hot water or placed onto a hot surface.
If the material is hot to the touch that means heat can easliy pass through it.
if the material doesn't really get hot that means heat can not easily pass through it.
Water with a mass of 7.9 grams is mixed with 7.7 gams of oil. After the two are mixed, what will be the final mass of the mixture?
What tool can we use to weigh this substance?
15.6 grams
Balance
How do we know that a new substance is being formed?
There could be a temperature change, bubbles or fizzing, a color change, an odor or formation of a solid.
The shower was left running with the hot water on. When someone came to turn it off, the windows and mirrors were foggy. What phase change happened and why.
The phase change is condensation. The hot water created steam/water vapor(gas).That steam touched a cold surface (the mirror) and became a liquid.
Define how to test materials for electrical conductivity. Explain what should happen if it works
Connect the material to a battery and light bulb using cables with clips.
If the material conducts electicity the light bulb will light up.
Before mixing water and baking soda the mass of the bag was 34 grams. After mixing the mass was 33 grams.
What could have caused the loss of mass of the bag?
Something could have spilled while pouring the materials into the bag.
or
There was a leak in the bag causing particles to escape.
Explain why baking bread is chemical change
Baking bread is a chemical change because a new substance is being formed. Once this new substance is formed the materials can not go back to their original state.