STATES OF MATTER
What state of matter has a definite shape and volume?
Solid
What process occurs when a solid changes into a liquid when heat is added?
Melting
What is all matter made of?
Molecules
What does it mean when a solid dissolves in a liquid?
The molecules of a solid breaks into tiny particles and mixes and attracts to the liquid particles.
What two materials did we mix in our experiment?
Sugar and water
What state of matter takes the shape of its container but keeps the same volume?
Liquid
What process occurs when a liquid changes into a gas when heat is added?
Evaporation
Do molecules stop moving when matter looks still?
No, they are always moving
What substance dissolves in water in our experiment?
sugar
What change happened to the water on the windowsill and why?
It evaporated- because heat was added by the sun.
What state of matter spreads out to fill all the space in a container?
Gas
What is it called when a gas changes back into a liquid when cold is added?
Condensation
In which state of matter do molecules move the fastest?
Gas
What substance evaporated in our experiment?
water
What was left behind after the water evaporated?
sugar solids
Which state of matter do particles move the slowest in?
Solid
What process occurs when liquids turns into solid when cold is added?
Freezing
How are molecules arranged in a liquid?
Close together, but able to move past each other
Why does sugar dissolve in water?
Because water molecules attract sugar molecules
What does this experiment show about dissolving? (What kind of change is it- physical or chemical)
Dissolving is a physical change
Why do solids keep their shape?
Because their particles are tightly packed and strongly attracted to each other
Are changes like melting and evaporation physical or chemical changes?
Physical changes because they do not create a new substance
How does temperature affect molecule movement?
Higher temperature makes molecules move faster.
Colder Temperature makes them move slower.
Does dissolving make the solid disappear forever?
No, the sugar molecules become a liquid. However they will turn back into a solid when the water dissolves.
How do we know the sugar never disappeared?
Because it was left behind after the water evaporated.