states of matter
what is matter?
Matter is anything that has mass (weight)
and takes up space.
occurs when a liquid becomes a gas.
Evaporation
thermal energy
is the energy in an object due to the movement of its molecules and atoms.
is any property that is evident without a chemical reaction.
physical property
what is a chemical property?
A chemical property is a property that becomes
evident during, or after, a chemical change.
All matter is made of tiny particles called
atoms
occurs when a gas becomes a liquid.
Condensation
Particles that move quickly have a
lot of thermal energy.
occurs when a substance changes states without changing what the substance is.
physical changes
______are different from physical properties because they require a chemical change for the property to be observed.
chemical properties
have particles that are packed together very tightly. There is very little space between them.
solids
occurs when a solid becomes a gas.
Sublimation
particles that move slowly
do not have a lot of thermal energy.
Physical changes are __________. That means they can be undone.
reversible
Chemical changes result in the production of____
of a new substance and cannot be reversed.
have particles that are packed together more loosely than solids, but more densely than gases.
liquids
occurs when a gas becomes a solid.
Deposition
When an object is cooled, it______ thermal energy.
loses
Melting a chocolate bar
Freezing an ice cube
Dissolving sugar in water
are examples of what?
Physical changes
Some clues may help determine whether a chemical
change has occurred. Name the clues.
colour changes, production of an odour, temperature changes, creation of a gas, and formation of a solid.
have particles that are more spread apart than both solids and liquids. These particles move freely at high speeds
gases
occurs when a liquid becomes a solid.
freezing
When an object is heated, it ______ thermal energy.
gains
Explain why cutting down a tree is a physical change.
Cutting down a tree is a physical change because the tree is not chemically altered. The chopped wood is
still wood.
Give an example of a chemical change that could be done to a tree.
burning