States of Matter
What are the three main states of matter?
Solids, liquids, gases
What is a physical property?
Can be observed without changing the substance
Which property depends on the amount of substance — mass or color?
Mass (extensive)
What type of change is melting butter?
Physical
What is an exothermic reaction?
One that releases energy (feels warm)
Which state of matter has particles packed tightly in a fixed shape?
Solid
What is a chemical property?
Describes how a substance reacts or changes into a new one
Is density intensive or extensive?
Intensive
Burning wood is what type of change?
What is an endothermic reaction?
One that absorbs energy (feels cold)
What happens to particle movement when a liquid turns into a gas?
They move faster and spread apart
Is flammability a physical or chemical property?
Chemical
Explain why volume is an extensive property.
It changes when the amount of matter changes
What are two clues that a chemical change has occurred?
Color/odor change, gas formation, precipitate, or temperature change
Fireworks are an example of which type of reaction?
Exothermic
True or False: Gases have a definite shape and volume.
False
Give one example of a physical property that can be measured.
Density, melting point, mass, etc.
True or False: Boiling point changes if you have more of the same liquid.
False
When sugar dissolves in water, is it a physical or chemical change?
Physical
Ice melting is an example of what kind of process?
Endothermic physical change
Name one example of a physical change involving a change in state.
Melting ice, boiling water, freezing juice, etc.
What property describes how harmful a substance is to living things?
Toxicity
Identify one pair of intensive and extensive properties.
Intensive: color; Extensive: volume
When iron rusts, is the change reversible? Why or why not?
No; a new substance (iron oxide) is formed
A chemical reaction makes the beaker feel cold. What type of reaction is this, and why?
Endothermic; it absorbs energy from surroundings