Matter Matters
What are the three most common states of matter?
Solid, Liquid, Gas
What is the formula for density?
D = M ÷ V (Density = Mass ÷ Volume)
Cutting paper into small pieces — physical or chemical?
Physical
What is a pure substance?
A material made of only one type of particle (element or compound).
What is the smallest unit of an element that still has its properties?
Atom
Which state of matter has no definite shape or volume?
Gas
What is the density of a cube with a mass of 40 g and a volume of 8 mL?
5 g/mL
Burning wood — physical or chemical?
Chemical
What type of mixture looks the same throughout?
Homogeneous mixture
Which type of element is shiny, conducts heat and electricity, and is malleable?
Metal
When a gas changes to a liquid, what process is happening?
Condensation
If an object has a density of 0.5 g/mL, will it sink or float in water?
Float
Name 2 signs that a chemical change has occurred.
Color change, gas/bubbles, temperature change, new substance.
Is trail mix a homogeneous or heterogeneous mixture?
Heterogeneous
What does the atomic mass represent?
Protons + Neutrons
Compare particle movement in solids vs. gases.
Solids vibrate in place; gases move freely and fast.
Two liquids don’t mix. One floats on top. Which one has greater density?
The one on the bottom.
Ice melting in the sun — what type of change?
Physical (change of state)
Salt water is an example of what type of mixture?
Homogeneous (solution)
Which group of elements are dull, brittle, and poor conductors of heat and electricity?
Nonmetals
A balloon left in the sun expands. What causes this change?
Heat increases particle movement (thermal expansion).
True or False: Two objects of different sizes can have the same density.
True
Which type of change forms a substance with new properties?
Chemical Change
Classify each: air, gold, salad, salt → element, compound, homogeneous, heterogeneous.
Air = homogeneous; Gold = element; Salad = heterogeneous; Salt = compound
A student is testing unknown elements. One is shiny, brittle, and can conduct some electricity. What type of element is it?
Metalloid