Give an example of a physical property that can be measured.
Mass, Length, Volume, etc
Cutting your hair is an example of what type of change?
Physical change
What is a mixture?
2 or more substances blended together that can be separated by physical means
What defines a substance in chemistry?
matter with uniform composition that cannot be physically separated
Which of the following is a chemical property of a substance?
Melting point, Density, Reactivity, Color
Reactivity
Give an example of each a reversible and a irreversible change.
Reversible: Melting, Freezing, Boiling
Irreversible: Tearing, Crushing, Chopping
Differentiate between homogeneous and heterogeneous mixtures.
Homogenous: Evenly mixed
Heterogenous: Unevenly mixed
What is the main difference between elements and compounds?
An element is a pure substance consisting of only one type of atom. It cannot be broken down into simpler substances by chemical means.
A compound is more than one element bonded together.
What is the difference between a physical property and a chemical property?
Physical properties are observed without altering the substance's chemical identity, while chemical properties involve changes of a substance to a different substance
What is the definition of a physical change?
Change that does not alter the identity of the substance
Provide an example of a solution
Kool aid, Salt water, Brass, Soda
Give an example of an element that is not on the periodic table
It does not exist
What is the difference in an intensive and extensive physical property?
Intensive: Doesn't depend on amount of material
Ex: Color, Density, Freezing point
Extensive: Does depend on amount of matter
Ex: Mass, Length, Volume
Describe a chemical change and provide an example.
Occurs when one substance changes into another
Give 3 ways mixtures can be separated
Filtration, Evaporation, Distillation, Handpicking, Magnet, Sieving
What is the difference in an atom and a molecule?
Atom is the smallest unit of an element. Molecule is the smallest unit of a compound, and is more than one atoms bonded together.
Define density and explain how it can be used to identify substances.
Density is mass per unit volume. An unknown substance could be identified by finding its density, and comparing to already known densities.
What are at least 2 signs of a chemical reaction?
odor, heating/cooling, change in appearance, light or sound, formation of bubbles.
How would you separate a mixture of water, rock and sand
Use a sift to remove the rock, then filter the sand from the water.
Which is not an element: Gold, Neon, Lead, Steel, Krypton, Americium, or Mercury
Steel