Mid-Year Review

Chemistry, Earth History, Microorganisms, and Lithosphere

Chemistry-8.O.1- Understand the properties of matter and changes that occur when matter interacts in an open and closed container

Physical properties

  • Odor
  • Mass
  • State
  • color
  • Volume
  • Density
Can be observed with out any change happening
Chemical properties

  • flammability
  • re-activity
These properties can be observed during a chemical reaction. Describes matter on its ability to change into new matter with different properties.

Physical and chemical changes

Physical Change

  • Boiling water
  • wood chipping
  • Ice melting
Any change that does not involve a change in the substance's chemical identity.

Chemical Change

  • New color appears
  • Heat, Light, or sound is given off
  • Bubbles of gas are formed
  • Difficult or impossible to reverse
Any change in matter that results in the formation of new chemical substance.

Elements, Compounds and Mixtures

Elements- Made of one type of atom. Cannot be separated into a simpler substance by physical or chemical means

Compounds- Are made of 2 or more atoms of different elements that are chemically combined. They can only be separated by chemical means.

Mixtures- Combination of 2 or more pure substances that are held together by chemical mmeans

periodic table

Group- the vertical rows on the periodic table

Periods- The horizontal rows on the periodic table

The periodic table in broken into sections of Metals, Metalliods, and Non- Metals

The metals are on the left side of the periodic table and they contain the most metal properties.The metalliods are elements that are have an intermediate amount of metal and non- metal properties. Non- Metals are on the far right side of the periodic table and they are elements that contain no metal properties.

Atomic Number- The number of protons in an element

Atomic Mass- The mass of an atomic particle

Protons- The amount of positive charge in an atom

Neutron- A particle in the atom with about the same mass as the protons but lacking a charge

Electron- A particle within an atom with a negative charge

Law of Conservation of Mass- This law states that Matter can neither be created or destroyed yet it can only be transferred

Vocabulary- Solution, matter, compound, atom, mixture,element,


Law of Superposition- Younger rocks are above older rocks in an area of undisturbed rock

Index fossils- A fossil in a rock layer of one geologic age and is used to establish the age of the rock layers

Ice Core- A cylinder of ice that tells us about some characteristics of Earth's history

Geologic Time Scale- A measurement of time that connects the relationship of time and some of the major events in Earth's past

Absolute Dating- The exact age of a rock/ fossil ect.

Relative Dating- Used to determine the age of a fossil by its position in sedimentary rock

Half life/ Radioactive Decay- The time required for an isotope to loose half of its original value

Vocabulary- Absolute dating, Relative dating, Half life, law of superposition, geology, fossil, Index fossil, geologic time scale


Microorganism- A microscopic organism, such as bacterium, fungi, and viruses

Virus- A non- living microscopic agent that invades and destroys healthy cells

Bacteria- Microscopic agents that are prokaryotic that cause disease

Fungi- A large group of eukaryotic organisms