Mid-Year Review

Chemistry, Earth History, Infectious Diseases, & Lithosphere

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


-Physical Properties:Odor, Mass, Color, State, Density, Volume

-Physical Changes: any change that doesn't involve change the substances chemical identity

-Chemical Properties: Flammability, Reactivity

-Chemical Change: A new color appears, bubbles of gas are formed, Formation of a precipitate

Elements-Made up of one type of atom. Atoms can not be separated into something simpler

Compounds- Are made up of 2 or more elements that are bonded together. Has a chemical formula

Mixture- Combination of 2 or more pure substances that are held together by physical forces, not chemical

Periodic Table: The horizontal rows on the periodic table are called periods, these tell how many levels of electrons the elements have. The vertical columns are called groups, These tell how reactive the elements are.

Group 1-Alkali metals are the most extremely reactive metals and are never found in nature in their pure form

Group 2-Alkaline earth metals are slightly less reactive than alkali metals

Group 3-12 -Transition metals have a moderate range of reactivity and a wide range of properties.

Group 13- Boron group contains contains 1 metalloid and 4 metals. Aluminum is in this group. It is the most abundant metal in the earths crust.

Group 14- Carbon group contains 1 non-metal, 2 metalloids, and 2 metals.

Group 15- nitrogen group contains 2 non-metals, 2 metalloids, and 1 metal.

Group 16- Oxygen group contains three non-metals, 1 metalloid, and 1 metal.

Group 17- All non-metals. Very reactive. Poor conductors of heat and electricity. Tend to form salts with metals.

Group 18- Noble gases- Unreactive non-metals. All are colorless, odorless gasses at room temperature. All found in small amounts in the earths atmosphere.

Atomic number- The atomic number is the same number as the number of protons and electrons.

Atomic mass- The weight of the atom

Neutrons- Round the atomic weight to the nearest whole number ,then subtract the number of protons from the weight.

The law of conservation of mass states that matter cannot be created or destroyed.

Vocabulary Words:

  • Atomic mass
  • Atomic number
  • Physical properties
  • Chemical properties
  • Groups
  • Periods

Earth History

Law of Superposition states that a rock layer is older than one on top of it. This is only applied to rock layers that have not been disturbed.

Index Fossil- A fossil with a known age that helps indicate the age of the rock layer it is located in.

Ice cores-