Mid-Year Review

Chemistry, Earth History, Infectious Diseases

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

Physical Properties- A characteristic that you can observe without changing the composition of the substance.

Describes how something looks, smells, sounds, tastes, or fells.

Chemical Properties- A characteristic that you can only observe by changing the identity of the substance.

Describes how something reacts with something else.

Physical Change- Any change that does not involve a change in the substances identity.

ex: Solid to liquid

Chemical Change- Any change in matter that results in the formation of a new chemical substance.

ex: Burning wood

Elements- Made up of atoms that is unable to separate into simpler form.

ex: Gold, Titanium, Hydrogen (ect)

Compounds- Made up of two or more atoms of different elements.

ex: Water (H2O), Hexanoic acid (C6H12O2)

Mixtures- Combination of two or more pure substances they are held together by physical forces, not chemical.


Periodic Table- The Periodic Table is a table of all known elements organized by increasing atomic number.

  • Groups- The vertical rows of elements on the Periodic Table
  • Periods- The horizontal rows of elements on the Periodic Table
  • Metals- An element/substance in it's pure state, as distinguished from alloys.
    ex: Gold; Silver; Copper
  • Non-Metals- An element without metallic properties.
    ex: Carbon; Nitrogen
  • Metalliods- An element that has both metallic and nonmetallic properties.
    ex: Silicon; Boron; Arsenic
  • Atomic Number- The number of proton in the nucleus
  • Atomic Mass- The mass of an Isotope of an element.
  • Neutrons- An element particle having no charge

  • Electrons- An element particle that is a fundamental constituent of matter.

  • Protons- Positive charged element particle that is a fundamental of a atomic nuclei.

  • Law of conversation of mass- systems closed to all transfers of matter and energy must remain constant over time.

Earth History

Law of superposition- Rock layers on the top are younger than ones under them.

Index Fossils- A fossil of widely distributed organisms that lived during only one short period.

Ice Core- A cylinder of ice used to determine the characteristics of past climates.

Geologic Time Scale- A system of chronological measurement that relates stratigraphy to time.

Relative Dating- The process of comparing a rock sample to rock layers to determine the relative age of the sample.

Absolute Dating- The process of determining the exact age of a rock by how many years ago it formed.

Half life/Radioactive decay- The amount of time it takes for half of a radioactive substances atoms to decay.

Infectious Diseases

Microorganisms- A small microscopic organism.

  • Virus- A small non-living thing that invades and reproduces in a living cell.
  • Bacteria- Single-celled organisms that lack a nucleus.
  • Fungi- Single-celled organisms that live by decomposing and absorbing organic material.
  • Parasite- An organism that lives on or in another organism of different species.
Epidemic- An out break of an infectious disease that only influences a small population.

Pandemic- A world-wide out break of an infectious disease.

Prevention- Vaccinations[viruses]

Treatment- Antibiotics[bacterial infections]

Biotechnology- The use of living cells {bacteria, ect.} to make useful products.

  • Careers- Microbiologist; Biochemist; Biophysicist, ect.