Mid-year science review
Chemistry, Earth History, Infectious Diseases
A Periodic Table is a table of chemical elements arranged by order of Atomic Number. It is sorted from left to right, from least reactivity to most.
Contents of a Periodic Table-
Atomic Number: A number which is equal to the number of protons in the nucleus. This helps identify elements. The Atomic Number is located above the element letter.
Protons: A particle within a nucleus which has a positive electrical charge.
Neutrons: A particle within a nucleus which has no electrical charge.
Electrons: A particle which orbits the nucleus which has a negative electrical charge.
Groups: Columns of elements on the periodic table that share common properties.
Periods: Horizontal rows on the periodic table which share common properties.
Law of Conservation of Mass: The principal of the Law of Conservation of Mass states that matter cannot be destroyed nor created, and can only be transferred from state to state.
Elements: Substances which cannot be broken down into a simpler form, All known elements are listed on the Periodic Table.
Compounds: The result of two or more elements combining chemically.
Mixtures: The result of combining two things but them not combining.
Physical/Chemical Properties: Physical properties can be changed or measured without changing what is being studied, Chemical properties can only be observed during a chemical reaction.
Physical/Chemical Change: Physical changed do not form a new substance, while chemical changes change one or more substances into new substances with new properties.
Flammability- The ability of something to catch fire
Reactivity- The amount of reactiveness something has with other elements
Atoms- The basic building blocks of matter
Matter- Everything that exists
The Law of Superposition basically states that any any rock layer is older than the one above it.
Relative Dating: This type of dating is used to find a time era which a fossil is from by comparing that fossil's location/depth with that of other fossils of similar accordance.
Absolute Dating: This type of dating puts an exact date on how many years old a fossil is, which is proven by science at a molecular level, usually found by study of radioactive decay.
Half-Life: The amount of time it takes for half of the molecules of a sample of a once-living organism's fossil to die due to radioactive decay.
Radioactive Dating: Uses Half-Life to determine the amount of time a fossil has been decaying, therefore, roughly, the amount of time the fossil has existed in a nonliving state.
Index Fossils: Usually-common fossils which are used to determine the relative date of other fossils within the same rock layer.
Geologic Time Scale: A time scale of each era of earth's history, used by geologists, paleontologists, and others which study earth history or related fields.
Ice Cores: Ice which is deep within Antarctic ice sheets and holds gas traces and other useful sources of information on the atmosphere of it's time.
Carbon dating- A scientific way of using the elements which are in the fossil or rock surrounding it to help determine the exact age of the fossil.
Isotopes- Different versions of the same elements, Scientists use isotopes for relative dating.
Fossil record- A record of the total number of fossils that have been discovered
Fossil- The trace or remains of an organism which lived long ago.
Igneous- Created from cooled magma
Metamorphic- Created from heat and pressure
Sedimentary- Created from compaction and sedimentation of sediments
- Virus- An infective agent only able to multiply within a host cell. Nonliving.
- Bacteria- Tiny microorganisms which can cause disease.
- Fungi- Microorganisms which can spread by spores and cause diseases like ringworm.
- Parasite- Can range from a microorganism to a small animal, living organisms which feed off of other living organisms to survive.
Epidemic: A widespread occurrence of a disease within a certain society, country or community at a certain time.
Pandemic: A widespread occurrence of a disease that is spread throughout multiple countries, regions or even continents.
How to prevent: Washing hands, living in clean conditions, eating well prepared food, getting vaccinated.
Biotechnology: The use of organisms to create useful products.