Mid-year review

earth history infectious diseases and chemistry

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

Physical properties is a characteristic that can be observed without changing the identity of the substance. examples of physical properties is color and shape and texture and smell and size and state of matter.

Chemical properties:is a characteristic that you can only observe by changing the identify of the substance. examples of chemical properties is flammability and re activity and oxidation. Matter can't be created or destroyed but matter can be changed. matter changes physically and chemically.

A physical change- Is any change NOT involving a change in the substance's chemical identity. b

Examples of Physical change:Chopping wood mixing red and green marbles.

A chemical change-one or more substances are changed into new substances. Examples:A explosion of fireworks. Mixing acid and a base. Baking a cake. Milk going sour

Element: elements are arranged on the periodic table.

Compounds: two or more atoms of different elements that are bonded together made of elements in a specific ratio that is always the same has a chemical formula can only be separated chemically but not physically.

Mixtures:a mixture is a combination of 2 or more pure substances that are held together by physical forces and chemical.

periodic table: is a table that shows all the elements arranged in order by the atomic number. They usually are in rows.


groups 1 is alkali metals and group 2 is alkaline earth metals

group three through twelve is transition metals

Lanthanides and Actinides are placed on the bottom of the periodic table.

Metals are placed in group 1 and 2. Non-metals are in row 14 15 16 17. Metalloids are placed in elements 5 and 14 and 32 and 33 and 51 and 52 and 85.

A atomic number- is the number of the elements. Atomic mass is the same number of the protons and neutrons in the atom.

protons and the neutrons will stay the same.


The law of superposition is a key axiom based of observations of natural history.

Index fossil is a fossil that is useful for dating and the correlating the strata in which it is found.

Ice cores-is a sample of ice that can tell you the past dimate by holding carbon dioxide.

Geologic Time Scale: is a system of chronological measurement that relates stratigraphy.

Relative dating:the age of a rock compared to the ages of rock layers.

Absolute dating: the age of a rock given as the number of years since the rock formed.

half-life: is the time taken for the radioactivity of a specified isotope to fall to half its original value.

Radioactive Decay: is the spontaneous breakdown of an atomic nucleus resulting in the release of energy and matter from the nucleus.

Vocabulary: Geology

relative dating

absolute dating

index fossil

law of superposition

ice core

Infectious diseases:

They are different types of microorganisms that include viruses and bacteria and protozoa and parasites and fungi and algae

epidemic is a widespread occurrence of an infectious disease in a community at time.

pandemic:is a prevalent over a whole country or the world like the movie contagion.

How to prevent you got wash your hands and good hygiene.

biotechnology is the use of living cells bacteria to make useful products