Science Terms-Ch. 4

anything that has mass and takes up space

• a small particle that makes up most types of matter

matter is not created or destroyed- it only changes form

negatively charged particles, subatomic particles---they surrounds the nucleus of an atom

• -the positively charged central part of an atom

• -the posively charged particles in the nucleus of an atom----also what is counted to identify the atomic number

• -uncharged particles located in the nucleus of an atom

-matter made of only one kind of atom

-the number of protons in the nucleus of each atom of a given element; it's the top number in the periodic table

• -two or more atoms of the same element that have different numbers of neutrons in their nuclei.

-the number of protons plus the number of neutrons it contains.

• -the sum of the number of protons and neutrons in the nucleus of an atom

• -the average mass of an atom of an element

-and element that is malleable, ductile, a good conductor of electricity and generally has a shiny or metalic luster.

-elements that are usually gases or brittle solids and poor conductors of electricity and heat; are the basis of chemicals of life

-elements that have characteristics of both metals and nonmetals and is a solid at room temperature

-matter that has the same composition and properties throughout

Examples: a bar of gold (all gold), a sheet of aluminum (all aluminum)

-a substance produced when elements combine and whose properties are different from each of the elements in it

• Examples: Water (H2O), Hydrogen peroxide (H2O2), carbon dioxide (CO2)

-a combination of compounds and elements that has not formed a new substance and whose properties can be changed without changing the mixture's identity

Examples: water and sand in bucket, air, our blood

• -a mixture that has larger parts that are different from each other.
• Examples: oil and water, water and sand.

-a mixture that is the same throughout

• Examples: air, water