Science vocab atoms and protons

Densit

The mass of an object divided by its volume

Matter

Anything that has mass and takes up space and is made up of different kinds of atoms; includes all things that can be seen, tasted, smelled, or touched but does not include heat, sound, or light

Atom

A very small particle that makes up most kinds of matter and consists of smaller parts called protons, neutrons, and electrons

Law of conversation of matter

States that matter is not created or destroyed but only changes its form

Electron

Invisible, negatively charged particle located in a cloudlike formation that surrounds the nucleus of an atom

Nucleus

Organelle that controls all the activities of a cell and contains hereditary material made of proteins and DNA; positively charged, central part of an atom

Proton

Positively charged particle located in the nucleus of an atom and that is counted to identify the atomic number

Neutron

An uncharged particle located in the nucleus of an atom

Mass

a measure of the amount of matter an object has

Element

Natural or synthetic material that cannot be broken down into simpler materials by ordinary means; has unique properties and is generally classified as a metal, metalloid, or nonmetal

Atomic number

Number of protons in the nucleus of each atom of a given element; is the top number in the periodic table

Isotope

Two or more atoms of the same element that have different numbers of neutrons in their nuclei

Mass number

Sum of the number of protons and neutrons in the nucleus of an atom

Atomic mass

average mass of an atom of an element; its unit of measure is the atomic mass unit, which is 1/12 the mass of a carbon-12 atom

Metal

Element that is malleable, ductile, a good conductor of electricity, and generally has a shiny or metallic luster

Metalloid

Element that has characteristics of both metals and nonmetals and is a solid at room temperature