| A | B |
|---|
| atom | tiny building blocks of matter, made up of protons, neutrons, and electrons |
| atomic number | the number of protons in an atom |
| compound | matter that is made of two or more elements and has physical and chemical properties different from each of the elements that make it up |
| density | physical property of matter that can be determined by dividing the mass of an object by its volume |
| electron | negatively charged particles that move around the nucleus of an atom and form an electron cloud |
| element | substance that contains only one type of atom - for example oxygen |
| ion | electronically charged atom whose charge results from an atom losing or gaining electrons |
| isotope | atoms of the same element that have different numbers of neutrons |
| heterogeneous mixture | a mixture which is not mixed evenly and each component retains its own properties |
| homogeneous mixture | a mixture which is evenly mixed throughout |
| mass number | the number of protons plus the number of neutrons in an atom |
| matter | anything that has mass and takes up space |
| mixture | describes two or more substances that retain their own properties even when they are combined and taht can be separated from one another by physical means |
| neutron | particle without an electric charge that is located in the nucleus of an atom |
| proton | postively charged particle that is located in the nucleus of an atom |
| solution | a kind of mixture in which one substance is ocmpletely and evenly mixed in another substance and is the same throughout |
| chemical properties | describes a change that occurs when one substance reacts with another |
| density | mass divided by volume |
| physical properties | properties you can observe without changing a substance into a new substance |
| solid | state in which atoms are strongly attracted and do not change positions |
| plasma | the most common state of matter in the universe |
| gas | state in which a substance completely fills its container |
| liquid | state in which matter flows as it takes the shape of a container |
