| A | B |
|---|
| element | a substance that cannot be broken down into simpler substances |
| electron | negatively charged particles that surround the nucleus of an atom |
| proton | positively charged particles found in the nucleus of an atom |
| neutron | particle found in the nucleus of an atom that had no charge |
| electron cloud | region surrounding the nucleus that contains the electrons |
| atomic number | number of protons in the nucleus of an atom |
| nucleus | center of the atom containing protons and electrons |
| atomic mass | is the number of protons and neutrons in the nucleus of an atom |
| periodic table | an organized table of all the elements arranged by properties |
| metal | element that is shiny and conducts electricity |
| non-metal | element that is dull and does not conduct electricity |
| atom | smallest particle of a nelement that has the properties of the element |
| molecule | two or more atoms joined together; the smallest unit of many substances |
| compound | a substance made up of atoms of more than one element joined together in a molecule |
| mixture | two or more substances that are mixed together, but can be separtated out because their atoms are not combined |
| solution | a mixture in which substances break up into their most basic particles, which are too small to be seen and spread evenly through another substance |
| physical property | a way of describing an object using traits that can be observed or measured without changing the substance into something else |
| physical change | a change in one or more physical properties |
| chemical property | describes the way a substance reacts with other substances |
| chemical change | a change that produces new substances with new properties |
