| A | B |
|---|
| mass number | antimony's is 122 |
| Moseley | improved original periodic table |
| neutrons | particle discovered by chadwick |
| radioactive | type of atoms used by archaeologists to study ago of fossils |
| malleable | pounded into sheets |
| element | made up of one type of atom |
| isotopes | atoms of same element that have different number of neutrons |
| alkali | group I metals |
| energy levels | there are 7 of these also called shells |
| Ca | symbol for the element that hardens teeth enamel |
| Na | symbol for element ionically bonded to chlorine to form table salt |
| noble gases | nonreactive group on nonmetals |
| ductile | drawn into wire |
| nucleus | twice the mass of the protons and positively charged |
| periodic table | has elements arranged by increasing atomic number |
| electron cloud | location of electrons in an atom |
| atomic number | iodine's is 53 |
| arsenic | poisonous metalloid |
| average atomic mass | weighted mass of all isotopes of an element |
| family | group or column's name |
| mercury | only liquid metal |
| sixteen | mass number of oxygen |
| halogens | group between oxygen and neon |
| quarks | particles that make up protons and neutrons |
| atomic model | started out as a solid sphere by Dalton but changed by Bohr |
| Mendeleve | founder of periodic table |
| protons | subtract these from mass number to get neutrons |
| electrons | equal the number of protons in a neutral atom |
| semiconductors | metalloid property |
| Rutherford | discovered protons |
| eight | number of electrons in second shell |
