| A | B |
|---|
| atom | the smallest part of an element |
| nucleus | the center or core of an atom |
| proton | equal to the atomic number and found in the nuceus |
| proton | found in the nucleus and has a positive charge |
| neutron | found in the nucleus and has no charge |
| electron | has a negative charge |
| electron | spins around the nucleus in orbits |
| atomic number | equal to the number of protons |
| atomic mass | the mass of the nucleus |
| atomic mass | the number of protons plus the number of neutrons |
| periodic table | a chart that organizes elements according to atomic number and properties |
| metals | good conductors of heat and electricity |
| metals | located on the left side of the periodic table |
| periods | rows on the periodic table |
| families | columns on the periodic table |
| on the periodic table, row numbers = | the number of orbits |
| on the periodic table, column numbers = | electrons in the outer orbit |
| valence electrons | electrons in the outer orbit |
| physical change | changes the form, but does not make a new substance |
| chemical change | makes a new substance with different properties |
| mass | the amount of matter in an object |
| Who first organized the periodic table? | Mendelev |
| What does location on the periodic table help to predict? | characteristics / properties |
| metalloids | touch the border of metals and non-metals; they have characteristics of both |
| halogen family | includes flourine, chlorine and bromine (group 17 / 7 valence electrons) |
| noble gas family | 8 valence electrons; non-reactive, do not form compounds |
| ductile | can be pulled into a long, thin shape like wire |
| malleable | can be pounded or pressed into thin sheets |
| conductivity | electricity or heat can move through the material |
| transition metals | contain familiar metals like gold, silver, tin, copper |
| What state are most metals found at room temperature? | solid |
| reactants | substances on the left side of a chemical equation |
| products | substances on the right side of a chemical equation |
