| A | B |
|---|
| ion | When an atom gains or loses one or more electrons and becomes charged |
| isotope | atoms of an element that have the same #p but diff. #n |
| Mass # | # of p and n in an stom (p+n=mass #) |
| isotopes | have same atomic # but diff. mass # |
| Atomic mass | the average of the atoms in an element (mass# +mass #/ 2 =Atomic mass) |
| mole | amount of a substance containing Avogadro's # of "atoms" |
| Mole # | 6.02 x 10^23 |
| Atomic mass Unit (amu) | 1/12 of the carbon-12 atom. Average mass of p/n |
| Nucleus | small dense core at the center of an atom |
| contains most mass | nucleus |
| energy (cloud) | area around the nucleus in which electrons reside. |
| atom's volume (size) | energy cloud |
| electrons | neg. charge |
| neutrons | nutral |
| protons | pos. charge |
| atom | smallest part of an element that retains the chemical identity of that element |
| size of an atom | 1 X 10^ -10 meter to 5 X 10^ -10 |
| mole to grams | mole= 1; grams=atomic mass (amu) |
| mole to atom | mole=1; atom=6.02 X10^23 |
| grams to atom | grams=atomic mass (amu); atom=6.02X10^23 |
