Unit 1 Flashcards
isotopes
atoms of the same element with different masses
example of an isotope
U-235
average atomic weight
average weight of a naturally occurring mixture of an elements isotopes
When determining average atomic weight we consider the ____ of the isotopes as found in nature
percent
where do electrons exist
only in certain areas outside the nucleus called energy levels
how many energy levels are on the periodic table
7
what do protons determine ?
the identity of the element
what is the atomic number
number of protons
what is the atomic mass
mess of the nucleus (protons plus neutrons)
Comes from the Average of the abundance in isotopes
how to find neutrons
mass #- atomic #
on the left which numbers go on top/bottom?
top is the mass
bottom is the atomic #
ions
atoms with a charge
do protons equal electrons in ions ?
noo
if its a negative charged ion you,,,
add electrons
if its a positive charged ion you…
remove electrons
