equations for chemistry Flashcards
1
Q
average atomic mass
A
atomic mass x percent abundance + atomic mass x percent abundance = average atomic mass
2
Q
percent abundance
A
atomic mass (x) + atomic mass (1-x) = known average atomic mass
3
Q
atomic #
A
number of protons
4
Q
mass number
A
given mass, the # of protons plus the number of neutrons
5
Q
protons
A
same as atomic number
6
Q
neutrons
A
mass # - number of protons
7
Q
electrons
A
look at net charge and number of protons
8
Q
does number of protons change in an element
A
NO
9
Q
if an element had a +4 charge ?
A
4 more protons then there are electrons
10
Q
if an element had a -4 charge
A
4 more electrons then there are protons
11
Q
in iodine-131 what is 131
A
the mass number
