GCHEM 111

protons
- positive
- mass= 1.672623 x 10^-24g
- relative mass= 1.007 atomic mass units (u)
electrons
- negative
- relative mass = 0.0005 u ( not usually counted because they are so light)
neutrons
- no charge
- mass= 1.009 u
atomic number
"Z"
- main number
- order in periodic table
- not weight!
- is the number of protons and electrons
atomic weight/mass

protons + neutrons
standard=

carbon
isotopes

atoms of same element, but different mass number
average mass=

atomic weight
if you change the mass number you change...

the number of neutrons
numbers in the periodic table in terms of mass are not....

exact they are averages
finding atomic weight with isotopes

(% of isotope 1)(mass) + (% of isotope 2)(mass)= average weight

Author

akcinloor

175152

Card Set

GCHEM 111

Description

chapter 2

Updated

2012-10-03T01:49:46Z

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