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Masses of Atoms
Pages 550 - 553
Element ~ matter that is unique from all others, because of different numbers of protons.
Element ~ matter that is unique from all others, because of different numbers of protons.
Symbol ~ unique letter to represent element
Element ~ matter that is unique from all others, because of different numbers of protons. Symbol ~ unique letter to represent element
Atomic Number ~ number of protons in the atom of an element
Element ~ smallest particle that is unique from all others
Symbol ~ unique letter to represent element
Atomic Number ~ number of protons in the atom of an element
Carbon - 12 (6 protons, 6 neutrons)
Carbon - 14 (6 protons, 8 neutrons)
Element ~ matter that is unique from all others, because of different numbers of protons.
Symbol ~ unique letter to represent element
Atomic Number ~ number of protons in the atom of an element
Atomic Mass ~ number of neutrons AND number of protons
Isotope ~ atoms of the same element, with different numbers of neutrons
Element ~ smallest particle that is unique from all others
Symbol ~ unique letter to represent element
Atomic Number ~ number of protons in the atom of an element
Atomic Mass ~ number of neutrons AND number of protons
Isotope ~ atoms of the same element, with different numbers of neutrons
Carbon - 12 (6 protons, 6 neutrons)
Carbon - 14 (6 protons, 8 neutrons)
SAME ELEMENT, DIFFERENT NEUTRON NUMBERS
Element ~ matter that is unique from all others, because of different numbers of protons.
Symbol ~ unique letter to represent element
Atomic Number ~ number of protons in the atom of an element
Atomic Mass ~ number of neutrons AND number of protons
Isotope ~ atoms of the same element, with different numbers of neutrons
Atomic Mass Unit ~ 1/12th of the mass of one carbon-12 atom
Element ~ matter that is unique from all others, because of different numbers of protons.
Symbol ~ unique letter to represent element
Atomic Number ~ number of protons in the atom of an element
Atomic Mass ~ number of neutrons AND number of protons
Isotope ~ atoms of the same element, with different numbers of neutrons
Atomic Mass Unit ~ 1/12th of the mass of one carbon-12 atom
The periodic table shows the atomic mass of Nickel as 58.693. How can there be a decimal point, if the mass is whole numbers of protons and neutrons?
Element ~ smallest particle that is unique from all others
Symbol ~ unique letter to represent element
Atomic Number ~ number of protons in the atom of an element
Atomic Mass ~ number of neutrons AND number of protons
Isotope ~ atoms of the same element, with different numbers of neutrons
Atomic Mass Unit ~ 1/12th of the mass of one carbon-12 atom
The periodic table shows the atomic mass of Nickel as 58.693. How can there be a decimal point, if the mass is whole numbers of protons and neutrons?
Example, with boron.
Facts: Boron has an accepted amu of 10.811
80% of Boron in nature have 5 protons, 6 neutrons ~ 11 amu
20% of Boron in nature have 5 protons, 5 neutrons ~ 10 amu
(.8 • 11 amu) + (.2 • 10 amu) = 8.8 amu + 2 amu = 10.8 amu
There are a few extra isotopes out there that we did not include.
Nickel, in nature, has 8 (pretty) stable isotopes. Each has (of course) 28 protons.
Percent NumberNumber Atomic inof of mass Isotope nature
protons neutrons units
Ni-58 69% 28 30 58
Ni-60 27% 28 32 60
Ni-62 4% 28 34 62
What, given this information, is the approximate atomic mass of Nickel?
Nickel, in nature, has 8 (pretty) stable isotopes. Each has (of course) 28 protons.
Percent NumberNumber Atomic inof of mass Isotope nature
protons neutrons units
Ni-58 69% 28 30 58
Ni-60 27% 28 32 60
Ni-62 4% 28 34 62
(.69 • 58) + (.27 • 60) + (.04 • 62) = 58.7 amu
