chapter 3
DESCRIPTION
Chapter 3. Atoms. Ions. Ions. If an ion has a charge of -2, what has happened to the atom?. The atom has gained two electrons. If an ion has a charge of +2, what has happened to the atom?. The atom has lost two electrons. Isotopes. Isotopes. Count the neutrons and protons. Proton. - PowerPoint PPT PresentationTRANSCRIPT
Chapter 3
Atoms
Ions
If an ion has a charge of -2, what has happened to the atom?
Ions
If an ion has a charge of +2, what has happened to the atom?
The atom has gained two electrons
The atom has lost two electrons
Isotopes
http://www.green-planet-solar-energy.com/images/helium-isotopes-5-to-8.gif
Isotopes
Count the neutrons and protons
Proton
Neutron
TimelineBeg
inni
ng
Pres
ent
Boyl
e
Gre
eks
Dal
ton
Bohr
Cur
ie
Rut
herf
ord
Mill
ikan
Thom
son
Periodic Table
Atomic Number
Mass Number
Name
Symbol
Element Symbol
Symbol
Atomic Number
Mass Number
Vocabulary
•Electron•Proton•Neutron•Nucleus•Ion•Isotope
•Atom•Compound•Atomic
Number•Mass Number
1 copper atom = 1.0552 x 10-25 kg on average
69.2% of Cu atoms are 1.04497 x 10-25 kg
30.8% of Cu atoms are 1.07815 x 10-25 kg
1 copper penny = 3.1276 x 10-3 kg
3.1276 x 10-3 kg 1 Cu atom = 2.9640 x 1022 atoms
1.0552 x 10-25 kg
Relative Size
Average Atomic Mass Calcs
1 atomic mass unit (amu) = 1.66054x10-27
kg, Mass of an electron = 9.10939x10-31 kgMass of a proton = 1.67262x10-27 kg Mass of a neutron = 1.67493x10-27 kg
Carbon has 2 common isotopes. 126C and 13
6C. If the abundance of the two isotopes is 98.89% and 1.11 % respectively, what is the average atomic mass of carbon in amu?
6 protons1.67262x10-27
kg 1 amu=6.04364 amu
1 proton1.66054x10-27
kg
6 neutrons
1.67493x10-27
kg 1 amu=6.05200 amu
1 neutron1.66054x10-27
kg
6 electrons
9.10939x10-31
kg 1 amu=
0.0032915 amu
1 electron1.66054x10-27
kg
6.04364 amu + 6.05200 amu + 0.0032915 amu =12.09893 amu
126C
6 protons1.67262x10-27
kg 1 amu=6.04364 amu
1 proton1.66054x10-27
kg
7 neutrons
1.67493x10-27
kg 1 amu=7.06066 amu
1 neutron1.66054x10-27
kg
6 electrons
9.10939x10-31
kg 1 amu=
0.0032915 amu
1 electron1.66054x10-27
kg
6.04364 amu + 7.06066 amu + 0.0032915 amu = 13.10755 amu
136C
Putting It All Together
Carbon – 12: 12.09893 amu (98.89% abundance)
Carbon – 13: 13.10755 amu (1.11% abundance)
(12.09893 amu x 0.9889) + (13.10755 amu x 0.0111)
12.01101 amu