Download Inside the Atom Note Sheet

Inside the Atom
Objectives:
• Use the periodic table to determine the number of protons, neutrons, and electrons
in an atom or ion
• Determine the identity of an atom or ion using the number of subatomic particles
and the periodic table
Robert Millikan (experimentation 1909-1911)
Oil Drop Experiment-
Purpose: to determine the charge of an
electron in coulombs
Various numbers of electrons were added to
drops of oil. The total charge on each drop
was determined to be a multiple of the same
charge—this charge was assumed to be the
charge of 1 electron. The charge to mass ratio was known therefore the
charge was used to solve the equation for the mass of the electron.
Conclusion-
The mass of 1 electron is 1/1840 the mass of a proton—essentially the
electron has no mass
The Neutron
Atoms of neon were found to have different masses.
• there must be a third particle--one with mass but no charge
• James Chadwick proved the existence of the neutron in 1932
Summary and Atomic Structure
Particle
Electric Charge
Actual Mass (g) Relative Mass (amu)
Electron
-1
9.11x10-28
g
0
Proton
+1
1.67x10-24
g
1
Neutron
0
1.67x10-24
g
1
Location in atom
Outside the
nucleus
nucleus
nucleus
How can I use a model to represent subatomic
particle information from the Periodic Table?
T. O’Toole
Protons, Electrons and Neutrons
define atomic number (Z)- number of protons in an atom or ion
Cobalt has 27 protons in the nucleus
Cobalt has 27
electrons surrounding the nucleus in a neutral atom
define ion- a charged particle that is created by gaining or losing electrons
define anion- a negatively charged particle created by gaining electrons
(more electrons than protons)
define cation- a positively charged particle created by losing electrons (less
electrons than protons)
How many electrons are in a Na+1 cation??
sodium has 11 protons and electrons
How many electrons are in a P-3 anion??
phosphorus has 15 protons and electrons
cation means it loses electrons
anion means it gains electrons
+1 means it loses 1 electron
-3 means it gains 3 electrons
there are 10 electrons in Na+1
there are 18 electrons in P-3
define atomic mass number (A)- the SUM of protons + neutrons
Cobalt has 32 neutrons in the nucleus
How can I use a model to represent subatomic
particle information from the Periodic Table?
T. O’Toole
Minute Paper (also on Portfolio Page)
How do I get from where I am to where I’m going?
The 10 Minute Makeover
Customize your learning by choosing from the following options each night
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Complete the appropriate section on the Portfolio Page
Complete SYS Assignment related book work
Review the PPT file on the website
Read pages 113-121 in the book
Practice using: http://www.quia.com/jg/1211136list.html, OR
http://science.widener.edu/svb/tutorial/protonscsn7.html,
OR(http://www.sciencegeek.net/Chemistry/taters/Unit1Numbers2.htm)
Check out the tutorial resources in the LiveBinder
Review the skills from today’s Train Your Brain
How can I use a model to represent subatomic
particle information from the Periodic Table?
T. O’Toole