1. ATOMIC STRUCTURE

2. Dalton’s Atomic Theory Objective: Identify the main features of Dalton’s Atomic Theory
Each element is made up of tiny, individual particles called atoms.
Atoms are indivisible; they cannot be created or destroyed.
All atoms of a given element are identical.
Atoms of one element are different from those of any other element.
Atoms of two different elements have different masses.
Atoms of different elements may combine in the ratio of small, whole numbers to form compounds.
Chemical reactions occur when atoms are separated, joined, or rearranged.

3. Subatomic Particles Objective: Identify the three major subatomic particles by charge, relative mass and location in the atom.
Subatomic Particle
Symbol
Charge
Mass
(grams)
Relative Mass
(amu)
Location
Discovered
Electron e- 1-
9.109 x 10-28
Outside
Nucleus
1897 by
Thompson
Proton p+ 1+
1.673 x 10-24 1
Inside
1919 by
Rutherford
Neutron n°
1.675 x 10-24
1932 by
Chadwick

4. J.J. Thompson’s Experiments Objective: Describe and/or interpret the Thompson cathode ray experiments.

5. Millikan’s Oil Drop Experiment
Mass and Charge of the electron
Knowing the electron’s charge ( x coulombs) and using the known charge-to-mass ratio, calculate mass of electron.

6. Ernest Rutherford’s Experiments Objective: Describe and/or interpret the Rutherford scattering experiments and the nuclear model of the atom.

8. The Nuclear Model of the Atom
Every atom contains an extremely small, extremely dense nucleus.
All of the positive charge and nearly all of the mass of the atom are concentrated in the nucleus.
The nucleus is surrounded by a much larger volume of nearly empty space that makes up the rest of the atom.
The space outside the nucleus is very thinly, randomly populated by electrons, the total charge of which exactly balances the positive charge of the nucleus.

9. Distinguishing Between Atoms Objectives: - Explain how the atomic number identifies an element - Explain what isotopes of an element are and how they differ. - Explain what an ion is and what information it gives about an element. - Using Isotope Notation, given one of the following, state the others: (a) nuclear symbol; (b) number of protons, neutrons, and electrons; (c) atomic number, mass number and charge.
Isotope Notation (Nuclear Symbol) Sy
mass # (protons + neutrons) A
charge
difference between protons and electrons
atomic # (protons) Z

10. Barium 54 Oxygen 10 82 206 Zinc-66 Name of Element Elemental Symbol
Atomic
Number Z
Numberof Protons
Number of Neutrons
Mass A
Number of Electrons
Nuclear
Symbol
Isotope
Name
Barium 54
Oxygen 10 82
206
Zinc-66