Monday, September 12

Wednesday, September 14

Friday, September 16

Monday, September 19

Wednesday, September 21

Friday, September 23

Monday, September 26

Wednesday, September 28

Friday, September 30

Monday, September 12

Intro to Chemistry 201! We looked over the Course Information Sheet. You can print this off when you logon to the Desire2Learn site: click here to logon.

Wednesday, September 14

We clarified info from the Course Information Sheet and just started a little information about the nature of light. I will recap for Friday's class and include more in Friday's entry!

Friday, September 16

To understand Atomic Structure, we started by understanding the the nature of light:

We discussed Light as a wave, and its properties, along with the classification of electromagnetic radiation.

SKILL: convert between wavelength, frequency

We talked about Max Planck and his revolutionary idea.

Key words: continuous vs. quantized

SKILL: determine the energy of a photon

Dual Nature of Light: behaves as both a wave and a particle and exhibits properties of both

de Broglie's equation is important as matter also has wave properties - we will return to this idea for electrons in an atom

SKILL: determine the wavelength of matter

Monday, September 19

X-Ray Diffraction uses the wave properties of light (X-rays) to "look" at the positions of atoms in molecules or ions when crystallised.

We looked Atomic Spectrum of Hydrogen.

Key words: (Fig 7.6) continuous spectrum vs. line spectrum: emission and absorption

The full emission spectrum of hydrogen includes lines outside of the visible range.

REMEMBER: The light observed is emitted as the electron in the H atom undergoes a transition from a higher energy level to a lower one.

For the sections covered so far - Exercises from Chang: 7.8, 7.12, 7.18, 7.25, 7.40

We will see some more examples of emission in Demo 1 and in Experiment 2.

We started talking about some of the implications of 7.3 Bohr's Theory of the Hydrogen Atom

More on this next day!

Wednesday, September 21

We continued discussing 7.3.

Definition: The lowest energy state is called the

SKILL: determine energy levels, or transitions between levels

Convention: n=infinity is zero, so energy levels are negative

Exercise: 32

Better theory uses 7.4 The Dual Nature of the Electron: The important thing here is to remember that electrons have wave properties. In the atom, the electron is bound to the nucleus as a standing wave. This is used in the mathematical treatment of wave mechanics. 7.5 Quantum Mechanics

The take home message of this model - since we will not worry about the math in this course - we have energy levels in this model as well.

The energy levels are calculated and generate 3D functions - more on this next class.

Where is the electron in an orbital? Unanswerable question, Heisenberg uncertainty principle

Friday, September 23

So, how do we describe the electron in the H atom?

By its energy and by a Statistical description: we can't know for sure where it is, but we can say where it is likely to be - probability.

When an electron is in a specific orbital, we know 2 important things:

1. where the electron is likely to be

2. what energy the electron has

To label atomic orbitals, we covered 7.6 Quantum Numbers. There are rules associated with these numbers. The set of quantum numbers tells us about the size, shape and orientation of an orbital.

We had DEMO 1!!!! Info about Demonstration #1 can also be found in D2L

Emission (Atomic Spectra)

Remember, an atom in an excited state can emit light of specific wavelength when falling back to the ground state

1. Discharge tubes containing selected noble gases:

2. Flame tests: in expt 2, you’ll do your own examples

For both of these parts, if we passed the light through a prism, we would see a line spectrum!

We introduced the rules for quantum numbers. Exercises: 56, 60, 66

SKILL: given a set of quantum numbers, determine if the numbers are valid, and if so, label the orbitals

SKILL: given a shell or subshell, determine the quantum numbers for all the orbitals (or give the number of orbitals)

SKILL: given an orbital designation, determine the quantum numbers

REMEMBER: All orbital shapes for H atom come from mathematical functions

We started to look at the way chemists visualise 7.7 Atomic Orbitals (or AOs)

Convention: relative orbital size based on 90% of the total electron probability

Wednesday, September 28

Some quantum number homework: answer.

We continued discussing 7.7 Atomic Orbitals, for s orbitals and looked at the energy levels in the H atom.

Definition: all energies are the same for

REMEMBER: All orbital shapes for H atom come from mathematical functions

We looked more carefully at the 1s, 2s, and 3s orbitals. The overlapping radial probability diagram showed the nodes of the 2s, and 3s orbitals.

Friday, September 30

We drew p orbitals and talked about their shapes and energies.

Then we drew d orbitals and talked about their shapes and energies.

Demo 2 - a preview of the next chapter!