2010 Ch 7 lecture notes_part1-1

2010 Ch 7 lecture notes_part1-1 -...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: bc890c36ef4be6be3b3630dc723e95eda741a29c.doc Ch. 7: The Quantum Mechanical Model of the Atom In this chapter well start talking about electrons in atoms. In order to understand how these facts were discovered, we need to first learn some basics about light. Quantum Mechanics: A theory that explains the behavior of very small things We try to understand things, by observing them, and classical physics is based on this. We can observe the trajectory of a ball traveling in the air. Light helps us view this phenomenon, but it has no impact on the balls motion. It is very difficult to observe smaller objects, like electrons. If we use light to try to observe an electron, the electron can actually gain energy from the light and we change the behavior we are trying to observe. There are limits of what we can observe about electrons and what we can know about electrons. Microscopic objects behave differently than what we are used to seeing with macroscopic objects. An understanding of electrons and their positions in atoms will help us understand ions, and why they form as they do. 7.2 Atoms, Electrons and The Nature of Light (a) The Wave Nature of Light Properties of Waves (Classical Physics description of light) Light: a form of electromagnetic radiation (has an electric field component and a magnetic field component). There are various forms of light: visible light (we can see) but others we cant see (UV, IR, microwaves, etc.) Waves: vibrating disturbances by which energy is transmitted Page 1 of 23 bc890c36ef4be6be3b3630dc723e95eda741a29c.doc The speed of waves: depends on medium traveling through & nature of specific light itself. Waves are periodic in nature (repeat themselves) All waves can be characterized by: (1) wavelength: distance between identical parts of a wave on successive waves All pictures from: Ebbing, Gammon: General Chemistry; 8 th edition Wavelength usually symbolized by Greek letter lambda: The most common units of wavelength are nanometers (nm) = one billionth of a meter, or 10 9 nm = 1 m. Other units can be m, cm (2) frequency: number of cycles of a wave per a given unit of time (usually cycles per second or # of waves per second) Frequency usually symbolized by the Greek letter nu: The most common units of frequency are Hertz: Page 2 of 23 bc890c36ef4be6be3b3630dc723e95eda741a29c.doc 1 Hz = 1 cycle per second , or 1 wave per second 1 / s or s-1 = Hz (3) speed: (of a wave) = its wavelength...
View Full Document

Page1 / 23

2010 Ch 7 lecture notes_part1-1 -...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online